Merge branch 'master' into eclipsecomplains

2024-12-14 11:03:09 +02:00 · 2019-11-06 13:07:50 +01:00 · 2019-11-06 13:07:50 +01:00 · d50b0512a9
commit d50b0512a9
parent 651683758d ee57a1e79d
27 changed files with 1483 additions and 94 deletions
--- a/.gitignore
+++ b/.gitignore
@ -8,6 +8,7 @@ reports
 .classpath
 .project
 *~
+.vscode

 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
@ -19,5 +20,5 @@ documentation/docs-gen
 consumer-test/**/workspace

 *.code-workspace
-piper
-piper.exe
+/piper
+/piper.exe
--- a/cmd/getConfig.go
+++ b/cmd/getConfig.go
@ -86,8 +86,6 @@ func generateConfig() error {
 		return errors.Wrap(err, "getting step config failed")
 	}

-	//ToDo: Check for mandatory parameters
-
 	myConfigJSON, _ := config.GetJSON(stepConfig.Config)

 	fmt.Println(myConfigJSON)
--- a/cmd/githubPublishRelease.go
+++ b/cmd/githubPublishRelease.go
@ -0,0 +1,217 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"mime"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/SAP/jenkins-library/pkg/log"
+	"github.com/google/go-github/v28/github"
+	"github.com/pkg/errors"
+
+	piperGithub "github.com/SAP/jenkins-library/pkg/github"
+)
+
+type githubRepoClient interface {
+	CreateRelease(ctx context.Context, owner string, repo string, release *github.RepositoryRelease) (*github.RepositoryRelease, *github.Response, error)
+	DeleteReleaseAsset(ctx context.Context, owner string, repo string, id int64) (*github.Response, error)
+	GetLatestRelease(ctx context.Context, owner string, repo string) (*github.RepositoryRelease, *github.Response, error)
+	ListReleaseAssets(ctx context.Context, owner string, repo string, id int64, opt *github.ListOptions) ([]*github.ReleaseAsset, *github.Response, error)
+	UploadReleaseAsset(ctx context.Context, owner string, repo string, id int64, opt *github.UploadOptions, file *os.File) (*github.ReleaseAsset, *github.Response, error)
+}
+
+type githubIssueClient interface {
+	ListByRepo(ctx context.Context, owner string, repo string, opt *github.IssueListByRepoOptions) ([]*github.Issue, *github.Response, error)
+}
+
+func githubPublishRelease(myGithubPublishReleaseOptions githubPublishReleaseOptions) error {
+	ctx, client, err := piperGithub.NewClient(myGithubPublishReleaseOptions.Token, myGithubPublishReleaseOptions.APIURL, myGithubPublishReleaseOptions.UploadURL)
+	if err != nil {
+		log.Entry().WithError(err).Fatal("Failed to get GitHub client.")
+	}
+
+	err = runGithubPublishRelease(ctx, &myGithubPublishReleaseOptions, client.Repositories, client.Issues)
+	if err != nil {
+		log.Entry().WithError(err).Fatal("Failed to publish GitHub release.")
+	}
+
+	return nil
+}
+
+func runGithubPublishRelease(ctx context.Context, myGithubPublishReleaseOptions *githubPublishReleaseOptions, ghRepoClient githubRepoClient, ghIssueClient githubIssueClient) error {
+
+	var publishedAt github.Timestamp
+
+	lastRelease, resp, err := ghRepoClient.GetLatestRelease(ctx, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository)
+	if err != nil {
+		if resp.StatusCode == 404 {
+			//no previous release found -> first release
+			myGithubPublishReleaseOptions.AddDeltaToLastRelease = false
+			log.Entry().Debug("This is the first release.")
+		} else {
+			return errors.Wrap(err, "Error occured when retrieving latest GitHub release.")
+		}
+	}
+	publishedAt = lastRelease.GetPublishedAt()
+	log.Entry().Debugf("Previous GitHub release published: '%v'", publishedAt)
+
+	//updating assets only supported on latest release
+	if myGithubPublishReleaseOptions.UpdateAsset && myGithubPublishReleaseOptions.Version == "latest" {
+		return uploadReleaseAsset(ctx, lastRelease.GetID(), myGithubPublishReleaseOptions, ghRepoClient)
+	}
+
+	releaseBody := ""
+
+	if len(myGithubPublishReleaseOptions.ReleaseBodyHeader) > 0 {
+		releaseBody += myGithubPublishReleaseOptions.ReleaseBodyHeader + "\n"
+	}
+
+	if myGithubPublishReleaseOptions.AddClosedIssues {
+		releaseBody += getClosedIssuesText(ctx, publishedAt, myGithubPublishReleaseOptions, ghIssueClient)
+	}
+
+	if myGithubPublishReleaseOptions.AddDeltaToLastRelease {
+		releaseBody += getReleaseDeltaText(myGithubPublishReleaseOptions, lastRelease)
+	}
+
+	release := github.RepositoryRelease{
+		TagName:         &myGithubPublishReleaseOptions.Version,
+		TargetCommitish: &myGithubPublishReleaseOptions.Commitish,
+		Name:            &myGithubPublishReleaseOptions.Version,
+		Body:            &releaseBody,
+	}
+
+	createdRelease, _, err := ghRepoClient.CreateRelease(ctx, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository, &release)
+	if err != nil {
+		return errors.Wrapf(err, "Creation of release '%v' failed", *release.TagName)
+	}
+	log.Entry().Infof("Release %v created on %v/%v", *createdRelease.TagName, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository)
+
+	if len(myGithubPublishReleaseOptions.AssetPath) > 0 {
+		return uploadReleaseAsset(ctx, createdRelease.GetID(), myGithubPublishReleaseOptions, ghRepoClient)
+	}
+
+	return nil
+}
+
+func getClosedIssuesText(ctx context.Context, publishedAt github.Timestamp, myGithubPublishReleaseOptions *githubPublishReleaseOptions, ghIssueClient githubIssueClient) string {
+	closedIssuesText := ""
+
+	options := github.IssueListByRepoOptions{
+		State:     "closed",
+		Direction: "asc",
+		Since:     publishedAt.Time,
+	}
+	if len(myGithubPublishReleaseOptions.Labels) > 0 {
+		options.Labels = myGithubPublishReleaseOptions.Labels
+	}
+	ghIssues, _, err := ghIssueClient.ListByRepo(ctx, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository, &options)
+	if err != nil {
+		log.Entry().WithError(err).Error("Failed to get GitHub issues.")
+	}
+
+	prTexts := []string{"**List of closed pull-requests since last release**"}
+	issueTexts := []string{"**List of closed issues since last release**"}
+
+	for _, issue := range ghIssues {
+		if issue.IsPullRequest() && !isExcluded(issue, myGithubPublishReleaseOptions.ExcludeLabels) {
+			prTexts = append(prTexts, fmt.Sprintf("[#%v](%v): %v", issue.GetNumber(), issue.GetHTMLURL(), issue.GetTitle()))
+			log.Entry().Debugf("Added PR #%v to release", issue.GetNumber())
+		} else if !issue.IsPullRequest() && !isExcluded(issue, myGithubPublishReleaseOptions.ExcludeLabels) {
+			issueTexts = append(issueTexts, fmt.Sprintf("[#%v](%v): %v", issue.GetNumber(), issue.GetHTMLURL(), issue.GetTitle()))
+			log.Entry().Debugf("Added Issue #%v to release", issue.GetNumber())
+		}
+	}
+
+	if len(prTexts) > 1 {
+		closedIssuesText += "\n" + strings.Join(prTexts, "\n") + "\n"
+	}
+
+	if len(issueTexts) > 1 {
+		closedIssuesText += "\n" + strings.Join(issueTexts, "\n") + "\n"
+	}
+	return closedIssuesText
+}
+
+func getReleaseDeltaText(myGithubPublishReleaseOptions *githubPublishReleaseOptions, lastRelease *github.RepositoryRelease) string {
+	releaseDeltaText := ""
+
+	//add delta link to previous release
+	releaseDeltaText += "\n**Changes**\n"
+	releaseDeltaText += fmt.Sprintf(
+		"[%v...%v](%v/%v/%v/compare/%v...%v)\n",
+		lastRelease.GetTagName(),
+		myGithubPublishReleaseOptions.Version,
+		myGithubPublishReleaseOptions.ServerURL,
+		myGithubPublishReleaseOptions.Owner,
+		myGithubPublishReleaseOptions.Repository,
+		lastRelease.GetTagName(), myGithubPublishReleaseOptions.Version,
+	)
+
+	return releaseDeltaText
+}
+
+func uploadReleaseAsset(ctx context.Context, releaseID int64, myGithubPublishReleaseOptions *githubPublishReleaseOptions, ghRepoClient githubRepoClient) error {
+
+	assets, _, err := ghRepoClient.ListReleaseAssets(ctx, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository, releaseID, &github.ListOptions{})
+	if err != nil {
+		return errors.Wrap(err, "Failed to get list of release assets.")
+	}
+	var assetID int64
+	for _, a := range assets {
+		if a.GetName() == filepath.Base(myGithubPublishReleaseOptions.AssetPath) {
+			assetID = a.GetID()
+			break
+		}
+	}
+	if assetID != 0 {
+		//asset needs to be deleted first since API does not allow for replacement
+		_, err := ghRepoClient.DeleteReleaseAsset(ctx, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository, assetID)
+		if err != nil {
+			return errors.Wrap(err, "Failed to delete release asset.")
+		}
+	}
+
+	mediaType := mime.TypeByExtension(filepath.Ext(myGithubPublishReleaseOptions.AssetPath))
+	if mediaType == "" {
+		mediaType = "application/octet-stream"
+	}
+	log.Entry().Debugf("Using mediaType '%v'", mediaType)
+
+	name := filepath.Base(myGithubPublishReleaseOptions.AssetPath)
+	log.Entry().Debugf("Using file name '%v'", name)
+
+	opts := github.UploadOptions{
+		Name:      name,
+		MediaType: mediaType,
+	}
+	file, err := os.Open(myGithubPublishReleaseOptions.AssetPath)
+	defer file.Close()
+	if err != nil {
+		return errors.Wrapf(err, "Failed to load release asset '%v'", myGithubPublishReleaseOptions.AssetPath)
+	}
+
+	log.Entry().Info("Starting to upload release asset.")
+	asset, _, err := ghRepoClient.UploadReleaseAsset(ctx, myGithubPublishReleaseOptions.Owner, myGithubPublishReleaseOptions.Repository, releaseID, &opts, file)
+	if err != nil {
+		return errors.Wrap(err, "Failed to upload release asset.")
+	}
+	log.Entry().Infof("Done uploading asset '%v'.", asset.GetURL())
+
+	return nil
+}
+
+func isExcluded(issue *github.Issue, excludeLabels []string) bool {
+	//issue.Labels[0].GetName()
+	for _, ex := range excludeLabels {
+		for _, l := range issue.Labels {
+			if ex == l.GetName() {
+				return true
+			}
+		}
+	}
+	return false
+}
--- a/cmd/githubPublishRelease_generated.go
+++ b/cmd/githubPublishRelease_generated.go
@ -0,0 +1,189 @@
+package cmd
+
+import (
+	"os"
+
+	"github.com/SAP/jenkins-library/pkg/config"
+	"github.com/SAP/jenkins-library/pkg/log"
+	"github.com/spf13/cobra"
+)
+
+type githubPublishReleaseOptions struct {
+	AddClosedIssues       bool     `json:"addClosedIssues,omitempty"`
+	AddDeltaToLastRelease bool     `json:"addDeltaToLastRelease,omitempty"`
+	AssetPath             string   `json:"assetPath,omitempty"`
+	Commitish             string   `json:"commitish,omitempty"`
+	ExcludeLabels         []string `json:"excludeLabels,omitempty"`
+	APIURL                string   `json:"apiUrl,omitempty"`
+	Owner                 string   `json:"owner,omitempty"`
+	Repository            string   `json:"repository,omitempty"`
+	ServerURL             string   `json:"serverUrl,omitempty"`
+	Token                 string   `json:"token,omitempty"`
+	UploadURL             string   `json:"uploadUrl,omitempty"`
+	Labels                []string `json:"labels,omitempty"`
+	ReleaseBodyHeader     string   `json:"releaseBodyHeader,omitempty"`
+	UpdateAsset           bool     `json:"updateAsset,omitempty"`
+	Version               string   `json:"version,omitempty"`
+}
+
+var myGithubPublishReleaseOptions githubPublishReleaseOptions
+var githubPublishReleaseStepConfigJSON string
+
+// GithubPublishReleaseCommand Publish a release in GitHub
+func GithubPublishReleaseCommand() *cobra.Command {
+	metadata := githubPublishReleaseMetadata()
+	var createGithubPublishReleaseCmd = &cobra.Command{
+		Use:   "githubPublishRelease",
+		Short: "Publish a release in GitHub",
+		Long: `This step creates a tag in your GitHub repository together with a release.
+The release can be filled with text plus additional information like:
+
+* Closed pull request since last release
+* Closed issues since last release
+* Link to delta information showing all commits since last release
+
+The result looks like
+
+![Example release](../images/githubRelease.png)`,
+		PreRunE: func(cmd *cobra.Command, args []string) error {
+			log.SetStepName("githubPublishRelease")
+			log.SetVerbose(generalConfig.verbose)
+			return PrepareConfig(cmd, &metadata, "githubPublishRelease", &myGithubPublishReleaseOptions, openPiperFile)
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return githubPublishRelease(myGithubPublishReleaseOptions)
+		},
+	}
+
+	addGithubPublishReleaseFlags(createGithubPublishReleaseCmd)
+	return createGithubPublishReleaseCmd
+}
+
+func addGithubPublishReleaseFlags(cmd *cobra.Command) {
+	cmd.Flags().BoolVar(&myGithubPublishReleaseOptions.AddClosedIssues, "addClosedIssues", false, "If set to `true`, closed issues and merged pull-requests since the last release will added below the `releaseBodyHeader`")
+	cmd.Flags().BoolVar(&myGithubPublishReleaseOptions.AddDeltaToLastRelease, "addDeltaToLastRelease", false, "If set to `true`, a link will be added to the relese information that brings up all commits since the last release.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.AssetPath, "assetPath", os.Getenv("PIPER_assetPath"), "Path to a release asset which should be uploaded to the list of release assets.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.Commitish, "commitish", "master", "Target git commitish for the release")
+	cmd.Flags().StringSliceVar(&myGithubPublishReleaseOptions.ExcludeLabels, "excludeLabels", []string{}, "Allows to exclude issues with dedicated list of labels.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.APIURL, "apiUrl", "https://api.github.com", "Set the GitHub API url.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.Owner, "owner", os.Getenv("PIPER_owner"), "Set the GitHub organization.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.Repository, "repository", os.Getenv("PIPER_repository"), "Set the GitHub repository.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.ServerURL, "serverUrl", "https://github.com", "GitHub server url for end-user access.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.Token, "token", os.Getenv("PIPER_token"), "GitHub personal access token as per https://help.github.com/en/github/authenticating-to-github/creating-a-personal-access-token-for-the-command-line")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.UploadURL, "uploadUrl", "https://uploads.github.com", "Set the GitHub API url.")
+	cmd.Flags().StringSliceVar(&myGithubPublishReleaseOptions.Labels, "labels", []string{}, "Labels to include in issue search.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.ReleaseBodyHeader, "releaseBodyHeader", os.Getenv("PIPER_releaseBodyHeader"), "Content which will appear for the release.")
+	cmd.Flags().BoolVar(&myGithubPublishReleaseOptions.UpdateAsset, "updateAsset", false, "Specify if a release asset should be updated only.")
+	cmd.Flags().StringVar(&myGithubPublishReleaseOptions.Version, "version", os.Getenv("PIPER_version"), "Define the version number which will be written as tag as well as release name.")
+
+	cmd.MarkFlagRequired("apiUrl")
+	cmd.MarkFlagRequired("owner")
+	cmd.MarkFlagRequired("repository")
+	cmd.MarkFlagRequired("serverUrl")
+	cmd.MarkFlagRequired("token")
+	cmd.MarkFlagRequired("uploadUrl")
+	cmd.MarkFlagRequired("version")
+}
+
+// retrieve step metadata
+func githubPublishReleaseMetadata() config.StepData {
+	var theMetaData = config.StepData{
+		Spec: config.StepSpec{
+			Inputs: config.StepInputs{
+				Parameters: []config.StepParameters{
+					{
+						Name:      "addClosedIssues",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "bool",
+						Mandatory: false,
+					},
+					{
+						Name:      "addDeltaToLastRelease",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "bool",
+						Mandatory: false,
+					},
+					{
+						Name:      "assetPath",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: false,
+					},
+					{
+						Name:      "commitish",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: false,
+					},
+					{
+						Name:      "excludeLabels",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "[]string",
+						Mandatory: false,
+					},
+					{
+						Name:      "apiUrl",
+						Scope:     []string{"GENERAL", "PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+					{
+						Name:      "owner",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+					{
+						Name:      "repository",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+					{
+						Name:      "serverUrl",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+					{
+						Name:      "token",
+						Scope:     []string{"GENERAL", "PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+					{
+						Name:      "uploadUrl",
+						Scope:     []string{"GENERAL", "PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+					{
+						Name:      "labels",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "[]string",
+						Mandatory: false,
+					},
+					{
+						Name:      "releaseBodyHeader",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: false,
+					},
+					{
+						Name:      "updateAsset",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "bool",
+						Mandatory: false,
+					},
+					{
+						Name:      "version",
+						Scope:     []string{"PARAMETERS", "STAGES", "STEPS"},
+						Type:      "string",
+						Mandatory: true,
+					},
+				},
+			},
+		},
+	}
+	return theMetaData
+}
--- a/cmd/githubPublishRelease_generated_test.go
+++ b/cmd/githubPublishRelease_generated_test.go
@ -0,0 +1,16 @@
+package cmd
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGithubPublishReleaseCommand(t *testing.T) {
+
+	testCmd := GithubPublishReleaseCommand()
+
+	// only high level testing performed - details are tested in step generation procudure
+	assert.Equal(t, "githubPublishRelease", testCmd.Use, "command name incorrect")
+
+}
--- a/cmd/githubPublishRelease_test.go
+++ b/cmd/githubPublishRelease_test.go
@ -0,0 +1,383 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/google/go-github/v28/github"
+	"github.com/stretchr/testify/assert"
+)
+
+type ghRCMock struct {
+	createErr         error
+	latestRelease     *github.RepositoryRelease
+	release           *github.RepositoryRelease
+	delErr            error
+	delID             int64
+	delOwner          string
+	delRepo           string
+	listErr           error
+	listID            int64
+	listOwner         string
+	listReleaseAssets []*github.ReleaseAsset
+	listRepo          string
+	listOpts          *github.ListOptions
+	latestStatusCode  int
+	latestErr         error
+	uploadID          int64
+	uploadOpts        *github.UploadOptions
+	uploadOwner       string
+	uploadRepo        string
+}
+
+func (g *ghRCMock) CreateRelease(ctx context.Context, owner string, repo string, release *github.RepositoryRelease) (*github.RepositoryRelease, *github.Response, error) {
+	g.release = release
+	return release, nil, g.createErr
+}
+
+func (g *ghRCMock) DeleteReleaseAsset(ctx context.Context, owner string, repo string, id int64) (*github.Response, error) {
+	g.delOwner = owner
+	g.delRepo = repo
+	g.delID = id
+	return nil, g.delErr
+}
+
+func (g *ghRCMock) GetLatestRelease(ctx context.Context, owner string, repo string) (*github.RepositoryRelease, *github.Response, error) {
+	hc := http.Response{StatusCode: 200}
+	if g.latestStatusCode != 0 {
+		hc.StatusCode = g.latestStatusCode
+	}
+	ghResp := github.Response{Response: &hc}
+	return g.latestRelease, &ghResp, g.latestErr
+}
+
+func (g *ghRCMock) ListReleaseAssets(ctx context.Context, owner string, repo string, id int64, opt *github.ListOptions) ([]*github.ReleaseAsset, *github.Response, error) {
+	g.listID = id
+	g.listOwner = owner
+	g.listRepo = repo
+	g.listOpts = opt
+	return g.listReleaseAssets, nil, g.listErr
+}
+
+func (g *ghRCMock) UploadReleaseAsset(ctx context.Context, owner string, repo string, id int64, opt *github.UploadOptions, file *os.File) (*github.ReleaseAsset, *github.Response, error) {
+	g.uploadID = id
+	g.uploadOwner = owner
+	g.uploadRepo = repo
+	g.uploadOpts = opt
+	return nil, nil, nil
+}
+
+type ghICMock struct {
+	issues        []*github.Issue
+	lastPublished time.Time
+	owner         string
+	repo          string
+	options       *github.IssueListByRepoOptions
+}
+
+func (g *ghICMock) ListByRepo(ctx context.Context, owner string, repo string, opt *github.IssueListByRepoOptions) ([]*github.Issue, *github.Response, error) {
+	g.owner = owner
+	g.repo = repo
+	g.options = opt
+	g.lastPublished = opt.Since
+	return g.issues, nil, nil
+}
+
+func TestRunGithubPublishRelease(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("Success - first release & no body", func(t *testing.T) {
+		ghIssueClient := ghICMock{}
+		ghRepoClient := ghRCMock{
+			latestStatusCode: 404,
+			latestErr:        fmt.Errorf("not found"),
+		}
+
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			AddDeltaToLastRelease: true,
+			Commitish:             "master",
+			Owner:                 "TEST",
+			Repository:            "test",
+			ServerURL:             "https://github.com",
+			ReleaseBodyHeader:     "Header",
+			Version:               "1.0",
+		}
+		err := runGithubPublishRelease(ctx, &myGithubPublishReleaseOptions, &ghRepoClient, &ghIssueClient)
+		assert.NoError(t, err, "Error occured but none expected.")
+
+		assert.Equal(t, "Header\n", ghRepoClient.release.GetBody())
+	})
+
+	t.Run("Success - subsequent releases & with body", func(t *testing.T) {
+		lastTag := "1.0"
+		lastPublishedAt := github.Timestamp{Time: time.Date(2019, 01, 01, 0, 0, 0, 0, time.UTC)}
+		ghRepoClient := ghRCMock{
+			createErr: nil,
+			latestRelease: &github.RepositoryRelease{
+				TagName:     &lastTag,
+				PublishedAt: &lastPublishedAt,
+			},
+		}
+		prHTMLURL := "https://github.com/TEST/test/pull/1"
+		prTitle := "Pull"
+		prNo := 1
+
+		issHTMLURL := "https://github.com/TEST/test/issues/2"
+		issTitle := "Issue"
+		issNo := 2
+
+		ghIssueClient := ghICMock{
+			issues: []*github.Issue{
+				{Number: &prNo, Title: &prTitle, HTMLURL: &prHTMLURL, PullRequestLinks: &github.PullRequestLinks{URL: &prHTMLURL}},
+				{Number: &issNo, Title: &issTitle, HTMLURL: &issHTMLURL},
+			},
+		}
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			AddClosedIssues:       true,
+			AddDeltaToLastRelease: true,
+			Commitish:             "master",
+			Owner:                 "TEST",
+			Repository:            "test",
+			ServerURL:             "https://github.com",
+			ReleaseBodyHeader:     "Header",
+			Version:               "1.1",
+		}
+		err := runGithubPublishRelease(ctx, &myGithubPublishReleaseOptions, &ghRepoClient, &ghIssueClient)
+
+		assert.NoError(t, err, "Error occured but none expected.")
+
+		assert.Equal(t, "Header\n\n**List of closed pull-requests since last release**\n[#1](https://github.com/TEST/test/pull/1): Pull\n\n**List of closed issues since last release**\n[#2](https://github.com/TEST/test/issues/2): Issue\n\n**Changes**\n[1.0...1.1](https://github.com/TEST/test/compare/1.0...1.1)\n", ghRepoClient.release.GetBody())
+		assert.Equal(t, "1.1", ghRepoClient.release.GetName())
+		assert.Equal(t, "1.1", ghRepoClient.release.GetTagName())
+		assert.Equal(t, "master", ghRepoClient.release.GetTargetCommitish())
+
+		assert.Equal(t, lastPublishedAt.Time, ghIssueClient.lastPublished)
+	})
+
+	t.Run("Success - update asset", func(t *testing.T) {
+		var releaseID int64 = 1
+		ghIssueClient := ghICMock{}
+		ghRepoClient := ghRCMock{
+			latestRelease: &github.RepositoryRelease{
+				ID: &releaseID,
+			},
+		}
+
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			UpdateAsset: true,
+			AssetPath:   filepath.Join("testdata", t.Name()+"_test.txt"),
+			Version:     "latest",
+		}
+
+		err := runGithubPublishRelease(ctx, &myGithubPublishReleaseOptions, &ghRepoClient, &ghIssueClient)
+
+		assert.NoError(t, err, "Error occured but none expected.")
+
+		assert.Nil(t, ghRepoClient.release)
+
+		assert.Equal(t, releaseID, ghRepoClient.listID)
+		assert.Equal(t, releaseID, ghRepoClient.uploadID)
+	})
+
+	t.Run("Error - get release", func(t *testing.T) {
+		ghIssueClient := ghICMock{}
+		ghRepoClient := ghRCMock{
+			latestErr: fmt.Errorf("Latest release error"),
+		}
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{}
+		err := runGithubPublishRelease(ctx, &myGithubPublishReleaseOptions, &ghRepoClient, &ghIssueClient)
+
+		assert.Equal(t, "Error occured when retrieving latest GitHub release.: Latest release error", fmt.Sprint(err))
+	})
+
+	t.Run("Error - create release", func(t *testing.T) {
+		ghIssueClient := ghICMock{}
+		ghRepoClient := ghRCMock{
+			createErr: fmt.Errorf("Create release error"),
+		}
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			Version: "1.0",
+		}
+		err := runGithubPublishRelease(ctx, &myGithubPublishReleaseOptions, &ghRepoClient, &ghIssueClient)
+
+		assert.Equal(t, "Creation of release '1.0' failed: Create release error", fmt.Sprint(err))
+	})
+}
+
+func TestGetClosedIssuesText(t *testing.T) {
+	ctx := context.Background()
+	publishedAt := github.Timestamp{Time: time.Date(2019, 01, 01, 0, 0, 0, 0, time.UTC)}
+
+	t.Run("No issues", func(t *testing.T) {
+		ghIssueClient := ghICMock{}
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			Version: "1.0",
+		}
+
+		res := getClosedIssuesText(ctx, publishedAt, &myGithubPublishReleaseOptions, &ghIssueClient)
+
+		assert.Equal(t, "", res)
+	})
+
+	t.Run("All issues", func(t *testing.T) {
+		ctx := context.Background()
+		publishedAt := github.Timestamp{Time: time.Date(2019, 01, 01, 0, 0, 0, 0, time.UTC)}
+
+		prHTMLURL := []string{"https://github.com/TEST/test/pull/1", "https://github.com/TEST/test/pull/2"}
+		prTitle := []string{"Pull1", "Pull2"}
+		prNo := []int{1, 2}
+
+		issHTMLURL := []string{"https://github.com/TEST/test/issues/3", "https://github.com/TEST/test/issues/4"}
+		issTitle := []string{"Issue3", "Issue4"}
+		issNo := []int{3, 4}
+
+		ghIssueClient := ghICMock{
+			issues: []*github.Issue{
+				{Number: &prNo[0], Title: &prTitle[0], HTMLURL: &prHTMLURL[0], PullRequestLinks: &github.PullRequestLinks{URL: &prHTMLURL[0]}},
+				{Number: &prNo[1], Title: &prTitle[1], HTMLURL: &prHTMLURL[1], PullRequestLinks: &github.PullRequestLinks{URL: &prHTMLURL[1]}},
+				{Number: &issNo[0], Title: &issTitle[0], HTMLURL: &issHTMLURL[0]},
+				{Number: &issNo[1], Title: &issTitle[1], HTMLURL: &issHTMLURL[1]},
+			},
+		}
+
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			Owner:      "TEST",
+			Repository: "test",
+		}
+
+		res := getClosedIssuesText(ctx, publishedAt, &myGithubPublishReleaseOptions, &ghIssueClient)
+
+		assert.Equal(t, "\n**List of closed pull-requests since last release**\n[#1](https://github.com/TEST/test/pull/1): Pull1\n[#2](https://github.com/TEST/test/pull/2): Pull2\n\n**List of closed issues since last release**\n[#3](https://github.com/TEST/test/issues/3): Issue3\n[#4](https://github.com/TEST/test/issues/4): Issue4\n", res)
+		assert.Equal(t, "TEST", ghIssueClient.owner, "Owner not properly passed")
+		assert.Equal(t, "test", ghIssueClient.repo, "Repo not properly passed")
+		assert.Equal(t, "closed", ghIssueClient.options.State, "Issue state not properly passed")
+		assert.Equal(t, "asc", ghIssueClient.options.Direction, "Sort direction not properly passed")
+		assert.Equal(t, publishedAt.Time, ghIssueClient.options.Since, "PublishedAt not properly passed")
+	})
+
+}
+
+func TestGetReleaseDeltaText(t *testing.T) {
+	myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+		Owner:      "TEST",
+		Repository: "test",
+		ServerURL:  "https://github.com",
+		Version:    "1.1",
+	}
+	lastTag := "1.0"
+	lastRelease := github.RepositoryRelease{
+		TagName: &lastTag,
+	}
+
+	res := getReleaseDeltaText(&myGithubPublishReleaseOptions, &lastRelease)
+
+	assert.Equal(t, "\n**Changes**\n[1.0...1.1](https://github.com/TEST/test/compare/1.0...1.1)\n", res)
+}
+
+func TestUploadReleaseAsset(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("Success - existing asset", func(t *testing.T) {
+		var releaseID int64 = 1
+		assetName := "Success_-_existing_asset_test.txt"
+		var assetID int64 = 11
+		ghRepoClient := ghRCMock{
+			latestRelease: &github.RepositoryRelease{
+				ID: &releaseID,
+			},
+			listReleaseAssets: []*github.ReleaseAsset{
+				{Name: &assetName, ID: &assetID},
+			},
+		}
+
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			Owner:      "TEST",
+			Repository: "test",
+			AssetPath:  filepath.Join("testdata", t.Name()+"_test.txt"),
+		}
+
+		err := uploadReleaseAsset(ctx, releaseID, &myGithubPublishReleaseOptions, &ghRepoClient)
+
+		assert.NoError(t, err, "Error occured but none expected.")
+
+		assert.Equal(t, "TEST", ghRepoClient.listOwner, "Owner not properly passed - list")
+		assert.Equal(t, "test", ghRepoClient.listRepo, "Repo not properly passed - list")
+		assert.Equal(t, releaseID, ghRepoClient.listID, "Relase ID not properly passed - list")
+
+		assert.Equal(t, "TEST", ghRepoClient.delOwner, "Owner not properly passed - del")
+		assert.Equal(t, "test", ghRepoClient.delRepo, "Repo not properly passed - del")
+		assert.Equal(t, assetID, ghRepoClient.delID, "Relase ID not properly passed - del")
+
+		assert.Equal(t, "TEST", ghRepoClient.uploadOwner, "Owner not properly passed - upload")
+		assert.Equal(t, "test", ghRepoClient.uploadRepo, "Repo not properly passed - upload")
+		assert.Equal(t, releaseID, ghRepoClient.uploadID, "Relase ID not properly passed - upload")
+		assert.Equal(t, "text/plain; charset=utf-8", ghRepoClient.uploadOpts.MediaType, "Wrong MediaType passed - upload")
+	})
+
+	t.Run("Success - no asset", func(t *testing.T) {
+		var releaseID int64 = 1
+		assetName := "notFound"
+		var assetID int64 = 11
+		ghRepoClient := ghRCMock{
+			latestRelease: &github.RepositoryRelease{
+				ID: &releaseID,
+			},
+			listReleaseAssets: []*github.ReleaseAsset{
+				{Name: &assetName, ID: &assetID},
+			},
+		}
+
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{
+			Owner:      "TEST",
+			Repository: "test",
+			AssetPath:  filepath.Join("testdata", t.Name()+"_test.txt"),
+		}
+
+		err := uploadReleaseAsset(ctx, releaseID, &myGithubPublishReleaseOptions, &ghRepoClient)
+
+		assert.NoError(t, err, "Error occured but none expected.")
+
+		assert.Equal(t, int64(0), ghRepoClient.delID, "Relase ID should not be populated")
+	})
+
+	t.Run("Error - List Assets", func(t *testing.T) {
+		var releaseID int64 = 1
+		ghRepoClient := ghRCMock{
+			listErr: fmt.Errorf("List Asset Error"),
+		}
+		myGithubPublishReleaseOptions := githubPublishReleaseOptions{}
+
+		err := uploadReleaseAsset(ctx, releaseID, &myGithubPublishReleaseOptions, &ghRepoClient)
+		assert.Equal(t, "Failed to get list of release assets.: List Asset Error", fmt.Sprint(err), "Wrong error received")
+	})
+}
+
+func TestIsExcluded(t *testing.T) {
+
+	l1 := "label1"
+	l2 := "label2"
+
+	tt := []struct {
+		issue         *github.Issue
+		excludeLabels []string
+		expected      bool
+	}{
+		{issue: nil, excludeLabels: nil, expected: false},
+		{issue: &github.Issue{}, excludeLabels: nil, expected: false},
+		{issue: &github.Issue{Labels: []github.Label{{Name: &l1}}}, excludeLabels: nil, expected: false},
+		{issue: &github.Issue{Labels: []github.Label{{Name: &l1}}}, excludeLabels: []string{"label0"}, expected: false},
+		{issue: &github.Issue{Labels: []github.Label{{Name: &l1}}}, excludeLabels: []string{"label1"}, expected: true},
+		{issue: &github.Issue{Labels: []github.Label{{Name: &l1}, {Name: &l2}}}, excludeLabels: []string{}, expected: false},
+		{issue: &github.Issue{Labels: []github.Label{{Name: &l1}, {Name: &l2}}}, excludeLabels: []string{"label1"}, expected: true},
+	}
+
+	for k, v := range tt {
+		assert.Equal(t, v.expected, isExcluded(v.issue, v.excludeLabels), fmt.Sprintf("Run %v failed", k))
+	}
+
+}
--- a/cmd/karmaExecuteTests_generated.go
+++ b/cmd/karmaExecuteTests_generated.go
@ -1,8 +1,6 @@
 package cmd

 import (
-	//"os"
-
 	"github.com/SAP/jenkins-library/pkg/config"
 	"github.com/SAP/jenkins-library/pkg/log"
 	"github.com/spf13/cobra"
--- a/cmd/piper.go
+++ b/cmd/piper.go
@ -41,6 +41,7 @@ func Execute() {
 	rootCmd.AddCommand(ConfigCommand())
 	rootCmd.AddCommand(VersionCommand())
 	rootCmd.AddCommand(KarmaExecuteTestsCommand())
+	rootCmd.AddCommand(GithubPublishReleaseCommand())

 	addRootFlags(rootCmd)
 	if err := rootCmd.Execute(); err != nil {
--- a/cmd/testdata/TestRunGithubPublishRelease/Success_-_update_asset_test.txt
+++ b/cmd/testdata/TestRunGithubPublishRelease/Success_-_update_asset_test.txt
@ -0,0 +1 @@
+TEST
--- a/cmd/testdata/TestUploadReleaseAsset/Success_-_existing_asset_test.txt
+++ b/cmd/testdata/TestUploadReleaseAsset/Success_-_existing_asset_test.txt
@ -0,0 +1 @@
+TEST
--- a/cmd/testdata/TestUploadReleaseAsset/Success_-_no_asset_test.txt
+++ b/cmd/testdata/TestUploadReleaseAsset/Success_-_no_asset_test.txt
@ -0,0 +1 @@
+TEST
--- a/cmd/version_generated.go
+++ b/cmd/version_generated.go
@ -1,8 +1,6 @@
 package cmd

 import (
-	//"os"
-
 	"github.com/SAP/jenkins-library/pkg/config"
 	"github.com/SAP/jenkins-library/pkg/log"
 	"github.com/spf13/cobra"
--- a/go.mod
+++ b/go.mod
@ -4,9 +4,12 @@ go 1.13

 require (
 	github.com/ghodss/yaml v1.0.0
+	github.com/google/go-github/v28 v28.1.1
+	github.com/google/go-cmp v0.3.1
 	github.com/pkg/errors v0.8.1
 	github.com/sirupsen/logrus v1.4.2
 	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.5
 	github.com/stretchr/testify v1.2.2
+	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
 )
--- a/go.sum
+++ b/go.sum
@ -1,3 +1,4 @@
+cloud.google.com/go v0.34.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
@ -9,9 +10,18 @@ github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/google/go-github v17.0.0+incompatible h1:N0LgJ1j65A7kfXrZnUDaYCs/Sf4rEjNlfyDHW9dolSY=
+github.com/google/go-github/v28 v28.1.1 h1:kORf5ekX5qwXO2mGzXXOjMe/g6ap8ahVe0sBEulhSxo=
+github.com/google/go-github/v28 v28.1.1/go.mod h1:bsqJWQX05omyWVmc00nEUql9mhQyv38lDZ8kPZcQVoM=
+github.com/google/go-querystring v1.0.0 h1:Xkwi/a1rcvNg1PPYe5vI8GbeBY/jrVuDX5ASuANWTrk=
+github.com/google/go-querystring v1.0.0/go.mod h1:odCYkC5MyYFN7vkCjXpyrEuKhc/BUO6wN/zVPAxq5ck=
+github.com/google/go-cmp v0.3.1 h1:Xye71clBPdm5HgqGwUkwhbynsUJZhDbS20FvLhQ2izg=
+github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
+github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
@ -39,10 +49,24 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJVlRHBcsciT5bXOrH628=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
+golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45 h1:SVwTIAaPC2U/AvvLNZ2a7OVsmBpC8L5BlwK1whH3hm0=
+golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894 h1:Cz4ceDQGXuKRnVBDTS23GTn/pU5OE2C0WrNTOYK1Uuc=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@ -9,6 +9,7 @@ import (
 	"strings"

 	"github.com/ghodss/yaml"
+	"github.com/google/go-cmp/cmp"
 	"github.com/pkg/errors"
 )

@ -130,6 +131,22 @@ func (c *Config) GetStepConfig(flagValues map[string]interface{}, paramJSON stri
 		stepConfig.mixIn(flagValues, filters.Parameters)
 	}

+	// finally do the condition evaluation post processing
+	for _, p := range parameters {
+		if len(p.Conditions) > 0 {
+			cp := p.Conditions[0].Params[0]
+			dependentValue := stepConfig.Config[cp.Name]
+			if cmp.Equal(dependentValue, cp.Value) && stepConfig.Config[p.Name] == nil {
+				subMapValue := stepConfig.Config[dependentValue.(string)].(map[string]interface{})[p.Name]
+				if subMapValue != nil {
+					stepConfig.Config[p.Name] = subMapValue
+				} else {
+					stepConfig.Config[p.Name] = p.Default
+				}
+			}
+		}
+	}
+
 	return stepConfig, nil
 }

@ -177,7 +194,7 @@ func (s *StepConfig) mixIn(mergeData map[string]interface{}, filter []string) {
 		s.Config = map[string]interface{}{}
 	}

-	s.Config = filterMap(merge(s.Config, mergeData), filter)
+	s.Config = merge(s.Config, filterMap(mergeData, filter))
 }

 func filterMap(data map[string]interface{}, filter []string) map[string]interface{} {
--- a/pkg/config/config_test.go
+++ b/pkg/config/config_test.go
@ -74,6 +74,7 @@ steps:
    p4: p4_step
    px4: px4_step
    p5: p5_step
+    dependentParameter: dependentValue
 stages:
  stage1:
    p5: p5_stage
@ -82,7 +83,7 @@ stages:
 `
 		filters := StepFilters{
 			General:    []string{"p0", "p1", "p2", "p3", "p4"},
-			Steps:      []string{"p0", "p1", "p2", "p3", "p4", "p5"},
+			Steps:      []string{"p0", "p1", "p2", "p3", "p4", "p5", "dependentParameter", "pd1", "dependentValue", "pd2"},
 			Stages:     []string{"p0", "p1", "p2", "p3", "p4", "p5", "p6"},
 			Parameters: []string{"p0", "p1", "p2", "p3", "p4", "p5", "p6", "p7"},
 			Env:        []string{"p0", "p1", "p2", "p3", "p4", "p5"},
@ -97,6 +98,8 @@ steps:
    p1: p1_step_default
    px1: px1_step_default
    p2: p2_step_default
+    dependentValue:
+      pd1: pd1_dependent_default
 `

 		defaults2 := `general:
@ -112,20 +115,49 @@ steps:
 		defaults := []io.ReadCloser{ioutil.NopCloser(strings.NewReader(defaults1)), ioutil.NopCloser(strings.NewReader(defaults2))}

 		myConfig := ioutil.NopCloser(strings.NewReader(testConfig))
-		stepConfig, err := c.GetStepConfig(flags, paramJSON, myConfig, defaults, filters, []StepParameters{}, "stage1", "step1")
+
+		parameterMetadata := []StepParameters{
+			{
+				Name:  "pd1",
+				Scope: []string{"STEPS"},
+				Conditions: []Condition{
+					{
+						Params: []Param{
+							{Name: "dependentParameter", Value: "dependentValue"},
+						},
+					},
+				},
+			},
+			{
+				Name:    "pd2",
+				Default: "pd2_metadata_default",
+				Scope:   []string{"STEPS"},
+				Conditions: []Condition{
+					{
+						Params: []Param{
+							{Name: "dependentParameter", Value: "dependentValue"},
+						},
+					},
+				},
+			},
+		}
+
+		stepConfig, err := c.GetStepConfig(flags, paramJSON, myConfig, defaults, filters, parameterMetadata, "stage1", "step1")

 		assert.Equal(t, nil, err, "error occured but none expected")

 		t.Run("Config", func(t *testing.T) {
 			expected := map[string]string{
-				"p0": "p0_general_default",
-				"p1": "p1_step_default",
-				"p2": "p2_general_default",
-				"p3": "p3_general",
-				"p4": "p4_step",
-				"p5": "p5_stage",
-				"p6": "p6_param",
-				"p7": "p7_flag",
+				"p0":  "p0_general_default",
+				"p1":  "p1_step_default",
+				"p2":  "p2_general_default",
+				"p3":  "p3_general",
+				"p4":  "p4_step",
+				"p5":  "p5_stage",
+				"p6":  "p6_param",
+				"p7":  "p7_flag",
+				"pd1": "pd1_dependent_default",
+				"pd2": "pd2_metadata_default",
 			}
 			for k, v := range expected {
 				t.Run(k, func(t *testing.T) {
--- a/pkg/config/stepmeta.go
+++ b/pkg/config/stepmeta.go
@ -48,6 +48,7 @@ type StepParameters struct {
 	Mandatory       bool        `json:"mandatory,omitempty"`
 	Default         interface{} `json:"default,omitempty"`
 	Aliases         []Alias     `json:"aliases,omitempty"`
+	Conditions      []Condition `json:"conditions,omitempty"`
 }

 // Alias defines a step input parameter alias
@ -58,9 +59,10 @@ type Alias struct {

 // StepResources defines the resources to be provided by the step context, e.g. Jenkins pipeline
 type StepResources struct {
-	Name        string `json:"name"`
-	Description string `json:"description,omitempty"`
-	Type        string `json:"type,omitempty"`
+	Name        string      `json:"name"`
+	Description string      `json:"description,omitempty"`
+	Type        string      `json:"type,omitempty"`
+	Conditions  []Condition `json:"conditions,omitempty"`
 }

 // StepSecrets defines the secrets to be provided by the step context, e.g. Jenkins pipeline
@ -78,14 +80,15 @@ type StepSecrets struct {
 // Container defines an execution container
 type Container struct {
 	//ToDo: check dockerOptions, dockerVolumeBind, containerPortMappings, sidecarOptions, sidecarVolumeBind
-	Command         []string `json:"command"`
-	EnvVars         []EnvVar `json:"env"`
-	Image           string   `json:"image"`
-	ImagePullPolicy string   `json:"imagePullPolicy"`
-	Name            string   `json:"name"`
-	ReadyCommand    string   `json:"readyCommand"`
-	Shell           string   `json:"shell"`
-	WorkingDir      string   `json:"workingDir"`
+	Command         []string    `json:"command"`
+	EnvVars         []EnvVar    `json:"env"`
+	Image           string      `json:"image"`
+	ImagePullPolicy string      `json:"imagePullPolicy"`
+	Name            string      `json:"name"`
+	ReadyCommand    string      `json:"readyCommand"`
+	Shell           string      `json:"shell"`
+	WorkingDir      string      `json:"workingDir"`
+	Conditions      []Condition `json:"conditions,omitempty"`
 }

 // EnvVar defines an environment variable
@ -94,6 +97,18 @@ type EnvVar struct {
 	Value string `json:"value"`
 }

+// Condition defines an condition which decides when the parameter, resource or container is valid
+type Condition struct {
+	ConditionRef string  `json:"conditionRef"`
+	Params       []Param `json:"params"`
+}
+
+// Param defines the parameters serving as inputs to the condition
+type Param struct {
+	Name  string `json:"name"`
+	Value string `json:"value"`
+}
+
 // StepFilters defines the filter parameters for the different sections
 type StepFilters struct {
 	All        []string
@ -123,19 +138,25 @@ func (m *StepData) ReadPipelineStepData(metadata io.ReadCloser) error {
 func (m *StepData) GetParameterFilters() StepFilters {
 	var filters StepFilters
 	for _, param := range m.Spec.Inputs.Parameters {
-		filters.All = append(filters.All, param.Name)
+		parameterKeys := []string{param.Name}
+		for _, condition := range param.Conditions {
+			for _, dependentParam := range condition.Params {
+				parameterKeys = append(parameterKeys, dependentParam.Value)
+			}
+		}
+		filters.All = append(filters.All, parameterKeys...)
 		for _, scope := range param.Scope {
 			switch scope {
 			case "GENERAL":
-				filters.General = append(filters.General, param.Name)
+				filters.General = append(filters.General, parameterKeys...)
 			case "STEPS":
-				filters.Steps = append(filters.Steps, param.Name)
+				filters.Steps = append(filters.Steps, parameterKeys...)
 			case "STAGES":
-				filters.Stages = append(filters.Stages, param.Name)
+				filters.Stages = append(filters.Stages, parameterKeys...)
 			case "PARAMETERS":
-				filters.Parameters = append(filters.Parameters, param.Name)
+				filters.Parameters = append(filters.Parameters, parameterKeys...)
 			case "ENV":
-				filters.Env = append(filters.Env, param.Name)
+				filters.Env = append(filters.Env, parameterKeys...)
 			}
 		}
 	}
@ -156,7 +177,15 @@ func (m *StepData) GetContextParameterFilters() StepFilters {

 	containerFilters := []string{}
 	if len(m.Spec.Containers) > 0 {
-		containerFilters = append(containerFilters, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}...)
+		parameterKeys := []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}
+		for _, container := range m.Spec.Containers {
+			for _, condition := range container.Conditions {
+				for _, dependentParam := range condition.Params {
+					parameterKeys = append(parameterKeys, dependentParam.Value)
+				}
+			}
+		}
+		containerFilters = append(containerFilters, parameterKeys...)
 	}
 	if len(m.Spec.Sidecars) > 0 {
 		//ToDo: support fallback for "dockerName" configuration property -> via aliasing?
@ -175,59 +204,93 @@ func (m *StepData) GetContextParameterFilters() StepFilters {
 // It only supports scenarios with one container and optionally one sidecar
 func (m *StepData) GetContextDefaults(stepName string) (io.ReadCloser, error) {

-	p := map[string]interface{}{}
-
 	//ToDo error handling empty Containers/Sidecars
 	//ToDo handle empty Command
-
+	root := map[string]interface{}{}
 	if len(m.Spec.Containers) > 0 {
-		if len(m.Spec.Containers[0].Command) > 0 {
-			p["containerCommand"] = m.Spec.Containers[0].Command[0]
-		}
-		p["containerName"] = m.Spec.Containers[0].Name
-		p["containerShell"] = m.Spec.Containers[0].Shell
-		p["dockerEnvVars"] = envVarsAsStringSlice(m.Spec.Containers[0].EnvVars)
-		p["dockerImage"] = m.Spec.Containers[0].Image
-		p["dockerName"] = m.Spec.Containers[0].Name
-		p["dockerPullImage"] = m.Spec.Containers[0].ImagePullPolicy != "Never"
-		p["dockerWorkspace"] = m.Spec.Containers[0].WorkingDir
+		for _, container := range m.Spec.Containers {
+			key := ""
+			if len(container.Conditions) > 0 {
+				key = container.Conditions[0].Params[0].Value
+			}
+			p := map[string]interface{}{}
+			if key != "" {
+				root[key] = p
+			} else {
+				p = root
+			}
+			if len(container.Command) > 0 {
+				p["containerCommand"] = container.Command[0]
+			}
+			p["containerName"] = container.Name
+			p["containerShell"] = container.Shell
+			p["dockerEnvVars"] = envVarsAsStringSlice(container.EnvVars)
+			p["dockerImage"] = container.Image
+			p["dockerName"] = container.Name
+			p["dockerPullImage"] = container.ImagePullPolicy != "Never"
+			p["dockerWorkspace"] = container.WorkingDir
+
+			// Ready command not relevant for main runtime container so far
+			//p[] = container.ReadyCommand
+		}

-		// Ready command not relevant for main runtime container so far
-		//p[] = m.Spec.Containers[0].ReadyCommand
 	}

 	if len(m.Spec.Sidecars) > 0 {
 		if len(m.Spec.Sidecars[0].Command) > 0 {
-			p["sidecarCommand"] = m.Spec.Sidecars[0].Command[0]
+			root["sidecarCommand"] = m.Spec.Sidecars[0].Command[0]
 		}
-		p["sidecarEnvVars"] = envVarsAsStringSlice(m.Spec.Sidecars[0].EnvVars)
-		p["sidecarImage"] = m.Spec.Sidecars[0].Image
-		p["sidecarName"] = m.Spec.Sidecars[0].Name
-		p["sidecarPullImage"] = m.Spec.Sidecars[0].ImagePullPolicy != "Never"
-		p["sidecarReadyCommand"] = m.Spec.Sidecars[0].ReadyCommand
-		p["sidecarWorkspace"] = m.Spec.Sidecars[0].WorkingDir
+		root["sidecarEnvVars"] = envVarsAsStringSlice(m.Spec.Sidecars[0].EnvVars)
+		root["sidecarImage"] = m.Spec.Sidecars[0].Image
+		root["sidecarName"] = m.Spec.Sidecars[0].Name
+		root["sidecarPullImage"] = m.Spec.Sidecars[0].ImagePullPolicy != "Never"
+		root["sidecarReadyCommand"] = m.Spec.Sidecars[0].ReadyCommand
+		root["sidecarWorkspace"] = m.Spec.Sidecars[0].WorkingDir
 	}

 	// not filled for now since this is not relevant in Kubernetes case
-	//p["dockerOptions"] = m.Spec.Containers[0].
-	//p["dockerVolumeBind"] = m.Spec.Containers[0].
-	//p["containerPortMappings"] = m.Spec.Sidecars[0].
-	//p["sidecarOptions"] = m.Spec.Sidecars[0].
-	//p["sidecarVolumeBind"] = m.Spec.Sidecars[0].
+	//p["dockerOptions"] = container.
+	//p["dockerVolumeBind"] = container.
+	//root["containerPortMappings"] = m.Spec.Sidecars[0].
+	//root["sidecarOptions"] = m.Spec.Sidecars[0].
+	//root["sidecarVolumeBind"] = m.Spec.Sidecars[0].

 	if len(m.Spec.Inputs.Resources) > 0 {
-		var resources []string
+		keys := []string{}
+		resources := map[string][]string{}
 		for _, resource := range m.Spec.Inputs.Resources {
 			if resource.Type == "stash" {
-				resources = append(resources, resource.Name)
+				key := ""
+				if len(resource.Conditions) > 0 {
+					key = resource.Conditions[0].Params[0].Value
+				}
+				if resources[key] == nil {
+					keys = append(keys, key)
+					resources[key] = []string{}
+				}
+				resources[key] = append(resources[key], resource.Name)
+			}
+		}
+
+		for _, key := range keys {
+			if key == "" {
+				root["stashContent"] = resources[""]
+			} else {
+				if root[key] == nil {
+					root[key] = map[string]interface{}{
+						"stashContent": resources[key],
+					}
+				} else {
+					p := root[key].(map[string]interface{})
+					p["stashContent"] = resources[key]
+				}
 			}
 		}
-		p["stashContent"] = resources
 	}

 	c := Config{
 		Steps: map[string]map[string]interface{}{
-			stepName: p,
+			stepName: root,
 		},
 	}

--- a/pkg/config/stepmeta_test.go
+++ b/pkg/config/stepmeta_test.go
@ -68,6 +68,7 @@ func TestGetParameterFilters(t *testing.T) {
 					{Name: "paramFour", Scope: []string{"PARAMETERS", "ENV"}},
 					{Name: "paramFive", Scope: []string{"ENV"}},
 					{Name: "paramSix"},
+					{Name: "paramSeven", Scope: []string{"GENERAL", "STEPS", "STAGES", "PARAMETERS"}, Conditions: []Condition{{Params: []Param{{Name: "buildTool", Value: "mta"}}}}},
 				},
 			},
 		},
@ -113,17 +114,17 @@ func TestGetParameterFilters(t *testing.T) {
 	}{
 		{
 			Metadata:              metadata1,
-			ExpectedGeneral:       []string{"paramOne"},
-			ExpectedSteps:         []string{"paramOne", "paramTwo"},
-			ExpectedStages:        []string{"paramOne", "paramTwo", "paramThree"},
-			ExpectedParameters:    []string{"paramOne", "paramTwo", "paramThree", "paramFour"},
-			ExpectedEnv:           []string{"paramOne", "paramTwo", "paramThree", "paramFour", "paramFive"},
-			ExpectedAll:           []string{"paramOne", "paramTwo", "paramThree", "paramFour", "paramFive", "paramSix"},
+			ExpectedGeneral:       []string{"paramOne", "paramSeven", "mta"},
+			ExpectedSteps:         []string{"paramOne", "paramTwo", "paramSeven", "mta"},
+			ExpectedStages:        []string{"paramOne", "paramTwo", "paramThree", "paramSeven", "mta"},
+			ExpectedParameters:    []string{"paramOne", "paramTwo", "paramThree", "paramFour", "paramSeven", "mta"},
+			ExpectedEnv:           []string{"paramOne", "paramTwo", "paramThree", "paramFour", "paramFive", "paramSeven", "mta"},
+			ExpectedAll:           []string{"paramOne", "paramTwo", "paramThree", "paramFour", "paramFive", "paramSix", "paramSeven", "mta"},
 			NotExpectedGeneral:    []string{"paramTwo", "paramThree", "paramFour", "paramFive", "paramSix"},
 			NotExpectedSteps:      []string{"paramThree", "paramFour", "paramFive", "paramSix"},
 			NotExpectedStages:     []string{"paramFour", "paramFive", "paramSix"},
 			NotExpectedParameters: []string{"paramFive", "paramSix"},
-			NotExpectedEnv:        []string{"paramSix"},
+			NotExpectedEnv:        []string{"paramSix", "mta"},
 			NotExpectedAll:        []string{},
 		},
 		{
@ -234,6 +235,11 @@ func TestGetContextParameterFilters(t *testing.T) {
 		Spec: StepSpec{
 			Containers: []Container{
 				{Name: "testcontainer"},
+				{Conditions: []Condition{
+					{Params: []Param{
+						{Name: "scanType", Value: "pip"},
+					}},
+				}},
 			},
 		},
 	}
@ -258,12 +264,12 @@ func TestGetContextParameterFilters(t *testing.T) {

 	t.Run("Containers", func(t *testing.T) {
 		filters := metadata2.GetContextParameterFilters()
-		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}, filters.All, "incorrect filter All")
-		assert.NotEqual(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}, filters.General, "incorrect filter General")
-		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}, filters.Steps, "incorrect filter Steps")
-		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}, filters.Stages, "incorrect filter Stages")
-		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}, filters.Parameters, "incorrect filter Parameters")
-		assert.NotEqual(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace"}, filters.Env, "incorrect filter Env")
+		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace", "pip"}, filters.All, "incorrect filter All")
+		assert.NotEqual(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace", "pip"}, filters.General, "incorrect filter General")
+		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace", "pip"}, filters.Steps, "incorrect filter Steps")
+		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace", "pip"}, filters.Stages, "incorrect filter Stages")
+		assert.Equal(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace", "pip"}, filters.Parameters, "incorrect filter Parameters")
+		assert.NotEqual(t, []string{"containerCommand", "containerShell", "dockerEnvVars", "dockerImage", "dockerOptions", "dockerPullImage", "dockerVolumeBind", "dockerWorkspace", "pip"}, filters.Env, "incorrect filter Env")
 	})

 	t.Run("Sidecars", func(t *testing.T) {
@ -287,15 +293,38 @@ func TestGetContextDefaults(t *testing.T) {
 						{
 							Name: "buildDescriptor",
 							Type: "stash",
+							Conditions: []Condition{
+								{Params: []Param{
+									{Name: "scanType", Value: "abc"},
+								}},
+							},
 						},
 						{
 							Name: "source",
 							Type: "stash",
+							Conditions: []Condition{
+								{Params: []Param{
+									{Name: "scanType", Value: "abc"},
+								}},
+							},
 						},
 						{
 							Name: "test",
 							Type: "nonce",
 						},
+						{
+							Name: "test2",
+							Type: "stash",
+							Conditions: []Condition{
+								{Params: []Param{
+									{Name: "scanType", Value: "def"},
+								}},
+							},
+						},
+						{
+							Name: "test3",
+							Type: "stash",
+						},
 					},
 				},
 				Containers: []Container{
@ -339,7 +368,9 @@ func TestGetContextDefaults(t *testing.T) {
 		var d PipelineDefaults
 		d.ReadPipelineDefaults([]io.ReadCloser{cd})

-		assert.Equal(t, []interface{}{"buildDescriptor", "source"}, d.Defaults[0].Steps["testStep"]["stashContent"], "stashContent default not available")
+		assert.Equal(t, []interface{}{"buildDescriptor", "source"}, d.Defaults[0].Steps["testStep"]["abc"].(map[string]interface{})["stashContent"], "stashContent default not available")
+		assert.Equal(t, []interface{}{"test2"}, d.Defaults[0].Steps["testStep"]["def"].(map[string]interface{})["stashContent"], "stashContent default not available")
+		assert.Equal(t, []interface{}{"test3"}, d.Defaults[0].Steps["testStep"]["stashContent"], "stashContent default not available")
 		assert.Equal(t, "test/command", d.Defaults[0].Steps["testStep"]["containerCommand"], "containerCommand default not available")
 		assert.Equal(t, "testcontainer", d.Defaults[0].Steps["testStep"]["containerName"], "containerName default not available")
 		assert.Equal(t, "/bin/bash", d.Defaults[0].Steps["testStep"]["containerShell"], "containerShell default not available")
--- a/pkg/generator/step-metadata.go
+++ b/pkg/generator/step-metadata.go
@ -30,7 +30,7 @@ type stepInfo struct {
 const stepGoTemplate = `package cmd

 import (
-	//"os"
+	{{if .OSImport}}"os"{{end}}

 	"github.com/SAP/jenkins-library/pkg/config"
 	"github.com/SAP/jenkins-library/pkg/log"
@ -148,10 +148,11 @@ func processMetaFiles(metadataFiles []string, openFile func(s string) (io.ReadCl

 		fmt.Printf("Step name: %v\n", stepData.Metadata.Name)

-		err = setDefaultParameters(&stepData)
+		osImport := false
+		osImport, err = setDefaultParameters(&stepData)
 		checkError(err)

-		myStepInfo := getStepInfo(&stepData)
+		myStepInfo := getStepInfo(&stepData, osImport)

 		step := stepTemplate(myStepInfo)
 		err = writeFile(fmt.Sprintf("cmd/%v_generated.go", stepData.Metadata.Name), step, 0644)
@ -172,14 +173,16 @@ func fileWriter(filename string, data []byte, perm os.FileMode) error {
 	return ioutil.WriteFile(filename, data, perm)
 }

-func setDefaultParameters(stepData *config.StepData) error {
+func setDefaultParameters(stepData *config.StepData) (bool, error) {
 	//ToDo: custom function for default handling, support all relevant parameter types
+	osImportRequired := false
 	for k, param := range stepData.Spec.Inputs.Parameters {

 		if param.Default == nil {
 			switch param.Type {
 			case "string":
 				param.Default = fmt.Sprintf("os.Getenv(\"PIPER_%v\")", param.Name)
+				osImportRequired = true
 			case "bool":
 				// ToDo: Check if default should be read from env
 				param.Default = "false"
@ -187,7 +190,7 @@ func setDefaultParameters(stepData *config.StepData) error {
 				// ToDo: Check if default should be read from env
 				param.Default = "[]string{}"
 			default:
-				return fmt.Errorf("Meta data type not set or not known: '%v'", param.Type)
+				return false, fmt.Errorf("Meta data type not set or not known: '%v'", param.Type)
 			}
 		} else {
 			switch param.Type {
@ -202,16 +205,16 @@ func setDefaultParameters(stepData *config.StepData) error {
 			case "[]string":
 				param.Default = fmt.Sprintf("[]string{\"%v\"}", strings.Join(param.Default.([]string), "\", \""))
 			default:
-				return fmt.Errorf("Meta data type not set or not known: '%v'", param.Type)
+				return false, fmt.Errorf("Meta data type not set or not known: '%v'", param.Type)
 			}
 		}

 		stepData.Spec.Inputs.Parameters[k] = param
 	}
-	return nil
+	return osImportRequired, nil
 }

-func getStepInfo(stepData *config.StepData) stepInfo {
+func getStepInfo(stepData *config.StepData, osImport bool) stepInfo {
 	return stepInfo{
 		StepName:         stepData.Metadata.Name,
 		CobraCmdFuncName: fmt.Sprintf("%vCommand", strings.Title(stepData.Metadata.Name)),
@ -220,6 +223,7 @@ func getStepInfo(stepData *config.StepData) stepInfo {
 		Long:             stepData.Metadata.LongDescription,
 		Metadata:         stepData.Spec.Inputs.Parameters,
 		FlagsFunc:        fmt.Sprintf("add%vFlags", strings.Title(stepData.Metadata.Name)),
+		OSImport:         osImport,
 	}
 }

@ -291,6 +295,7 @@ func longName(long string) string {

 func golangName(name string) string {
 	properName := strings.Replace(name, "Api", "API", -1)
+	properName = strings.Replace(properName, "api", "API", -1)
 	properName = strings.Replace(properName, "Url", "URL", -1)
 	properName = strings.Replace(properName, "Id", "ID", -1)
 	properName = strings.Replace(properName, "Json", "JSON", -1)
--- a/pkg/generator/step-metadata_test.go
+++ b/pkg/generator/step-metadata_test.go
@ -112,10 +112,12 @@ func TestSetDefaultParameters(t *testing.T) {
 			"[]string{}",
 		}

-		err := setDefaultParameters(&stepData)
+		osImport, err := setDefaultParameters(&stepData)

 		assert.NoError(t, err, "error occured but none expected")

+		assert.Equal(t, true, osImport, "import of os package required")
+
 		for k, v := range expected {
 			assert.Equal(t, v, stepData.Spec.Inputs.Parameters[k].Default, fmt.Sprintf("default not correct for parameter %v", k))
 		}
@ -145,7 +147,7 @@ func TestSetDefaultParameters(t *testing.T) {
 		}

 		for k, v := range stepData {
-			err := setDefaultParameters(&v)
+			_, err := setDefaultParameters(&v)
 			assert.Error(t, err, fmt.Sprintf("error expected but none occured for parameter %v", k))
 		}
 	})
@ -168,7 +170,7 @@ func TestGetStepInfo(t *testing.T) {
 		},
 	}

-	myStepInfo := getStepInfo(&stepData)
+	myStepInfo := getStepInfo(&stepData, true)

 	assert.Equal(t, "testStep", myStepInfo.StepName, "StepName incorrect")
 	assert.Equal(t, "TestStepCommand", myStepInfo.CobraCmdFuncName, "CobraCmdFuncName incorrect")
@ -177,6 +179,7 @@ func TestGetStepInfo(t *testing.T) {
 	assert.Equal(t, "Long Test description", myStepInfo.Long, "Long incorrect")
 	assert.Equal(t, stepData.Spec.Inputs.Parameters, myStepInfo.Metadata, "Metadata incorrect")
 	assert.Equal(t, "addTestStepFlags", myStepInfo.FlagsFunc, "FlagsFunc incorrect")
+	assert.Equal(t, "addTestStepFlags", myStepInfo.FlagsFunc, "FlagsFunc incorrect")

 }

@ -200,6 +203,7 @@ func TestGolangName(t *testing.T) {
 		expected string
 	}{
 		{input: "testApi", expected: "TestAPI"},
+		{input: "apiTest", expected: "APITest"},
 		{input: "testUrl", expected: "TestURL"},
 		{input: "testId", expected: "TestID"},
 		{input: "testJson", expected: "TestJSON"},
--- a/pkg/generator/testdata/TestProcessMetaFiles/step_code_generated.golden
+++ b/pkg/generator/testdata/TestProcessMetaFiles/step_code_generated.golden
@ -1,7 +1,7 @@
 package cmd

 import (
-	//"os"
+	"os"

 	"github.com/SAP/jenkins-library/pkg/config"
 	"github.com/SAP/jenkins-library/pkg/log"
--- a/pkg/github/github.go
+++ b/pkg/github/github.go
@ -0,0 +1,23 @@
+package github
+
+import (
+	"context"
+
+	"github.com/google/go-github/v28/github"
+	"golang.org/x/oauth2"
+)
+
+//NewClient creates a new GitHub client using an OAuth token for authentication
+func NewClient(token, apiURL, uploadURL string) (context.Context, *github.Client, error) {
+	ctx := context.Background()
+	ts := oauth2.StaticTokenSource(
+		&oauth2.Token{AccessToken: token},
+	)
+	tc := oauth2.NewClient(ctx, ts)
+
+	client, err := github.NewEnterpriseClient(apiURL, uploadURL, tc)
+	if err != nil {
+		return ctx, nil, err
+	}
+	return ctx, client, nil
+}
--- a/resources/metadata/githubrelease.yaml
+++ b/resources/metadata/githubrelease.yaml
@ -0,0 +1,154 @@
+metadata:
+  name: githubPublishRelease
+  description: Publish a release in GitHub
+  longDescription: |
+    This step creates a tag in your GitHub repository together with a release.
+    The release can be filled with text plus additional information like:
+
+    * Closed pull request since last release
+    * Closed issues since last release
+    * Link to delta information showing all commits since last release
+
+    The result looks like
+
+    ![Example release](../images/githubRelease.png)
+spec:
+  inputs:
+    secrets:
+    - name: githubTokenCredentialsId
+      description: Jenkins 'Secret text' credentials ID containing token to authenticate to GitHub.
+      type: jenkins
+    params:
+    - name: addClosedIssues
+      description: 'If set to `true`, closed issues and merged pull-requests since the last release will added below the `releaseBodyHeader`'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: bool
+      default: false
+    - name: addDeltaToLastRelease
+      description: 'If set to `true`, a link will be added to the relese information that brings up all commits since the last release.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: bool
+      default: false
+    - name: assetPath
+      description: Path to a release asset which should be uploaded to the list of release assets.
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+    - name: commitish
+      description: 'Target git commitish for the release'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      default: "master"
+    - name: excludeLabels
+      description: 'Allows to exclude issues with dedicated list of labels.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: '[]string'
+    - name: apiUrl
+      aliases:
+        - name: githubApiUrl
+      description: Set the GitHub API url.
+      scope:
+      - GENERAL
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      default: https://api.github.com
+      mandatory: true
+    - name: owner
+      aliases:
+        - name: githubOrg
+      description: 'Set the GitHub organization.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      mandatory: true
+    - name: repository
+      aliases:
+        - name: githubRepo
+      description: 'Set the GitHub repository.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      mandatory: true
+    - name: serverUrl
+      aliases:
+        - name: githubServerUrl
+      description: 'GitHub server url for end-user access.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      default: https://github.com
+      mandatory: true
+    - name: token
+      aliases:
+        - name: githubToken
+      description: 'GitHub personal access token as per https://help.github.com/en/github/authenticating-to-github/creating-a-personal-access-token-for-the-command-line'
+      scope:
+      - GENERAL
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      mandatory: true
+    - name: uploadUrl
+      aliases:
+        - name: githubUploadUrl
+      description: Set the GitHub API url.
+      scope:
+      - GENERAL
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      default: https://uploads.github.com
+      mandatory: true
+    - name: labels
+      description: 'Labels to include in issue search.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: '[]string'
+    - name: releaseBodyHeader
+      description: Content which will appear for the release.
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+    - name: updateAsset
+      description: Specify if a release asset should be updated only.
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: bool
+    - name: version
+      description: 'Define the version number which will be written as tag as well as release name.'
+      scope:
+      - PARAMETERS
+      - STAGES
+      - STEPS
+      type: string
+      mandatory: true
--- a/src/com/sap/piper/JenkinsUtils.groovy
+++ b/src/com/sap/piper/JenkinsUtils.groovy
@ -7,6 +7,7 @@ import hudson.tasks.junit.TestResultAction
 import jenkins.model.Jenkins

 import org.apache.commons.io.IOUtils
+import org.jenkinsci.plugins.workflow.libs.LibrariesAction
 import org.jenkinsci.plugins.workflow.steps.MissingContextVariableException

@API
@ -108,3 +109,21 @@ String getIssueCommentTriggerAction() {
 def getJobStartedByUserId() {
    return getRawBuild().getCause(hudson.model.Cause.UserIdCause.class)?.getUserId()
 }
+
+@NonCPS
+def getLibrariesInfo() {
+    def libraries = []
+    def build = getRawBuild()
+    def libs = build.getAction(LibrariesAction.class).getLibraries()
+
+    for (def i = 0; i < libs.size(); i++) {
+        Map lib = [:]
+
+        lib['name'] = libs[i].name
+        lib['version'] = libs[i].version
+        lib['trusted'] = libs[i].trusted
+        libraries.add(lib)
+    }
+
+    return libraries
+}
--- a/src/com/sap/piper/PiperGoUtils.groovy
+++ b/src/com/sap/piper/PiperGoUtils.groovy
@ -0,0 +1,63 @@
+package com.sap.piper
+
+class PiperGoUtils implements Serializable {
+
+    private static Script steps
+    private static Utils utils
+
+    PiperGoUtils(Script steps) {
+        this.steps = steps
+        this.utils = new Utils()
+    }
+
+    PiperGoUtils(Script steps, Utils utils) {
+        this.steps = steps
+        this.utils = utils
+    }
+
+    void unstashPiperBin() {
+
+        if (utils.unstash('piper-bin').size() > 0) return
+
+        def libraries = getLibrariesInfo()
+        String version
+        libraries.each {lib ->
+            if (lib.name == 'piper-lib-os') {
+                version = lib.version
+            }
+        }
+
+        def fallbackUrl = 'https://github.com/SAP/jenkins-library/releases/latest/download/piper_master'
+        def piperBinUrl = (version == 'master') ? fallbackUrl : "https://github.com/SAP/jenkins-library/releases/tag/${version}"
+
+        boolean downloaded = downloadGoBinary(piperBinUrl)
+        if (!downloaded) {
+            //Inform that no Piper binary is available for used library branch
+            steps.echo ("Not able to download go binary of Piper for version ${version}")
+            //Fallback to master version & throw error in case this fails
+            steps.retry(5) {
+                if (!downloadGoBinary(fallbackUrl)) {
+                    steps.sleep(2)
+                    steps.error("Download of Piper go binary failed.")
+                }
+            }
+
+        }
+        utils.stashWithMessage('piper-bin', 'failed to stash piper binary', 'piper')
+    }
+
+    List getLibrariesInfo() {
+        return new JenkinsUtils().getLibrariesInfo()
+    }
+
+    private boolean downloadGoBinary(url) {
+
+        def httpStatus = steps.sh(returnStdout: true, script: "curl --insecure --silent --location --write-out '%{http_code}' --output ./piper '${url}'")
+
+        if (httpStatus == '200') {
+            steps.sh(script: 'chmod +x ./piper')
+            return true
+        }
+        return false
+    }
+}
--- a/test/groovy/com/sap/piper/JenkinsUtilsTest.groovy
+++ b/test/groovy/com/sap/piper/JenkinsUtilsTest.groovy
@ -71,6 +71,16 @@ class JenkinsUtilsTest extends BasePiperTest {
                    return triggerCause
                }
            }
+            def getAction(type) {
+                return new Object() {
+                    def getLibraries() {
+                        return [
+                            [name: 'lib1', version: '1', trusted: true],
+                            [name: 'lib2', version: '2', trusted: false],
+                        ]
+                    }
+                }
+            }

        }
        LibraryLoadingTestExecutionListener.prepareObjectInterceptors(rawBuildMock)
@ -130,4 +140,12 @@ class JenkinsUtilsTest extends BasePiperTest {
        userId = null
        assertThat(jenkinsUtils.getJobStartedByUserId(), isEmptyOrNullString())
    }
+
+    @Test
+    void testGetLibrariesInfo() {
+        def libs
+        libs = jenkinsUtils.getLibrariesInfo()
+        assertThat(libs[0], is([name: 'lib1', version: '1', trusted: true]))
+        assertThat(libs[1], is([name: 'lib2', version: '2', trusted: false]))
+    }
 }
--- a/test/groovy/com/sap/piper/PiperGoUtilsTest.groovy
+++ b/test/groovy/com/sap/piper/PiperGoUtilsTest.groovy
@ -0,0 +1,129 @@
+package com.sap.piper
+
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.rules.ExpectedException
+import org.junit.rules.RuleChain
+import util.BasePiperTest
+import util.JenkinsLoggingRule
+import util.JenkinsShellCallRule
+import util.Rules
+
+import static org.hamcrest.Matchers.containsString
+import static org.hamcrest.Matchers.is
+import static org.junit.Assert.assertThat
+
+class PiperGoUtilsTest extends BasePiperTest {
+
+    public ExpectedException exception = ExpectedException.none()
+    public JenkinsShellCallRule shellCallRule = new JenkinsShellCallRule(this)
+    public JenkinsLoggingRule loggingRule = new JenkinsLoggingRule(this)
+
+    @Rule
+    public RuleChain ruleChain = Rules.getCommonRules(this)
+        .around(shellCallRule)
+        .around(exception)
+        .around(loggingRule)
+
+    @Before
+    void init() {
+        helper.registerAllowedMethod("retry", [Integer, Closure], null)
+    }
+
+    @Test
+    void testUnstashPiperBinAvailable() {
+
+        def piperBinStash = 'piper-bin'
+
+        // this mocks utils.unstash
+        helper.registerAllowedMethod("unstash", [String.class], { stashFileName ->
+            if (stashFileName != piperBinStash) {
+                return []
+            }
+            return [piperBinStash]
+        })
+
+        def piperGoUtils = new PiperGoUtils(nullScript, utils)
+
+        piperGoUtils.unstashPiperBin()
+    }
+
+
+    @Test
+    void testUnstashPiperBinMaster() {
+
+        def piperGoUtils = new PiperGoUtils(nullScript, utils)
+        piperGoUtils.metaClass.getLibrariesInfo = {-> return [[name: 'piper-lib-os', version: 'master']]}
+
+        // this mocks utils.unstash - mimic stash not existing
+        helper.registerAllowedMethod("unstash", [String.class], { stashFileName ->
+            return []
+        })
+
+        shellCallRule.setReturnValue('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/latest/download/piper_master\'', '200')
+
+        piperGoUtils.unstashPiperBin()
+        assertThat(shellCallRule.shell.size(), is(2))
+        assertThat(shellCallRule.shell[0].toString(), is('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/latest/download/piper_master\''))
+        assertThat(shellCallRule.shell[1].toString(), is('chmod +x ./piper'))
+    }
+
+    @Test
+    void testUnstashPiperBinNonMaster() {
+
+        def piperGoUtils = new PiperGoUtils(nullScript, utils)
+        piperGoUtils.metaClass.getLibrariesInfo = {-> return [[name: 'piper-lib-os', version: 'testTag']]}
+
+        // this mocks utils.unstash - mimic stash not existing
+        helper.registerAllowedMethod("unstash", [String.class], { stashFileName ->
+            return []
+        })
+
+        shellCallRule.setReturnValue('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/tag/testTag\'', '200')
+
+        piperGoUtils.unstashPiperBin()
+        assertThat(shellCallRule.shell.size(), is(2))
+        assertThat(shellCallRule.shell[0].toString(), is('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/tag/testTag\''))
+        assertThat(shellCallRule.shell[1].toString(), is('chmod +x ./piper'))
+    }
+
+    @Test
+    void testUnstashPiperBinFallback() {
+
+        def piperGoUtils = new PiperGoUtils(nullScript, utils)
+        piperGoUtils.metaClass.getLibrariesInfo = {-> return [[name: 'piper-lib-os', version: 'notAvailable']]}
+
+        shellCallRule.setReturnValue('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/tag/notAvailable\'', '404')
+        shellCallRule.setReturnValue('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/latest/download/piper_master\'', '200')
+
+        // this mocks utils.unstash - mimic stash not existing
+        helper.registerAllowedMethod("unstash", [String.class], { stashFileName ->
+            return []
+        })
+
+        piperGoUtils.unstashPiperBin()
+        assertThat(shellCallRule.shell.size(), is(3))
+        assertThat(shellCallRule.shell[0].toString(), is('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/tag/notAvailable\''))
+        assertThat(shellCallRule.shell[1].toString(), is('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/latest/download/piper_master\''))
+        assertThat(shellCallRule.shell[2].toString(), is('chmod +x ./piper'))
+    }
+
+    @Test
+    void testDownloadFailed() {
+        def piperGoUtils = new PiperGoUtils(nullScript, utils)
+        piperGoUtils.metaClass.getLibrariesInfo = {-> return [[name: 'piper-lib-os', version: 'notAvailable']]}
+
+        shellCallRule.setReturnValue('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/tag/notAvailable\'', '404')
+        shellCallRule.setReturnValue('curl --insecure --silent --location --write-out \'%{http_code}\' --output ./piper \'https://github.com/SAP/jenkins-library/releases/latest/download/piper_master\'', '500')
+
+        helper.registerAllowedMethod("unstash", [String.class], { stashFileName ->
+            return []
+        })
+
+        exception.expectMessage(containsString('Download of Piper go binary failed'))
+        piperGoUtils.unstashPiperBin()
+    }
+}
+
+