All builds now have a per-repository monotonically increasing build number accessible via DRONE_BUILD_NUMBER

and CI_BUILD_NUMBER env variables.

server/datastore/commit.go

@@ -47,6 +47,10 @@ type Commitstore interface {
 	// KillCommits updates all pending or started commits
 	// in the datastore settings the status to killed.
 	KillCommits() error
+
+	// GetCommitBuildNumber retrieves the monotonically increaing build number
+	// from the commit's repo
+	GetBuildNumber(commit *model.Commit) (int64, error)
 }
 
 // GetCommit retrieves a commit from the
@@ -112,3 +116,9 @@ func DelCommit(c context.Context, commit *model.Commit) error {
 func KillCommits(c context.Context) error {
 	return FromContext(c).KillCommits()
 }
+
+// GetBuildNumber retrieves the monotonically increaing build number
+// from the commit's repo
+func GetBuildNumber(c context.Context, commit *model.Commit) (int64, error) {
+	return FromContext(c).GetBuildNumber(commit)
+}

server/datastore/database/commit.go

@@ -1,6 +1,7 @@
 package database
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/drone/drone/shared/model"
@@ -103,6 +104,20 @@ func (db *Commitstore) KillCommits() error {
 	return err
 }
 
+// GetBuildNumber retrieves the build number for a commit.
+func (db *Commitstore) GetBuildNumber(commit *model.Commit) (int64, error) {
+	row := db.QueryRow(rebind(commitGetBuildNumberStmt), commit.ID, commit.RepoID)
+	if row == nil {
+		return 0, fmt.Errorf("Unable to get build number for commit %d", commit.ID)
+	}
+	var bn int64
+	err := row.Scan(&bn)
+	if err != nil {
+		return 0, err
+	}
+	return bn, nil
+}
+
 // Commit table name in database.
 const commitTable = "commits"
 
@@ -194,3 +209,12 @@ const commitKillStmt = `
 UPDATE commits SET commit_status = 'Killed'
 WHERE commit_status IN ('Started', 'Pending');
 `
+
+// SQL statement to retrieve the build number for
+// a commit
+const commitGetBuildNumberStmt = `
+SELECT COUNT(1)
+FROM commits 
+WHERE commit_id <= ? 
+	AND repo_id = ?
+`

server/worker/docker/docker.go

@@ -76,6 +76,7 @@ func (d *Docker) Do(c context.Context, r *worker.Work) {
 	// mark the build as Started and update the database
 	r.Commit.Status = model.StatusStarted
 	r.Commit.Started = time.Now().UTC().Unix()
+
 	datastore.PutCommit(c, r.Commit)
 
 	// notify all listeners that the build is started
@@ -109,6 +110,12 @@ func (d *Docker) Do(c context.Context, r *worker.Work) {
 		}
 	}
 
+	// TODO: handle error better?
+	buildNumber, err := datastore.GetBuildNumber(c, r.Commit)
+	if err != nil {
+		log.Printf("Unable to fetch build number, Err: %s", err.Error())
+	}
+
 	path := r.Repo.Host + "/" + r.Repo.Owner + "/" + r.Repo.Name
 	repo := &repo.Repo{
 		Name:        path,
@@ -118,6 +125,7 @@ func (d *Docker) Do(c context.Context, r *worker.Work) {
 		PR:          r.Commit.PullRequest,
 		Dir:         filepath.Join("/var/cache/drone/src", git.GitPath(script.Git, path)),
 		Depth:       git.GitDepth(script.Git),
+		BuildNumber: buildNumber,
 	}
 
 	priorCommit, _ := datastore.GetCommitPrior(c, r.Commit)

shared/build/build.go

@@ -488,11 +488,12 @@ func (b *Builder) writeBuildScript(dir string) error {
 	f.WriteEnv("DRONE_COMMIT", b.Repo.Commit)
 	f.WriteEnv("DRONE_PR", b.Repo.PR)
 	f.WriteEnv("DRONE_BUILD_DIR", b.Repo.Dir)
+	f.WriteEnv("DRONE_BUILD_NUMBER", fmt.Sprintf("%d", b.Repo.BuildNumber))
 
 	// add environment variables for code coverage
 	// systems, like coveralls.
 	f.WriteEnv("CI_NAME", "DRONE")
-	f.WriteEnv("CI_BUILD_NUMBER", b.Repo.Commit)
+	f.WriteEnv("CI_BUILD_NUMBER", fmt.Sprintf("%d", b.Repo.BuildNumber))
 	f.WriteEnv("CI_BUILD_URL", "")
 	f.WriteEnv("CI_REMOTE", b.Repo.Path)
 	f.WriteEnv("CI_BRANCH", b.Repo.Branch)

shared/build/build_test.go

@@ -525,6 +525,7 @@ func TestWriteBuildScript(t *testing.T) {
 		Path:        "git://github.com/drone/drone.git",
 		Branch:      "master",
 		Commit:      "e7e046b35",
+		BuildNumber: 0,
 		PR:          "123",
 		Dir:         "/var/cache/drone/github.com/drone/drone"}
 	b.writeBuildScript(dir)
@@ -548,8 +549,9 @@ func TestWriteBuildScript(t *testing.T) {
 	f.WriteEnv("DRONE_COMMIT", "e7e046b35")
 	f.WriteEnv("DRONE_PR", "123")
 	f.WriteEnv("DRONE_BUILD_DIR", "/var/cache/drone/github.com/drone/drone")
+	f.WriteEnv("DRONE_BUILD_NUMBER", "0")
 	f.WriteEnv("CI_NAME", "DRONE")
-	f.WriteEnv("CI_BUILD_NUMBER", "e7e046b35")
+	f.WriteEnv("CI_BUILD_NUMBER", "0")
 	f.WriteEnv("CI_BUILD_URL", "")
 	f.WriteEnv("CI_REMOTE", "git://github.com/drone/drone.git")
 	f.WriteEnv("CI_BRANCH", "master")

shared/build/repo/repo.go

@@ -40,6 +40,9 @@ type Repo struct {
 
 	// (optional) The depth of the `git clone` command.
 	Depth int
+
+	// The monotonically increasing build number for this repo
+	BuildNumber int64
 }
 
 // IsRemote returns true if the Repository is located