fix: restore the caller's event and inputs in reusable workflow jobs (#1250)

Fixes https://github.com/go-gitea/gitea/issues/38705

Gitea side: https://github.com/go-gitea/gitea/pull/39452

Jobs of a called workflow currently see `gitea.event_name == "workflow_call"`, and their `gitea.event.inputs` is replaced by the caller's `with:`. On GitHub they keep the caller's event, and their `inputs` are the run's `workflow_dispatch` inputs overlaid with the caller's `with:`.

For compatibility with older runners, Gitea keeps sending that form and adds a `gitea_workflow_call` key with the original trigger event name and inputs of the run, and the `inputs` Gitea resolved for the job. When the key is present, the runner restores `gitea.event_name` and `gitea.event.inputs` from it, and uses the resolved `inputs` for the job's expressions and the setup log.

Without that key (older Gitea, or jobs outside called workflows), nothing changes.

Reviewed-on: https://gitea.com/gitea/runner/pulls/1250
Reviewed-by: bircni <bircni@icloud.com>
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: Zettat123 <zettat123@gmail.com>

act/runner/expression.go

@@ -248,6 +248,14 @@ func inputsFromEnv(env map[string]string) map[string]any {
 func getEvaluatorInputs(rc *RunContext, stepInputs map[string]any, ghc *model.GithubContext) map[string]any {
 	inputs := map[string]any{}
 
+	// only a called workflow's job itself takes the inputs Gitea resolved,
+	// composite actions copy its Config but have their own `inputs`
+	if rc.Config.WorkflowCallInputs != nil && rc.Parent == nil {
+		maps.Copy(inputs, rc.Config.WorkflowCallInputs)
+		maps.Copy(inputs, stepInputs)
+		return inputs
+	}
+
 	maps.Copy(inputs, rc.workflowCallInputs)
 	maps.Copy(inputs, stepInputs)
 

act/runner/expression_test.go

@@ -392,6 +392,28 @@ jobs:
 	})
 }
 
+func TestGetEvaluatorInputsResolvedByGitea(t *testing.T) {
+	wf, err := model.ReadWorkflow(strings.NewReader(`
+on:
+  workflow_call:
+    inputs:
+      name: {type: string, default: callee}
+  workflow_dispatch:
+    inputs:
+      name: {type: string}
+`))
+	require.NoError(t, err)
+	config := &Config{Workdir: ".", WorkflowCallInputs: map[string]any{"name": "caller", "target": "dispatch"}}
+	ghc := &model.GithubContext{EventName: "workflow_dispatch", Event: map[string]any{"inputs": map[string]any{"name": "dispatch"}}}
+
+	// the event's own inputs must not override those Gitea resolved
+	job := &RunContext{Config: config, Run: &model.Run{JobID: "job1", Workflow: wf}}
+	assert.Equal(t, map[string]any{"name": "caller", "target": "dispatch"}, getEvaluatorInputs(job, nil, ghc))
+
+	composite := &RunContext{Config: config, Run: &model.Run{JobID: "job1", Workflow: &model.Workflow{}}, Parent: job}
+	assert.Equal(t, map[string]any{"arg": "x"}, getEvaluatorInputs(composite, map[string]any{"arg": "x"}, ghc))
+}
+
 func TestResolveWorkflowCallToleratesMismatchesAndPassesInheritedSecretsVerbatim(t *testing.T) {
 	callerWorkflow, err := model.ReadWorkflow(strings.NewReader(`
 jobs:

act/runner/runner.go

@@ -62,6 +62,7 @@ type Config struct {
 	NoActionPatch                 bool                                          // run actions exactly as published, applying no compatibility patches, see patch_actions.go
 
 	PresetGitHubContext   *model.GithubContext // overrides actor, ref, repository, token and related context fields
+	WorkflowCallInputs    map[string]any       // the `inputs` Gitea resolved for a called workflow's job, nil for other jobs
 	EventJSON             string               // the content of JSON file to use for event.json in containers, overrides EventPath
 	ContainerNamePrefix   string               // the prefix of container name
 	ContainerMaxLifetime  time.Duration        // the max lifetime of job containers

internal/app/run/runner.go

@@ -350,6 +350,25 @@ func (r *Runner) cloneEnvs() map[string]string {
 	return envs
 }
 
+// restoreCalledWorkflowContext undoes Gitea's rewrite of `event_name` and `event.inputs` for older runners,
+// and returns the job's `inputs` from `gitea_workflow_call`, nil if it is not a called workflow's job.
+// See https://github.com/go-gitea/gitea/pull/39452
+func restoreCalledWorkflowContext(task *runnerv1.Task) map[string]any {
+	workflowCall := task.GetContext().GetFields()["gitea_workflow_call"].GetStructValue().GetFields()
+	if workflowCall == nil {
+		return nil
+	}
+	task.Context.Fields["event_name"] = workflowCall["original_event_name"]
+	if event := task.Context.Fields["event"].GetStructValue(); event != nil {
+		if inputs, ok := workflowCall["original_event_inputs"]; ok {
+			event.Fields["inputs"] = inputs
+		} else {
+			delete(event.Fields, "inputs")
+		}
+	}
+	return workflowCall["inputs"].GetStructValue().AsMap()
+}
+
 // getDefaultActionsURL
 // when DEFAULT_ACTIONS_URL == "https://github.com" and GithubMirror is not blank,
 // it should be set to GithubMirror first.
@@ -398,6 +417,7 @@ func (r *Runner) run(ctx context.Context, task *runnerv1.Task, reporter *report.
 		}
 	}()
 
+	workflowCallInputs := restoreCalledWorkflowContext(task)
 	r.reportSetup(reporter, task)
 
 	workflow, jobID, err := generateWorkflow(task)
@@ -536,6 +556,7 @@ func (r *Runner) run(ctx context.Context, task *runnerv1.Task, reporter *report.
 		NoSkipCheckout:       true,
 		DisableActEnv:        r.cfg.Runner.SetActEnv != nil && !*r.cfg.Runner.SetActEnv,
 		PresetGitHubContext:  preset,
+		WorkflowCallInputs:   workflowCallInputs,
 		EventJSON:            string(eventJSON),
 		ContainerNamePrefix:  fmt.Sprintf("GITEA-ACTIONS-TASK-%d", task.Id),
 		ContainerMaxLifetime: maxLifetime,

internal/app/run/runner_test.go

@@ -358,3 +358,48 @@ func TestNewRunnerCacheServiceV2(t *testing.T) {
 		}
 	}
 }
+
+func TestRestoreCalledWorkflowContext(t *testing.T) {
+	newTask := func(workflowCall map[string]any) *runnerv1.Task {
+		values := map[string]any{
+			"event_name": "workflow_call",
+			"event":      map[string]any{"ref": "refs/heads/main", "inputs": map[string]any{"env": "leaf"}},
+		}
+		if workflowCall != nil {
+			values["gitea_workflow_call"] = workflowCall
+		}
+		taskCtx, err := structpb.NewStruct(values)
+		require.NoError(t, err)
+		return &runnerv1.Task{Context: taskCtx}
+	}
+
+	t.Run("dispatched run", func(t *testing.T) {
+		task := newTask(map[string]any{
+			"original_event_name":   "workflow_dispatch",
+			"original_event_inputs": map[string]any{"target": "prod"},
+			"inputs":                map[string]any{"target": "prod", "env": "leaf"},
+		})
+		assert.Equal(t, map[string]any{"target": "prod", "env": "leaf"}, restoreCalledWorkflowContext(task))
+		taskCtx := task.Context.AsMap()
+		assert.Equal(t, "workflow_dispatch", taskCtx["event_name"])
+		assert.Equal(t, map[string]any{"ref": "refs/heads/main", "inputs": map[string]any{"target": "prod"}}, taskCtx["event"])
+		assert.Equal(t, []string{"::group::Inputs", "env: leaf", "target: prod", "::endgroup::"}, inputLines(task.Context.Fields))
+	})
+
+	t.Run("event without inputs", func(t *testing.T) {
+		task := newTask(map[string]any{
+			"original_event_name": "push",
+			"inputs":              map[string]any{"env": "leaf"},
+		})
+		assert.Equal(t, map[string]any{"env": "leaf"}, restoreCalledWorkflowContext(task))
+		taskCtx := task.Context.AsMap()
+		assert.Equal(t, "push", taskCtx["event_name"])
+		assert.Equal(t, map[string]any{"ref": "refs/heads/main"}, taskCtx["event"])
+	})
+
+	t.Run("not a called workflow's job", func(t *testing.T) {
+		task := newTask(nil)
+		assert.Nil(t, restoreCalledWorkflowContext(task))
+		assert.Equal(t, "workflow_call", task.Context.AsMap()["event_name"])
+	})
+}

internal/app/run/setup.go

@@ -56,10 +56,15 @@ func (r *Runner) setupLines(task *runnerv1.Task) []string {
 	return append(lines, "::endgroup::")
 }
 
-// inputLines lists the inputs the run was triggered with, as workflow_dispatch and workflow_call
-// carry them in the event payload. Empty when the event has none.
+// inputLines lists the inputs of the job: those Gitea resolved for a called workflow's job,
+// or the ones a workflow_dispatch event carries in its payload. Empty when there are none.
 func inputLines(fields map[string]*structpb.Value) []string {
 	inputs := fields["event"].GetStructValue().GetFields()["inputs"].GetStructValue().GetFields()
+	// For a called workflow's job, restore its inputs from `gitea_workflow_call`.
+	// See https://github.com/go-gitea/gitea/pull/39452.
+	if workflowCall := fields["gitea_workflow_call"].GetStructValue(); workflowCall != nil {
+		inputs = workflowCall.GetFields()["inputs"].GetStructValue().GetFields()
+	}
 	if len(inputs) == 0 {
 		return nil
 	}