Add Header User-Agent for request client (#5664)

add Header User-Agent for request client for more precise in recognized the http request from.

close #3778

.cspell.json

@@ -208,6 +208,7 @@
     "unsanitize",
     "Upsert",
     "urfave",
+    "useragent",
     "usecase",
     "varchar",
     "varz",

cli/internal/util.go

@@ -30,6 +30,7 @@ import (
 	"golang.org/x/net/proxy"
 	"golang.org/x/oauth2"
 
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 	"go.woodpecker-ci.org/woodpecker/v3/woodpecker-go/woodpecker"
 )
 
@@ -72,23 +73,27 @@ func NewClient(ctx context.Context, c *cli.Command) (woodpecker.Client, error) {
 
 	trans, _ := client.Transport.(*oauth2.Transport)
 
+	var baseTransport http.RoundTripper
 	if len(socks) != 0 && !socksOff {
 		dialer, err := proxy.SOCKS5("tcp", socks, nil, proxy.Direct)
 		if err != nil {
 			return nil, err
 		}
-		trans.Base = &http.Transport{
+		baseTransport = &http.Transport{
 			TLSClientConfig: tlsConfig,
 			Proxy:           http.ProxyFromEnvironment,
 			Dial:            dialer.Dial,
 		}
 	} else {
-		trans.Base = &http.Transport{
+		baseTransport = &http.Transport{
 			TLSClientConfig: tlsConfig,
 			Proxy:           http.ProxyFromEnvironment,
 		}
 	}
 
+	// Wrap the base transport with User-Agent support
+	trans.Base = httputil.NewUserAgentRoundTripper(baseTransport, "cli")
+
 	return woodpecker.NewClient(server, client), nil
 }
 

pipeline/backend/docker/docker.go

@@ -37,6 +37,7 @@ import (
 	"github.com/urfave/cli/v3"
 
 	backend "go.woodpecker-ci.org/woodpecker/v3/pipeline/backend/types"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 	"go.woodpecker-ci.org/woodpecker/v3/shared/utils"
 )
 
@@ -92,7 +93,9 @@ func httpClientOfOpts(dockerCertPath string, verifyTLS bool) *http.Client {
 	}
 
 	return &http.Client{
-		Transport:     &http.Transport{TLSClientConfig: tlsConf},
+		Transport: httputil.NewUserAgentRoundTripper(
+			&http.Transport{TLSClientConfig: tlsConf},
+			"backend-docker"),
 		CheckRedirect: client.CheckRedirect,
 	}
 }

server/forge/bitbucket/bitbucket.go

@@ -32,6 +32,7 @@ import (
 	"go.woodpecker-ci.org/woodpecker/v3/server/forge/common"
 	forge_types "go.woodpecker-ci.org/woodpecker/v3/server/forge/types"
 	"go.woodpecker-ci.org/woodpecker/v3/server/model"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 	shared_utils "go.woodpecker-ci.org/woodpecker/v3/shared/utils"
 )
 
@@ -449,7 +450,7 @@ func (c *config) newClient(ctx context.Context, u *model.User) *internal.Client
 
 // helper function to return the bitbucket oauth2 client.
 func (c *config) newClientToken(ctx context.Context, accessToken, refreshToken string) *internal.Client {
-	return internal.NewClientToken(
+	client := internal.NewClientToken(
 		ctx,
 		c.api,
 		accessToken,
@@ -459,6 +460,8 @@ func (c *config) newClientToken(ctx context.Context, accessToken, refreshToken s
 			RefreshToken: refreshToken,
 		},
 	)
+	client.Client = httputil.WrapClient(client.Client, "forge-bitbucket")
+	return client
 }
 
 // helper function to return the bitbucket oauth2 config.

server/forge/bitbucketdatacenter/bitbucketdatacenter.go

@@ -34,6 +34,7 @@ import (
 	forge_types "go.woodpecker-ci.org/woodpecker/v3/server/forge/types"
 	"go.woodpecker-ci.org/woodpecker/v3/server/model"
 	"go.woodpecker-ci.org/woodpecker/v3/server/store"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 )
 
 const (
@@ -768,5 +769,6 @@ func (c *client) newClient(ctx context.Context, u *model.User) (*bb.Client, erro
 		AccessToken: u.AccessToken,
 	}
 	client := config.Client(ctx, t)
+	client = httputil.WrapClient(client, "forge-bitbucketdatacenter")
 	return bb.NewClient(c.urlAPI, client)
 }

server/forge/forgejo/forgejo.go

@@ -34,6 +34,7 @@ import (
 	forge_types "go.woodpecker-ci.org/woodpecker/v3/server/forge/types"
 	"go.woodpecker-ci.org/woodpecker/v3/server/model"
 	"go.woodpecker-ci.org/woodpecker/v3/server/store"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 	shared_utils "go.woodpecker-ci.org/woodpecker/v3/shared/utils"
 )
 
@@ -586,12 +587,13 @@ func (c *Forgejo) newClientToken(ctx context.Context, token string) (*forgejo.Cl
 			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
 		}
 	}
-	client, err := forgejo.NewClient(c.url, forgejo.SetToken(token), forgejo.SetHTTPClient(httpClient), forgejo.SetContext(ctx))
+	wrappedClient := httputil.WrapClient(httpClient, "forge-forgejo")
+	client, err := forgejo.NewClient(c.url, forgejo.SetToken(token), forgejo.SetHTTPClient(wrappedClient), forgejo.SetContext(ctx))
 	if err != nil &&
 		(errors.Is(err, &forgejo.ErrUnknownVersion{}) || strings.Contains(err.Error(), "Malformed version")) {
 		// we guess it's a dev forgejo version
 		log.Error().Err(err).Msgf("could not detect forgejo version, assume dev version %s", forgejoDevVersion)
-		client, err = forgejo.NewClient(c.url, forgejo.SetForgejoVersion(forgejoDevVersion), forgejo.SetToken(token), forgejo.SetHTTPClient(httpClient), forgejo.SetContext(ctx))
+		client, err = forgejo.NewClient(c.url, forgejo.SetForgejoVersion(forgejoDevVersion), forgejo.SetToken(token), forgejo.SetHTTPClient(wrappedClient), forgejo.SetContext(ctx))
 	}
 	return client, err
 }

server/forge/gitea/gitea.go

@@ -36,6 +36,7 @@ import (
 	forge_types "go.woodpecker-ci.org/woodpecker/v3/server/forge/types"
 	"go.woodpecker-ci.org/woodpecker/v3/server/model"
 	"go.woodpecker-ci.org/woodpecker/v3/server/store"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 	shared_utils "go.woodpecker-ci.org/woodpecker/v3/shared/utils"
 )
 
@@ -593,12 +594,13 @@ func (c *Gitea) newClientToken(ctx context.Context, token string) (*gitea.Client
 			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
 		}
 	}
-	client, err := gitea.NewClient(c.url, gitea.SetToken(token), gitea.SetHTTPClient(httpClient), gitea.SetContext(ctx))
+	wrappedClient := httputil.WrapClient(httpClient, "forge-gitea")
+	client, err := gitea.NewClient(c.url, gitea.SetToken(token), gitea.SetHTTPClient(wrappedClient), gitea.SetContext(ctx))
 	if err != nil &&
 		(errors.Is(err, &gitea.ErrUnknownVersion{}) || strings.Contains(err.Error(), "Malformed version")) {
 		// we guess it's a dev gitea version
 		log.Error().Err(err).Msgf("could not detect gitea version, assume dev version %s", giteaDevVersion)
-		client, err = gitea.NewClient(c.url, gitea.SetGiteaVersion(giteaDevVersion), gitea.SetToken(token), gitea.SetHTTPClient(httpClient), gitea.SetContext(ctx))
+		client, err = gitea.NewClient(c.url, gitea.SetGiteaVersion(giteaDevVersion), gitea.SetToken(token), gitea.SetHTTPClient(wrappedClient), gitea.SetContext(ctx))
 	}
 	return client, err
 }

server/forge/github/github.go

@@ -37,6 +37,7 @@ import (
 	forge_types "go.woodpecker-ci.org/woodpecker/v3/server/forge/types"
 	"go.woodpecker-ci.org/woodpecker/v3/server/model"
 	"go.woodpecker-ci.org/woodpecker/v3/server/store"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 	"go.woodpecker-ci.org/woodpecker/v3/shared/utils"
 )
 
@@ -469,15 +470,22 @@ func (c *client) newClientToken(ctx context.Context, token string) *github.Clien
 		&oauth2.Token{AccessToken: token},
 	)
 	tc := oauth2.NewClient(ctx, ts)
+
+	// Get the oauth2 transport to set custom base
+	tp, _ := tc.Transport.(*oauth2.Transport)
+
+	baseTransport := &http.Transport{
+		Proxy: http.ProxyFromEnvironment,
+	}
 	if c.SkipVerify {
-		tp, _ := tc.Transport.(*oauth2.Transport)
-		tp.Base = &http.Transport{
-			Proxy: http.ProxyFromEnvironment,
-			TLSClientConfig: &tls.Config{
-				InsecureSkipVerify: true,
-			},
+		baseTransport.TLSClientConfig = &tls.Config{
+			InsecureSkipVerify: true,
 		}
 	}
+
+	// Wrap the base transport with User-Agent support
+	tp.Base = httputil.NewUserAgentRoundTripper(baseTransport, "forge-github")
+
 	client := github.NewClient(tc)
 	client.BaseURL, _ = url.Parse(c.API)
 	return client

server/forge/gitlab/helper.go

@@ -21,6 +21,8 @@ import (
 
 	gitlab "gitlab.com/gitlab-org/api/client-go"
 	"golang.org/x/oauth2"
+
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 )
 
 const (
@@ -33,10 +35,12 @@ func newClient(url, accessToken string, skipVerify bool) (*gitlab.Client, error)
 	return gitlab.NewAuthSourceClient(gitlab.OAuthTokenSource{
 		TokenSource: oauth2.StaticTokenSource(&oauth2.Token{AccessToken: accessToken}),
 	}, gitlab.WithBaseURL(url), gitlab.WithHTTPClient(&http.Client{
-		Transport: &http.Transport{
-			TLSClientConfig: &tls.Config{InsecureSkipVerify: skipVerify},
-			Proxy:           http.ProxyFromEnvironment,
-		},
+		Transport: httputil.NewUserAgentRoundTripper(
+			&http.Transport{
+				TLSClientConfig: &tls.Config{InsecureSkipVerify: skipVerify},
+				Proxy:           http.ProxyFromEnvironment,
+			},
+			"forge-gitlab"),
 	}))
 }
 

server/services/utils/http.go

@@ -30,6 +30,7 @@ import (
 	"github.com/yaronf/httpsign"
 
 	host_matcher "go.woodpecker-ci.org/woodpecker/v3/server/services/utils/hostmatcher"
+	"go.woodpecker-ci.org/woodpecker/v3/shared/httputil"
 )
 
 type Client struct {
@@ -58,12 +59,18 @@ func getHTTPClient(privateKey crypto.PrivateKey, allowedHostListValue string) (*
 		return nil, err
 	}
 
-	client := http.Client{
-		Timeout: timeout,
-		Transport: &http.Transport{
+	// Create base transport with custom User-Agent
+	baseTransport := httputil.NewUserAgentRoundTripper(
+		&http.Transport{
 			TLSClientConfig: &tls.Config{InsecureSkipVerify: false},
 			DialContext:     host_matcher.NewDialContext("extensions", allowedHostMatcher),
 		},
+		"server-extensions",
+	)
+
+	client := http.Client{
+		Timeout:   timeout,
+		Transport: baseTransport,
 	}
 
 	config := httpsign.NewClientConfig().SetSignatureName(pubKeyID).SetSigner(signer)

shared/httputil/useragent.go

@@ -0,0 +1,72 @@
+// Copyright 2024 Woodpecker Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package httputil
+
+import (
+	"fmt"
+	"net/http"
+
+	"go.woodpecker-ci.org/woodpecker/v3/version"
+)
+
+// UserAgentRoundTripper is an http.RoundTripper that sets a custom User-Agent header
+// on all outgoing requests.
+type UserAgentRoundTripper struct {
+	base      http.RoundTripper
+	userAgent string
+}
+
+// NewUserAgentRoundTripper creates a new RoundTripper that adds the Woodpecker User-Agent
+// to all requests. If base is nil, http.DefaultTransport is used.
+func NewUserAgentRoundTripper(base http.RoundTripper, component string) *UserAgentRoundTripper {
+	if base == nil {
+		base = http.DefaultTransport
+	}
+
+	userAgent := fmt.Sprintf("Woodpecker/%s", version.String())
+	if component != "" {
+		userAgent = fmt.Sprintf("%s (%s)", userAgent, component)
+	}
+
+	return &UserAgentRoundTripper{
+		base:      base,
+		userAgent: userAgent,
+	}
+}
+
+// RoundTrip implements the http.RoundTripper interface.
+func (rt *UserAgentRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	// Clone the request to avoid modifying the original
+	reqClone := req.Clone(req.Context())
+
+	// Set the User-Agent header if not already set
+	if reqClone.Header.Get("User-Agent") == "" {
+		reqClone.Header.Set("User-Agent", rt.userAgent)
+	}
+
+	// Execute the request using the base transport
+	return rt.base.RoundTrip(reqClone)
+}
+
+// WrapClient wraps an existing http.Client with the UserAgentRoundTripper.
+// If client is nil, a new client with default settings is created.
+func WrapClient(client *http.Client, component string) *http.Client {
+	if client == nil {
+		client = &http.Client{}
+	}
+
+	client.Transport = NewUserAgentRoundTripper(client.Transport, component)
+	return client
+}

shared/httputil/useragent_test.go

@@ -0,0 +1,169 @@
+// Copyright 2024 Woodpecker Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package httputil
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.woodpecker-ci.org/woodpecker/v3/version"
+)
+
+func TestNewUserAgentRoundTripper(t *testing.T) {
+	t.Run("with custom component", func(t *testing.T) {
+		rt := NewUserAgentRoundTripper(nil, "test-component")
+		assert.NotNil(t, rt)
+		assert.NotNil(t, rt.base)
+		expectedUA := fmt.Sprintf("Woodpecker/%s (test-component)", version.String())
+		assert.Equal(t, expectedUA, rt.userAgent)
+	})
+
+	t.Run("without component", func(t *testing.T) {
+		rt := NewUserAgentRoundTripper(nil, "")
+		assert.NotNil(t, rt)
+		expectedUA := fmt.Sprintf("Woodpecker/%s", version.String())
+		assert.Equal(t, expectedUA, rt.userAgent)
+	})
+
+	t.Run("with custom base transport", func(t *testing.T) {
+		customTransport := &http.Transport{}
+		rt := NewUserAgentRoundTripper(customTransport, "custom")
+		assert.Equal(t, customTransport, rt.base)
+	})
+}
+
+func TestUserAgentRoundTripper_RoundTrip(t *testing.T) {
+	// Create a test server to capture requests
+	var capturedUserAgent string
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		capturedUserAgent = r.Header.Get("User-Agent")
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("OK"))
+	}))
+	defer server.Close()
+
+	t.Run("sets user-agent when not present", func(t *testing.T) {
+		client := &http.Client{
+			Transport: NewUserAgentRoundTripper(nil, "agent"),
+		}
+
+		req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+		assert.NoError(t, err)
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.NotNil(t, resp)
+		defer resp.Body.Close()
+
+		expectedUA := fmt.Sprintf("Woodpecker/%s (agent)", version.String())
+		assert.Equal(t, expectedUA, capturedUserAgent)
+	})
+
+	t.Run("preserves existing user-agent", func(t *testing.T) {
+		client := &http.Client{
+			Transport: NewUserAgentRoundTripper(nil, "agent"),
+		}
+
+		customUA := "CustomUserAgent/1.0"
+		req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+		assert.NoError(t, err)
+		req.Header.Set("User-Agent", customUA)
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.NotNil(t, resp)
+		defer resp.Body.Close()
+
+		assert.Equal(t, customUA, capturedUserAgent)
+	})
+
+	t.Run("does not modify original request", func(t *testing.T) {
+		client := &http.Client{
+			Transport: NewUserAgentRoundTripper(nil, "test"),
+		}
+
+		req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+		assert.NoError(t, err)
+
+		originalUserAgent := req.Header.Get("User-Agent")
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.NotNil(t, resp)
+		defer resp.Body.Close()
+
+		// Original request should remain unchanged
+		assert.Equal(t, originalUserAgent, req.Header.Get("User-Agent"))
+	})
+}
+
+func TestWrapClient(t *testing.T) {
+	t.Run("wraps existing client", func(t *testing.T) {
+		originalClient := &http.Client{}
+		wrappedClient := WrapClient(originalClient, "cli")
+
+		assert.Equal(t, originalClient, wrappedClient)
+		assert.IsType(t, &UserAgentRoundTripper{}, wrappedClient.Transport)
+	})
+
+	t.Run("creates new client when nil", func(t *testing.T) {
+		wrappedClient := WrapClient(nil, "server")
+
+		assert.NotNil(t, wrappedClient)
+		assert.IsType(t, &UserAgentRoundTripper{}, wrappedClient.Transport)
+	})
+
+	t.Run("preserves existing transport", func(t *testing.T) {
+		customTransport := &http.Transport{}
+		originalClient := &http.Client{
+			Transport: customTransport,
+		}
+
+		wrappedClient := WrapClient(originalClient, "test")
+
+		rt, ok := wrappedClient.Transport.(*UserAgentRoundTripper)
+		assert.True(t, ok)
+		assert.Equal(t, customTransport, rt.base)
+	})
+}
+
+func TestIntegration_UserAgentInRealRequest(t *testing.T) {
+	// Test with a real HTTP server
+	var receivedHeaders http.Header
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		receivedHeaders = r.Header.Clone()
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer server.Close()
+
+	client := WrapClient(nil, "integration-test")
+
+	req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+	assert.NoError(t, err)
+
+	resp, err := client.Do(req)
+	assert.NoError(t, err)
+	assert.NotNil(t, resp)
+	defer resp.Body.Close()
+
+	userAgent := receivedHeaders.Get("User-Agent")
+	assert.NotEmpty(t, userAgent)
+	assert.Contains(t, userAgent, "Woodpecker/")
+	assert.Contains(t, userAgent, "(integration-test)")
+}

woodpecker-go/woodpecker/client.go

@@ -23,6 +23,8 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
+
+	"go.woodpecker-ci.org/woodpecker/v3/woodpecker-go/woodpecker/httputil"
 )
 
 const (
@@ -50,12 +52,14 @@ type client struct {
 
 // New returns a client at the specified url.
 func New(uri string) Client {
-	return &client{http.DefaultClient, strings.TrimSuffix(uri, "/")}
+	wrappedClient := httputil.WrapClient(http.DefaultClient, "go-client")
+	return &client{wrappedClient, strings.TrimSuffix(uri, "/")}
 }
 
 // NewClient returns a client at the specified url.
 func NewClient(uri string, cli *http.Client) Client {
-	return &client{cli, strings.TrimSuffix(uri, "/")}
+	wrappedClient := httputil.WrapClient(cli, "go-client")
+	return &client{wrappedClient, strings.TrimSuffix(uri, "/")}
 }
 
 // SetClient sets the http.Client.

woodpecker-go/woodpecker/httputil/useragent.go

@@ -0,0 +1,72 @@
+// Copyright 2024 Woodpecker Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package httputil
+
+import (
+	"fmt"
+	"net/http"
+
+	"go.woodpecker-ci.org/woodpecker/v3/version"
+)
+
+// UserAgentRoundTripper is an http.RoundTripper that sets a custom User-Agent header
+// on all outgoing requests.
+type UserAgentRoundTripper struct {
+	base      http.RoundTripper
+	userAgent string
+}
+
+// NewUserAgentRoundTripper creates a new RoundTripper that adds the Woodpecker User-Agent
+// to all requests. If base is nil, http.DefaultTransport is used.
+func NewUserAgentRoundTripper(base http.RoundTripper, component string) *UserAgentRoundTripper {
+	if base == nil {
+		base = http.DefaultTransport
+	}
+
+	userAgent := fmt.Sprintf("Woodpecker/%s", version.String())
+	if component != "" {
+		userAgent = fmt.Sprintf("%s (%s)", userAgent, component)
+	}
+
+	return &UserAgentRoundTripper{
+		base:      base,
+		userAgent: userAgent,
+	}
+}
+
+// RoundTrip implements the http.RoundTripper interface.
+func (rt *UserAgentRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	// Clone the request to avoid modifying the original
+	reqClone := req.Clone(req.Context())
+
+	// Set the User-Agent header if not already set
+	if reqClone.Header.Get("User-Agent") == "" {
+		reqClone.Header.Set("User-Agent", rt.userAgent)
+	}
+
+	// Execute the request using the base transport
+	return rt.base.RoundTrip(reqClone)
+}
+
+// WrapClient wraps an existing http.Client with the UserAgentRoundTripper.
+// If client is nil, a new client with default settings is created.
+func WrapClient(client *http.Client, component string) *http.Client {
+	if client == nil {
+		client = &http.Client{}
+	}
+
+	client.Transport = NewUserAgentRoundTripper(client.Transport, component)
+	return client
+}

woodpecker-go/woodpecker/httputil/useragent_test.go

@@ -0,0 +1,169 @@
+// Copyright 2024 Woodpecker Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package httputil
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.woodpecker-ci.org/woodpecker/v3/version"
+)
+
+func TestNewUserAgentRoundTripper(t *testing.T) {
+	t.Run("with custom component", func(t *testing.T) {
+		rt := NewUserAgentRoundTripper(nil, "test-component")
+		assert.NotNil(t, rt)
+		assert.NotNil(t, rt.base)
+		expectedUA := fmt.Sprintf("Woodpecker/%s (test-component)", version.String())
+		assert.Equal(t, expectedUA, rt.userAgent)
+	})
+
+	t.Run("without component", func(t *testing.T) {
+		rt := NewUserAgentRoundTripper(nil, "")
+		assert.NotNil(t, rt)
+		expectedUA := fmt.Sprintf("Woodpecker/%s", version.String())
+		assert.Equal(t, expectedUA, rt.userAgent)
+	})
+
+	t.Run("with custom base transport", func(t *testing.T) {
+		customTransport := &http.Transport{}
+		rt := NewUserAgentRoundTripper(customTransport, "custom")
+		assert.Equal(t, customTransport, rt.base)
+	})
+}
+
+func TestUserAgentRoundTripper_RoundTrip(t *testing.T) {
+	// Create a test server to capture requests
+	var capturedUserAgent string
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		capturedUserAgent = r.Header.Get("User-Agent")
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("OK"))
+	}))
+	defer server.Close()
+
+	t.Run("sets user-agent when not present", func(t *testing.T) {
+		client := &http.Client{
+			Transport: NewUserAgentRoundTripper(nil, "agent"),
+		}
+
+		req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+		assert.NoError(t, err)
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.NotNil(t, resp)
+		defer resp.Body.Close()
+
+		expectedUA := fmt.Sprintf("Woodpecker/%s (agent)", version.String())
+		assert.Equal(t, expectedUA, capturedUserAgent)
+	})
+
+	t.Run("preserves existing user-agent", func(t *testing.T) {
+		client := &http.Client{
+			Transport: NewUserAgentRoundTripper(nil, "agent"),
+		}
+
+		customUA := "CustomUserAgent/1.0"
+		req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+		assert.NoError(t, err)
+		req.Header.Set("User-Agent", customUA)
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.NotNil(t, resp)
+		defer resp.Body.Close()
+
+		assert.Equal(t, customUA, capturedUserAgent)
+	})
+
+	t.Run("does not modify original request", func(t *testing.T) {
+		client := &http.Client{
+			Transport: NewUserAgentRoundTripper(nil, "test"),
+		}
+
+		req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+		assert.NoError(t, err)
+
+		originalUserAgent := req.Header.Get("User-Agent")
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.NotNil(t, resp)
+		defer resp.Body.Close()
+
+		// Original request should remain unchanged
+		assert.Equal(t, originalUserAgent, req.Header.Get("User-Agent"))
+	})
+}
+
+func TestWrapClient(t *testing.T) {
+	t.Run("wraps existing client", func(t *testing.T) {
+		originalClient := &http.Client{}
+		wrappedClient := WrapClient(originalClient, "cli")
+
+		assert.Equal(t, originalClient, wrappedClient)
+		assert.IsType(t, &UserAgentRoundTripper{}, wrappedClient.Transport)
+	})
+
+	t.Run("creates new client when nil", func(t *testing.T) {
+		wrappedClient := WrapClient(nil, "server")
+
+		assert.NotNil(t, wrappedClient)
+		assert.IsType(t, &UserAgentRoundTripper{}, wrappedClient.Transport)
+	})
+
+	t.Run("preserves existing transport", func(t *testing.T) {
+		customTransport := &http.Transport{}
+		originalClient := &http.Client{
+			Transport: customTransport,
+		}
+
+		wrappedClient := WrapClient(originalClient, "test")
+
+		rt, ok := wrappedClient.Transport.(*UserAgentRoundTripper)
+		assert.True(t, ok)
+		assert.Equal(t, customTransport, rt.base)
+	})
+}
+
+func TestIntegration_UserAgentInRealRequest(t *testing.T) {
+	// Test with a real HTTP server
+	var receivedHeaders http.Header
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		receivedHeaders = r.Header.Clone()
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer server.Close()
+
+	client := WrapClient(nil, "integration-test")
+
+	req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+	assert.NoError(t, err)
+
+	resp, err := client.Do(req)
+	assert.NoError(t, err)
+	assert.NotNil(t, resp)
+	defer resp.Body.Close()
+
+	userAgent := receivedHeaders.Get("User-Agent")
+	assert.NotEmpty(t, userAgent)
+	assert.Contains(t, userAgent, "Woodpecker/")
+	assert.Contains(t, userAgent, "(integration-test)")
+}