fix(workflow_run_trigger): 204 dispatch is success; resolve run via listing (#41)

Gitea's workflow_dispatch endpoint returns 204 No Content with no Location
header. DispatchWorkflow required that header, so every successful dispatch
errored with "missing Location header" and never yielded a run ID — making
the tool unusable for CAD dispatch.

- DispatchWorkflow now returns error-only; 204 = success, no Location needed.
  Body already carried ref+inputs; kept and covered by test.
- Tool snapshots the newest existing workflow_dispatch run before dispatch,
  then polls ListWorkflowRuns after and returns the newest run with ID above
  that baseline (avoids returning a stale prior run). Falls back to an honest
  "dispatched, run not yet registered" result rather than failing.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/gitea/workflows.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"net/url"
 	"strconv"
-	"strings"
 )
 
 // DispatchWorkflowArgs is the request body for a workflow_dispatch trigger.
@@ -15,42 +14,26 @@ type DispatchWorkflowArgs struct {
 	Inputs map[string]any `json:"inputs,omitempty"`
 }
 
-// WorkflowRunTrigger holds the run ID extracted from the Location header.
-type WorkflowRunTrigger struct {
-	RunID int64
-}
-
-// DispatchWorkflow triggers a workflow_dispatch event and returns the new run ID.
-func (c *Client) DispatchWorkflow(ctx context.Context, owner, repo, workflow string, args DispatchWorkflowArgs) (*WorkflowRunTrigger, error) {
+// DispatchWorkflow triggers a workflow_dispatch event. Gitea returns 204 No
+// Content with NO Location header, so the response carries no run ID — callers
+// resolve the new run separately via ListWorkflowRuns. Returns nil on success.
+func (c *Client) DispatchWorkflow(ctx context.Context, owner, repo, workflow string, args DispatchWorkflowArgs) error {
 	p := fmt.Sprintf("/api/v1/repos/%s/%s/actions/workflows/%s/dispatches", owner, repo, workflow)
 	payload, err := json.Marshal(args)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	resp, err := c.doRaw(ctx, "POST", p, payload)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	if resp.Status != 204 {
 		if mapErr := MapStatus(resp.Status, resp.Body); mapErr != nil {
-			return nil, mapErr
+			return mapErr
 		}
-		return nil, fmt.Errorf("unexpected status %d", resp.Status)
+		return fmt.Errorf("unexpected status %d", resp.Status)
 	}
-	location := resp.Headers.Get("Location")
-	if location == "" {
-		return nil, fmt.Errorf("missing Location header in dispatch response")
-	}
-	// Location is e.g. "/api/v1/repos/o/r/actions/runs/123" — take the last segment.
-	parts := strings.Split(strings.TrimRight(location, "/"), "/")
-	if len(parts) == 0 {
-		return nil, fmt.Errorf("malformed Location: %s", location)
-	}
-	runID, err := strconv.ParseInt(parts[len(parts)-1], 10, 64)
-	if err != nil {
-		return nil, fmt.Errorf("parse run id from %q: %w", location, err)
-	}
-	return &WorkflowRunTrigger{RunID: runID}, nil
+	return nil
 }
 
 // WorkflowRun represents a Gitea Actions run.

internal/gitea/workflows_test.go

@@ -14,6 +14,9 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+// Gitea's dispatch endpoint returns 204 No Content with NO Location header.
+// Dispatch must succeed and forward ref+inputs in the body; the run ID is
+// resolved separately by the tool via ListWorkflowRuns.
 func TestDispatchWorkflow(t *testing.T) {
 	var gotBody []byte
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -22,18 +25,17 @@ func TestDispatchWorkflow(t *testing.T) {
 		var err error
 		gotBody, err = io.ReadAll(r.Body)
 		assert.NoError(t, err)
-		w.Header().Set("Location", "/api/v1/repos/o/r/actions/runs/789")
+		// No Location header — matches real Gitea.
 		w.WriteHeader(http.StatusNoContent)
 	}))
 	defer srv.Close()
 
 	c := gitea.NewClient(srv.URL, "tok")
-	result, err := c.DispatchWorkflow(context.Background(), "o", "r", "ci.yml", gitea.DispatchWorkflowArgs{
+	err := c.DispatchWorkflow(context.Background(), "o", "r", "ci.yml", gitea.DispatchWorkflowArgs{
 		Ref:    "main",
 		Inputs: map[string]any{"env": "prod"},
 	})
 	require.NoError(t, err)
-	assert.Equal(t, int64(789), result.RunID)
 
 	var body map[string]any
 	require.NoError(t, json.Unmarshal(gotBody, &body))
@@ -43,19 +45,6 @@ func TestDispatchWorkflow(t *testing.T) {
 	assert.Equal(t, "prod", inputs["env"])
 }
 
-func TestDispatchWorkflowMissingLocation(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		// 204 but no Location header
-		w.WriteHeader(http.StatusNoContent)
-	}))
-	defer srv.Close()
-
-	c := gitea.NewClient(srv.URL, "tok")
-	_, err := c.DispatchWorkflow(context.Background(), "o", "r", "ci.yml", gitea.DispatchWorkflowArgs{Ref: "main"})
-	require.Error(t, err)
-	assert.Contains(t, err.Error(), "Location")
-}
-
 func TestDispatchWorkflowError404(t *testing.T) {
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusNotFound)
@@ -63,7 +52,7 @@ func TestDispatchWorkflowError404(t *testing.T) {
 	defer srv.Close()
 
 	c := gitea.NewClient(srv.URL, "tok")
-	_, err := c.DispatchWorkflow(context.Background(), "o", "r", "ci.yml", gitea.DispatchWorkflowArgs{Ref: "main"})
+	err := c.DispatchWorkflow(context.Background(), "o", "r", "ci.yml", gitea.DispatchWorkflowArgs{Ref: "main"})
 	require.Error(t, err)
 	assert.True(t, errors.Is(err, gitea.ErrNotFound))
 }

internal/tools/workflow_run_trigger.go

@@ -4,12 +4,22 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"time"
 
 	"gitea.d-ma.be/mathias/gitea-mcp/internal/allowlist"
 	"gitea.d-ma.be/mathias/gitea-mcp/internal/gitea"
 	"gitea.d-ma.be/mathias/gitea-mcp/internal/registry"
 )
 
+// dispatchResolveBudget bounds how many times we poll for the dispatched run to
+// appear, and dispatchResolvePoll is the gap between polls. Gitea returns 204
+// with no run ID, so we list workflow_dispatch runs and take the newest above
+// the pre-dispatch baseline; it may register a beat after the 204.
+const (
+	dispatchResolveBudget = 5
+	dispatchResolvePoll   = time.Second
+)
+
 // WorkflowRunTrigger triggers a Gitea Actions workflow_dispatch run.
 type WorkflowRunTrigger struct {
 	c       *gitea.Client
@@ -68,17 +78,82 @@ func (t *WorkflowRunTrigger) Call(ctx context.Context, raw json.RawMessage) (jso
 		}
 	}
 
-	result, err := t.c.DispatchWorkflow(ctx, args.Owner, args.Name, args.Workflow, gitea.DispatchWorkflowArgs{
+	// Snapshot the newest existing workflow_dispatch run BEFORE dispatching, so we
+	// can tell our fresh run apart from a prior one (Gitea's 204 carries no run ID).
+	baseline := t.newestDispatchRunID(ctx, args.Owner, args.Name, args.Workflow, ref)
+
+	if err := t.c.DispatchWorkflow(ctx, args.Owner, args.Name, args.Workflow, gitea.DispatchWorkflowArgs{
 		Ref:    ref,
 		Inputs: args.Inputs,
-	})
-	if err != nil {
+	}); err != nil {
 		return nil, err
 	}
 
-	htmlURL := fmt.Sprintf("%s/%s/%s/actions/runs/%d", t.baseURL, args.Owner, args.Name, result.RunID)
+	// Resolve the new run by listing workflow_dispatch runs and taking the newest
+	// one whose ID exceeds the baseline. Poll briefly: the run can register a beat
+	// after the 204.
+	var run *gitea.WorkflowRun
+	for i := 0; i < dispatchResolveBudget; i++ {
+		if i > 0 {
+			select {
+			case <-ctx.Done():
+				return nil, ctx.Err()
+			case <-time.After(dispatchResolvePoll):
+			}
+		}
+		if r := t.newestDispatchRun(ctx, args.Owner, args.Name, args.Workflow, ref); r != nil && r.ID > baseline {
+			run = r
+			break
+		}
+	}
+
+	// Dispatch succeeded (204). If the run has not surfaced yet, say so honestly
+	// rather than failing — the workflow IS firing; the caller can list runs.
+	if run == nil {
+		return textOK(map[string]any{
+			"dispatched": true,
+			"note": "dispatch accepted but the run did not register within the resolve window; " +
+				"list recent workflow_dispatch runs to find it",
+		})
+	}
+
+	htmlURL := run.HTMLURL
+	if htmlURL == "" {
+		htmlURL = fmt.Sprintf("%s/%s/%s/actions/runs/%d", t.baseURL, args.Owner, args.Name, run.ID)
+	}
 	return textOK(map[string]any{
-		"run_id":   result.RunID,
-		"html_url": htmlURL,
+		"dispatched": true,
+		"run_id":     run.ID,
+		"html_url":   htmlURL,
 	})
 }
+
+// newestDispatchRun returns the most recent workflow_dispatch run for the given
+// workflow and ref, or nil if none / on listing error (best-effort resolution).
+func (t *WorkflowRunTrigger) newestDispatchRun(ctx context.Context, owner, name, workflow, ref string) *gitea.WorkflowRun {
+	resp, err := t.c.ListWorkflowRuns(ctx, owner, name, gitea.ListWorkflowRunsArgs{
+		Event:    "workflow_dispatch",
+		Workflow: workflow,
+		Branch:   ref,
+		Limit:    20,
+	})
+	if err != nil || resp == nil {
+		return nil
+	}
+	var newest *gitea.WorkflowRun
+	for i := range resp.WorkflowRuns {
+		r := &resp.WorkflowRuns[i]
+		if newest == nil || r.ID > newest.ID {
+			newest = r
+		}
+	}
+	return newest
+}
+
+// newestDispatchRunID is newestDispatchRun's ID, or 0 if none.
+func (t *WorkflowRunTrigger) newestDispatchRunID(ctx context.Context, owner, name, workflow, ref string) int64 {
+	if r := t.newestDispatchRun(ctx, owner, name, workflow, ref); r != nil {
+		return r.ID
+	}
+	return 0
+}

internal/tools/workflow_run_trigger_test.go

@@ -3,8 +3,10 @@ package tools_test
 import (
 	"context"
 	"encoding/json"
+	"io"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"testing"
 
 	"gitea.d-ma.be/mathias/gitea-mcp/internal/allowlist"
@@ -14,10 +16,67 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestWorkflowRunTriggerSuccess(t *testing.T) {
-	// Fake server handles both the repo endpoint (default_branch) and the dispatch endpoint.
+// runsListJSON is a workflow_runs listing body with a single run of the given id.
+func runsListJSON(id int) string {
+	return `{"total_count":1,"workflow_runs":[{"id":` +
+		fmtInt(id) +
+		`,"status":"queued","event":"workflow_dispatch","html_url":"http://gitea.example/mathias/myrepo/actions/runs/` +
+		fmtInt(id) + `"}]}`
+}
+
+func fmtInt(i int) string { b, _ := json.Marshal(i); return string(b) }
+
+// The dispatch endpoint returns 204 with NO Location header (real Gitea). The
+// tool must treat that as success, forward inputs, and resolve the new run by
+// listing workflow_dispatch runs and picking the newest one above the
+// pre-dispatch baseline.
+func TestWorkflowRunTriggerResolvesRunViaListing(t *testing.T) {
+	dispatched := false
+	var gotBody []byte
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch {
+		case r.URL.Path == "/api/v1/repos/mathias/myrepo/actions/workflows/ci.yml/dispatches" && r.Method == http.MethodPost:
+			gotBody, _ = io.ReadAll(r.Body)
+			dispatched = true
+			w.WriteHeader(http.StatusNoContent) // no Location header
+		case strings.HasPrefix(r.URL.Path, "/api/v1/repos/mathias/myrepo/actions/runs"):
+			w.Header().Set("Content-Type", "application/json")
+			if !dispatched {
+				_, _ = w.Write([]byte(`{"total_count":0,"workflow_runs":[]}`)) // baseline: none yet
+				return
+			}
+			_, _ = w.Write([]byte(runsListJSON(100)))
+		default:
+			http.NotFound(w, r)
+		}
+	}))
+	defer srv.Close()
+
+	tool := tools.NewWorkflowRunTrigger(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}), srv.URL)
+	out, err := tool.Call(context.Background(), json.RawMessage(
+		`{"owner":"mathias","name":"myrepo","workflow":"ci.yml","ref":"main","inputs":{"issue_number":"36","harness":"agentsquad"}}`))
+	require.NoError(t, err)
+	assert.True(t, dispatched, "expected POST dispatch")
+
+	// inputs forwarded to the dispatch body
+	var body map[string]any
+	require.NoError(t, json.Unmarshal(gotBody, &body))
+	assert.Equal(t, "main", body["ref"])
+	inputs, ok := body["inputs"].(map[string]any)
+	require.True(t, ok, "inputs must be present in dispatch body")
+	assert.Equal(t, "36", inputs["issue_number"])
+	assert.Equal(t, "agentsquad", inputs["harness"])
+
+	// run id resolved via listing (not a Location header)
+	var result map[string]any
+	require.NoError(t, json.Unmarshal(out, &result))
+	assert.Equal(t, float64(100), result["run_id"])
+	assert.Contains(t, result["html_url"], "/actions/runs/100")
+}
+
+func TestWorkflowRunTriggerDefaultBranch(t *testing.T) {
 	repoHit := false
-	dispatchHit := false
+	dispatched := false
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		switch {
 		case r.URL.Path == "/api/v1/repos/mathias/myrepo" && r.Method == http.MethodGet:
@@ -25,9 +84,15 @@ func TestWorkflowRunTriggerSuccess(t *testing.T) {
 			w.Header().Set("Content-Type", "application/json")
 			_, _ = w.Write([]byte(`{"name":"myrepo","full_name":"mathias/myrepo","default_branch":"main"}`))
 		case r.URL.Path == "/api/v1/repos/mathias/myrepo/actions/workflows/ci.yml/dispatches" && r.Method == http.MethodPost:
-			dispatchHit = true
-			w.Header().Set("Location", "/api/v1/repos/mathias/myrepo/actions/runs/42")
+			dispatched = true
 			w.WriteHeader(http.StatusNoContent)
+		case strings.HasPrefix(r.URL.Path, "/api/v1/repos/mathias/myrepo/actions/runs"):
+			w.Header().Set("Content-Type", "application/json")
+			if !dispatched {
+				_, _ = w.Write([]byte(`{"total_count":0,"workflow_runs":[]}`))
+				return
+			}
+			_, _ = w.Write([]byte(runsListJSON(55)))
 		default:
 			http.NotFound(w, r)
 		}
@@ -38,37 +103,10 @@ func TestWorkflowRunTriggerSuccess(t *testing.T) {
 	out, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"mathias","name":"myrepo","workflow":"ci.yml"}`))
 	require.NoError(t, err)
 	assert.True(t, repoHit, "expected GET /repo for default branch")
-	assert.True(t, dispatchHit, "expected POST dispatch")
 
 	var result map[string]any
 	require.NoError(t, json.Unmarshal(out, &result))
-	assert.Equal(t, float64(42), result["run_id"])
-	assert.Contains(t, result["html_url"], "/mathias/myrepo/actions/runs/42")
-}
-
-func TestWorkflowRunTriggerExplicitRef(t *testing.T) {
-	repoHit := false
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if r.URL.Path == "/api/v1/repos/mathias/myrepo" {
-			repoHit = true
-		}
-		if r.URL.Path == "/api/v1/repos/mathias/myrepo/actions/workflows/ci.yml/dispatches" {
-			w.Header().Set("Location", "/api/v1/repos/mathias/myrepo/actions/runs/99")
-			w.WriteHeader(http.StatusNoContent)
-			return
-		}
-		http.NotFound(w, r)
-	}))
-	defer srv.Close()
-
-	tool := tools.NewWorkflowRunTrigger(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}), srv.URL)
-	out, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"mathias","name":"myrepo","workflow":"ci.yml","ref":"develop"}`))
-	require.NoError(t, err)
-	assert.False(t, repoHit, "should not call GET /repo when ref is provided")
-
-	var result map[string]any
-	require.NoError(t, json.Unmarshal(out, &result))
-	assert.Equal(t, float64(99), result["run_id"])
+	assert.Equal(t, float64(55), result["run_id"])
 }
 
 func TestWorkflowRunTriggerAllowlistRejects(t *testing.T) {