Identify services in startup errors

runner/BUILD.bazel

@@ -20,7 +20,10 @@ go_library(
 
 go_test(
     name = "runner_test",
-    srcs = ["runner_test.go"],
+    srcs = [
+        "runner_test.go",
+        "service_instance_test.go",
+    ],
     embed = [":runner"],
     deps = ["//svclib"],
 )

runner/pgroup_unix.go

@@ -3,13 +3,11 @@
 package runner
 
 import (
-	"fmt"
 	"os/exec"
 	"syscall"
 )
 
 func errnoMeansProcessGone(errno syscall.Errno) bool {
-	fmt.Println("ERRNO", errno)
 	switch errno {
 	case syscall.ESRCH:
 		return true

runner/service_instance.go

@@ -66,7 +66,10 @@ func (s *ServiceInstance) WaitUntilHealthy(ctx context.Context) error {
 	if s.Type == "task" {
 		err := s.waitErrFn()
 		log.Printf("%s completed.\n", coloredLabel)
-		return err
+		if err != nil {
+			return fmt.Errorf("%s exited with error: %w", coloredLabel, err)
+		}
+		return nil
 	}
 
 	sleepDuration, err := time.ParseDuration(s.HealthCheckInterval)
@@ -83,7 +86,7 @@ func (s *ServiceInstance) WaitUntilHealthy(ctx context.Context) error {
 
 	for {
 		if err := s.Error(); err != nil {
-			return err
+			return fmt.Errorf("%s exited with error: %w", coloredLabel, err)
 		}
 
 		if s.isDone() {
@@ -95,7 +98,7 @@ func (s *ServiceInstance) WaitUntilHealthy(ctx context.Context) error {
 		}
 
 		if err := ctx.Err(); err != nil {
-			return err
+			return fmt.Errorf("%s never became healthy: %w", coloredLabel, err)
 		}
 
 		if s.HealthCheck(ctx, expectedStartDuration) {

runner/service_instance_test.go

@@ -0,0 +1,69 @@
+package runner
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+
+	"rules_itest/svclib"
+)
+
+func TestWaitUntilHealthyTaskErrorIncludesLabel(t *testing.T) {
+	wantErr := errors.New("task failed")
+	service := &ServiceInstance{
+		VersionedServiceSpec: svclib.VersionedServiceSpec{ServiceSpec: svclib.ServiceSpec{
+			Type:  "task",
+			Label: "//example:setup",
+		}},
+		waitErrFn: func() error { return wantErr },
+	}
+
+	err := service.WaitUntilHealthy(context.Background())
+	if !errors.Is(err, wantErr) {
+		t.Fatalf("WaitUntilHealthy() error = %v, want wrapped %v", err, wantErr)
+	}
+	if !strings.Contains(err.Error(), service.Label) {
+		t.Fatalf("WaitUntilHealthy() error = %q, want service label %q", err, service.Label)
+	}
+}
+
+func TestWaitUntilHealthyServiceErrorIncludesLabel(t *testing.T) {
+	wantErr := errors.New("service failed")
+	service := &ServiceInstance{
+		VersionedServiceSpec: svclib.VersionedServiceSpec{ServiceSpec: svclib.ServiceSpec{
+			Type:                "service",
+			Label:               "//example:server",
+			HealthCheckInterval: "1ms",
+		}},
+		runErr: wantErr,
+	}
+
+	err := service.WaitUntilHealthy(context.Background())
+	if !errors.Is(err, wantErr) {
+		t.Fatalf("WaitUntilHealthy() error = %v, want wrapped %v", err, wantErr)
+	}
+	if !strings.Contains(err.Error(), service.Label) {
+		t.Fatalf("WaitUntilHealthy() error = %q, want service label %q", err, service.Label)
+	}
+}
+
+func TestWaitUntilHealthyContextErrorIncludesLabel(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	service := &ServiceInstance{
+		VersionedServiceSpec: svclib.VersionedServiceSpec{ServiceSpec: svclib.ServiceSpec{
+			Type:                "service",
+			Label:               "//example:server",
+			HealthCheckInterval: "1ms",
+		}},
+	}
+
+	err := service.WaitUntilHealthy(ctx)
+	if !errors.Is(err, context.Canceled) {
+		t.Fatalf("WaitUntilHealthy() error = %v, want wrapped context cancellation", err)
+	}
+	if !strings.Contains(err.Error(), service.Label) {
+		t.Fatalf("WaitUntilHealthy() error = %q, want service label %q", err, service.Label)
+	}
+}