Add pull request labels as environment variable (#1321)

Closes #1308 

Co-authored-by: Anbraten <anton@ju60.de>

docs/docs/20-usage/20-pipeline-syntax.md

@@ -475,6 +475,13 @@ when:
   - evaluate: 'not (CI_COMMIT_MESSAGE contains "please ignore me")'
 ```
 
+Run on pull requests with the label `deploy`:
+
+```yaml
+when:
+  - evaluate: 'CI_COMMIT_PULL_REQUEST_LABELS contains "deploy"'
+```
+
 ### `group` - Parallel execution
 
 Woodpecker supports parallel step execution for same-machine fan-in and fan-out. Parallel steps are configured using the `group` attribute. This instructs the pipeline runner to execute the named group in parallel.

docs/docs/20-usage/50-environment.md

@@ -68,6 +68,7 @@ This is the reference list of all environment variables available to your pipeli
 | `CI_COMMIT_TARGET_BRANCH`        | commit target branch                                                                         |
 | `CI_COMMIT_TAG`                  | commit tag name (empty if event is not `tag`)                                                |
 | `CI_COMMIT_PULL_REQUEST`         | commit pull request number (empty if event is not `pull_request`)                            |
+| `CI_COMMIT_PULL_REQUEST_LABELS`  | labels assigned to pull request (empty if event is not `pull_request`)                       |
 | `CI_COMMIT_LINK`                 | commit link in forge                                                                         |
 | `CI_COMMIT_MESSAGE`              | commit message                                                                               |
 | `CI_COMMIT_AUTHOR`               | commit author username                                                                       |

pipeline/frontend/metadata.go

@@ -86,6 +86,7 @@ type (
 		Message           string   `json:"message,omitempty"`
 		Author            Author   `json:"author,omitempty"`
 		ChangedFiles      []string `json:"changed_files,omitempty"`
+		PullRequestLabels []string `json:"labels,omitempty"`
 	}
 
 	// Author defines runtime metadata for a commit author.
@@ -167,6 +168,7 @@ func (m *Metadata) Environ() map[string]string {
 		"CI_COMMIT_AUTHOR_AVATAR":       m.Curr.Commit.Author.Avatar,
 		"CI_COMMIT_TAG":                 "", // will be set if event is tag
 		"CI_COMMIT_PULL_REQUEST":        "", // will be set if event is pr
+		"CI_COMMIT_PULL_REQUEST_LABELS": "", // will be set if event is pr
 
 		"CI_PIPELINE_NUMBER":        strconv.FormatInt(m.Curr.Number, 10),
 		"CI_PIPELINE_PARENT":        strconv.FormatInt(m.Curr.Parent, 10),
@@ -244,6 +246,7 @@ func (m *Metadata) Environ() map[string]string {
 	}
 	if m.Curr.Event == EventPull {
 		params["CI_COMMIT_PULL_REQUEST"] = pullRegexp.FindString(m.Curr.Commit.Ref)
+		params["CI_COMMIT_PULL_REQUEST_LABELS"] = strings.Join(m.Curr.Commit.PullRequestLabels, ",")
 	}
 
 	return params

pipeline/stepBuilder.go

@@ -389,6 +389,7 @@ func metadataPipelineFromModelPipeline(pipeline *model.Pipeline, includeParent b
 				Avatar: pipeline.Avatar,
 			},
 			ChangedFiles:      pipeline.ChangedFiles,
+			PullRequestLabels: pipeline.PullRequestLabels,
 		},
 		Cron: cron,
 	}

server/forge/gitea/helper.go

@@ -160,6 +160,7 @@ func pipelineFromPullRequest(hook *pullRequestHook) *model.Pipeline {
 			hook.PullRequest.Head.Ref,
 			hook.PullRequest.Base.Ref,
 		),
+		PullRequestLabels: convertLabels(hook.PullRequest.Labels),
 	}
 	return pipeline
 }
@@ -229,3 +230,11 @@ func matchingHooks(hooks []*gitea.Hook, rawurl string) *gitea.Hook {
 	}
 	return nil
 }
+
+func convertLabels(from []*gitea.Label) []string {
+	labels := make([]string, len(from))
+	for i, label := range from {
+		labels[i] = label.Name
+	}
+	return labels
+}

server/forge/github/convert.go

@@ -164,3 +164,13 @@ func convertRepoHook(eventRepo *github.PushEventRepository) *model.Repo {
 	}
 	return repo
 }
+
+// covertLabels is a helper function used to convert a GitHub label list to
+// the common Woodpecker label structure.
+func convertLabels(from []*github.Label) []string {
+	labels := make([]string, len(from))
+	for i, label := range from {
+		labels[i] = *label.Name
+	}
+	return labels
+}

server/forge/github/parse.go

@@ -170,6 +170,7 @@ func parsePullHook(hook *github.PullRequestEvent, merge bool) (*github.PullReque
 			hook.GetPullRequest().GetHead().GetRef(),
 			hook.GetPullRequest().GetBase().GetRef(),
 		),
+		PullRequestLabels: convertLabels(hook.GetPullRequest().Labels),
 	}
 	if merge {
 		pipeline.Ref = fmt.Sprintf(mergeRefs, hook.GetPullRequest().GetNumber())

server/forge/gitlab/convert.go

@@ -129,6 +129,7 @@ func convertMergeRequestHook(hook *gitlab.MergeEvent, req *http.Request) (int, *
 
 	pipeline.Title = obj.Title
 	pipeline.Link = obj.URL
+	pipeline.PullRequestLabels = convertLabels(hook.Labels)
 
 	return obj.IID, repo, pipeline, nil
 }
@@ -250,3 +251,11 @@ func extractFromPath(str string) (string, string, error) {
 	}
 	return s[0], s[1], nil
 }
+
+func convertLabels(from []*gitlab.Label) []string {
+	labels := make([]string, len(from))
+	for i, label := range from {
+		labels[i] = label.Name
+	}
+	return labels
+}

server/model/pipeline.go

@@ -52,6 +52,7 @@ type Pipeline struct {
 	Files               []*File           `json:"files,omitempty"         xorm:"-"`
 	ChangedFiles        []string          `json:"changed_files,omitempty" xorm:"json 'changed_files'"`
 	AdditionalVariables map[string]string `json:"variables,omitempty"     xorm:"json 'additional_variables'"`
+	PullRequestLabels   []string          `json:"pr_labels,omitempty"     xorm:"json 'pr_labels'"`
 }
 
 // TableName return database table name for xorm