gitlab: Add support for pull requests

internal/providers/gitlab/gitlab.go

@@ -142,5 +142,6 @@ func (c *gitlabClient) GetCredential() provifv1.GitLabCredential {
 
 // SupportsEntity implements the Provider interface
 func (_ *gitlabClient) SupportsEntity(entType minderv1.Entity) bool {
-	return entType == minderv1.Entity_ENTITY_REPOSITORIES
+	return entType == minderv1.Entity_ENTITY_REPOSITORIES ||
+		entType == minderv1.Entity_ENTITY_PULL_REQUESTS
 }

internal/providers/gitlab/manager/webhook_handlers.go

@@ -51,6 +51,8 @@ func (m *providerClassManager) getWebhookEventDispatcher(
 		return m.handleRepoPush
 	case gitlablib.EventTypeTagPush:
 		return m.handleTagPush
+	case gitlablib.EventTypeMergeRequest:
+		return m.handleMergeRequest
 	default:
 		return m.handleNoop
 	}
@@ -98,6 +100,41 @@ func (m *providerClassManager) handleTagPush(l zerolog.Logger, r *http.Request)
 	return m.publishRefreshAndEvalForGitlabProject(l, rawID)
 }
 
+func (m *providerClassManager) handleMergeRequest(l zerolog.Logger, r *http.Request) error {
+	l.Debug().Msg("handling merge request event")
+
+	mergeRequestEvent := gitlablib.MergeEvent{}
+	if err := decodeJSONSafe(r.Body, &mergeRequestEvent); err != nil {
+		l.Error().Err(err).Msg("error decoding merge request event")
+		return fmt.Errorf("error decoding merge request event: %w", err)
+	}
+
+	mrID := mergeRequestEvent.ObjectAttributes.IID
+	if mrID == 0 {
+		return fmt.Errorf("merge request event missing IID")
+	}
+
+	rawID := mergeRequestEvent.Project.ID
+	if rawID == 0 {
+		return fmt.Errorf("merge request event missing project ID")
+	}
+
+	switch {
+	case mergeRequestEvent.ObjectAttributes.Action == "open",
+		mergeRequestEvent.ObjectAttributes.Action == "reopen":
+		return m.publishMergeRequestMessage(rawID, mrID,
+			events.TopicQueueOriginatingEntityAdd)
+	case mergeRequestEvent.ObjectAttributes.Action == "close":
+		return m.publishMergeRequestMessage(rawID, mrID,
+			events.TopicQueueOriginatingEntityDelete)
+	case mergeRequestEvent.ObjectAttributes.Action == "update":
+		return m.publishMergeRequestMessage(rawID, mrID,
+			events.TopicQueueRefreshEntityAndEvaluate)
+	default:
+		return nil
+	}
+}
+
 func (m *providerClassManager) publishRefreshAndEvalForGitlabProject(
 	l zerolog.Logger, rawProjectID int) error {
 	upstreamID := gitlab.FormatRepositoryUpstreamID(rawProjectID)
@@ -134,6 +171,47 @@ func (m *providerClassManager) publishRefreshAndEvalForGitlabProject(
 	return nil
 }
 
+func (m *providerClassManager) publishMergeRequestMessage(mrID int, rawProjectID int, queueTopic string) error {
+	mrUpstreamID := gitlab.FormatPullRequestUpstreamID(mrID)
+	mrProjectID := gitlab.FormatRepositoryUpstreamID(rawProjectID)
+
+	// Form identifying properties
+	identifyingProps, err := properties.NewProperties(map[string]any{
+		properties.PropertyUpstreamID: mrUpstreamID,
+		gitlab.PullRequestProjectID:   mrProjectID,
+	})
+	if err != nil {
+		return fmt.Errorf("error creating identifying properties: %w", err)
+	}
+
+	repoIdentifyingProps, err := properties.NewProperties(map[string]any{
+		properties.PropertyUpstreamID: mrProjectID,
+	})
+	if err != nil {
+		return fmt.Errorf("error creating repo identifying properties: %w", err)
+	}
+
+	// Form message to publish
+	outm := entmsg.NewEntityRefreshAndDoMessage()
+	outm.WithEntity(minderv1.Entity_ENTITY_PULL_REQUESTS, identifyingProps)
+	outm.WithOriginator(minderv1.Entity_ENTITY_REPOSITORIES, repoIdentifyingProps)
+	outm.WithProviderClassHint(gitlab.Class)
+
+	// Convert message for publishing
+	msgID := uuid.New().String()
+	msg := message.NewMessage(msgID, nil)
+	if err := outm.ToMessage(msg); err != nil {
+		return fmt.Errorf("error converting message to protobuf: %w", err)
+	}
+
+	// Publish message
+	if err := m.pub.Publish(queueTopic, msg); err != nil {
+		return fmt.Errorf("error publishing refresh and eval message: %w", err)
+	}
+
+	return nil
+}
+
 func decodeJSONSafe[T any](r io.ReadCloser, v *T) error {
 	rs := wrapSafe(r)
 	defer r.Close()

internal/providers/gitlab/properties.go

@@ -26,6 +26,7 @@ import (
 	minderv1 "github.com/stacklok/minder/pkg/api/protobuf/go/minder/v1"
 )
 
+// Repository Properties
 const (
 	// RepoPropertyProjectName represents the gitlab project
 	RepoPropertyProjectName = "gitlab/project_name"
@@ -43,6 +44,24 @@ const (
 	RepoPropertyHookURL = "gitlab/hook_url"
 )
 
+// Pull Request Properties
+const (
+	// PullRequestProjectID represents the gitlab project ID
+	PullRequestProjectID = "gitlab/project_id"
+	// PullRequestNumber represents the gitlab merge request number
+	PullRequestNumber = "gitlab/merge_request_number"
+	// PullRequestSourceBranch represents the gitlab source branch
+	PullRequestSourceBranch = "gitlab/source_branch"
+	// PullRequestTargetBranch represents the gitlab target branch
+	PullRequestTargetBranch = "gitlab/target_branch"
+	// PullRequestAuthor represents the gitlab author
+	PullRequestAuthor = "gitlab/author"
+	// PullRequestCommitSHA represents the gitlab commit SHA
+	PullRequestCommitSHA = "gitlab/commit_sha"
+	// PullRequestURL represents the gitlab merge request URL
+	PullRequestURL = "gitlab/merge_request_url"
+)
+
 // FetchAllProperties implements the provider interface
 func (c *gitlabClient) FetchAllProperties(
 	ctx context.Context, getByProps *properties.Properties, entType minderv1.Entity, _ *properties.Properties,
@@ -51,7 +70,15 @@ func (c *gitlabClient) FetchAllProperties(
 		return nil, fmt.Errorf("entity type %s not supported", entType)
 	}
 
-	return c.getPropertiesForRepo(ctx, getByProps)
+	//nolint:exhaustive // We only support two entity types for now.
+	switch entType {
+	case minderv1.Entity_ENTITY_REPOSITORIES:
+		return c.getPropertiesForRepo(ctx, getByProps)
+	case minderv1.Entity_ENTITY_PULL_REQUESTS:
+		return c.getPropertiesForPullRequest(ctx, getByProps)
+	default:
+		return nil, fmt.Errorf("entity type %s not supported", entType)
+	}
 }
 
 // FetchProperty implements the provider interface
@@ -71,6 +98,18 @@ func (c *gitlabClient) GetEntityName(entityType minderv1.Entity, props *properti
 		return "", fmt.Errorf("entity type %s not supported", entityType)
 	}
 
+	//nolint:exhaustive // We only support two entity types for now.
+	switch entityType {
+	case minderv1.Entity_ENTITY_REPOSITORIES:
+		return getRepoNameFromProperties(props)
+	case minderv1.Entity_ENTITY_PULL_REQUESTS:
+		return getPullRequestNameFromProperties(props)
+	default:
+		return "", fmt.Errorf("entity type %s not supported", entityType)
+	}
+}
+
+func getRepoNameFromProperties(props *properties.Properties) (string, error) {
 	groupName, err := getStringProp(props, RepoPropertyNamespace)
 	if err != nil {
 		return "", err
@@ -84,6 +123,25 @@ func (c *gitlabClient) GetEntityName(entityType minderv1.Entity, props *properti
 	return formatRepoName(groupName, projectName), nil
 }
 
+func getPullRequestNameFromProperties(props *properties.Properties) (string, error) {
+	groupName, err := getStringProp(props, RepoPropertyNamespace)
+	if err != nil {
+		return "", err
+	}
+
+	projectName, err := getStringProp(props, RepoPropertyProjectName)
+	if err != nil {
+		return "", err
+	}
+
+	iid, err := getStringProp(props, PullRequestNumber)
+	if err != nil {
+		return "", err
+	}
+
+	return formatPullRequestName(groupName, projectName, iid), nil
+}
+
 // PropertiesToProtoMessage implements the ProtoMessageConverter interface
 func (c *gitlabClient) PropertiesToProtoMessage(
 	entType minderv1.Entity, props *properties.Properties,
@@ -92,7 +150,15 @@ func (c *gitlabClient) PropertiesToProtoMessage(
 		return nil, fmt.Errorf("entity type %s is not supported by the gitlab provider", entType)
 	}
 
-	return repoV1FromProperties(props)
+	//nolint:exhaustive // We only support two entity types for now.
+	switch entType {
+	case minderv1.Entity_ENTITY_REPOSITORIES:
+		return repoV1FromProperties(props)
+	case minderv1.Entity_ENTITY_PULL_REQUESTS:
+		return pullRequestV1FromProperties(props)
+	default:
+		return nil, fmt.Errorf("entity type %s not supported", entType)
+	}
 }
 
 // FormatRepositoryUpstreamID returns the upstream ID for a gitlab project
@@ -102,6 +168,13 @@ func FormatRepositoryUpstreamID(id int) string {
 	return fmt.Sprintf("%d", id)
 }
 
+// FormatPullRequestUpstreamID returns the upstream ID for a gitlab merge request
+// This is done so we don't have to deal with conversions in the provider
+// when dealing with entities
+func FormatPullRequestUpstreamID(id int) string {
+	return fmt.Sprintf("%d", id)
+}
+
 func getStringProp(props *properties.Properties, key string) (string, error) {
 	value, err := props.GetProperty(key).AsString()
 	if err != nil {
@@ -114,3 +187,7 @@ func getStringProp(props *properties.Properties, key string) (string, error) {
 func formatRepoName(groupName, projectName string) string {
 	return groupName + "/" + projectName
 }
+
+func formatPullRequestName(groupName, projectName, iid string) string {
+	return fmt.Sprintf("%s/%s/%s", groupName, projectName, iid)
+}