Manager: add timeout when fetching job

Add a timeout when fetching a job from the persistence layers.

It's my intention to add more timeouts, so this also introduces some code
to make it easier to test that a context has a deadline set.

internal/manager/api_impl/jobs_query.go

@@ -18,10 +18,8 @@ import (
 // to the HTTP client if it cannot. Returns `nil` in the latter case, and the
 // error returned can then be returned from the Echo handler function.
 func (f *Flamenco) fetchJob(e echo.Context, logger zerolog.Logger, jobID string) (*persistence.Job, error) {
-	// TODO: use a timeout for fetching jobs.
+	ctx, cancel := context.WithTimeout(e.Request().Context(), fetchJobTimeout)
-	// ctx, cancel := context.WithTimeout(e.Request().Context(), fetchJobTimeout)
+	defer cancel()
-	// defer cancel()
-	ctx := e.Request().Context()
 
 	if !uuid.IsValid(jobID) {
 		logger.Debug().Msg("invalid job ID received")

internal/manager/api_impl/jobs_test.go

@@ -14,6 +14,7 @@ import (
 	"git.blender.org/flamenco/internal/manager/last_rendered"
 	"git.blender.org/flamenco/internal/manager/persistence"
 	"git.blender.org/flamenco/pkg/api"
+	"git.blender.org/flamenco/pkg/moremock"
 	"github.com/golang/mock/gomock"
 	"github.com/stretchr/testify/assert"
 )
@@ -408,7 +409,9 @@ func TestSetJobPrio_nonexistentJob(t *testing.T) {
 	jobID := "18a9b096-d77e-438c-9be2-74397038298b"
 	prioUpdate := api.JobPriorityChange{Priority: 47}
 
-	mf.persistence.EXPECT().FetchJob(gomock.Any(), jobID).Return(nil, persistence.ErrJobNotFound)
+	mf.persistence.EXPECT().
+		FetchJob(moremock.ContextWithDeadline(), jobID).
+		Return(nil, persistence.ErrJobNotFound)
 
 	// Do the call.
 	echoCtx := mf.prepareMockedJSONRequest(prioUpdate)
@@ -438,7 +441,7 @@ func TestSetJobPrio(t *testing.T) {
 
 	// Set up expectations.
 	ctx := echoCtx.Request().Context()
-	mf.persistence.EXPECT().FetchJob(ctx, jobID).Return(&dbJob, nil).AnyTimes()
+	mf.persistence.EXPECT().FetchJob(moremock.ContextWithDeadline(), jobID).Return(&dbJob, nil).AnyTimes()
 	jobWithNewPrio := dbJob
 	jobWithNewPrio.Priority = 47
 	mf.persistence.EXPECT().SaveJobPriority(gomock.Not(ctx), &jobWithNewPrio)
@@ -482,7 +485,7 @@ func TestSetJobStatusFailedToRequeueing(t *testing.T) {
 	// Set up expectations.
 	echoCtx := mf.prepareMockedJSONRequest(statusUpdate)
 	ctx := echoCtx.Request().Context()
-	mf.persistence.EXPECT().FetchJob(ctx, jobID).Return(&dbJob, nil)
+	mf.persistence.EXPECT().FetchJob(moremock.ContextWithDeadline(), jobID).Return(&dbJob, nil)
 	mf.stateMachine.EXPECT().JobStatusChange(ctx, &dbJob, statusUpdate.Status, "someone pushed a button")
 	mf.persistence.EXPECT().ClearFailureListOfJob(ctx, &dbJob)
 	mf.persistence.EXPECT().ClearJobBlocklist(ctx, &dbJob)

internal/manager/api_impl/timeouts.go

@@ -0,0 +1,9 @@
+package api_impl
+
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+import "time"
+
+const (
+	fetchJobTimeout = 5 * time.Second
+)

pkg/moremock/context.go

@@ -0,0 +1,36 @@
+package moremock
+
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+import (
+	"context"
+	"time"
+
+	"github.com/golang/mock/gomock"
+)
+
+// ContextWithDeadline returns a gomock matcher to match a context.Context()
+// with a deadline in the future.
+func ContextWithDeadline() gomock.Matcher { return ctxWithDeadlineMatcher{} }
+
+type ctxWithDeadlineMatcher struct{}
+
+// Matches returns whether x is a match.
+func (m ctxWithDeadlineMatcher) Matches(x interface{}) bool {
+	ctx, ok := x.(context.Context)
+	if !ok {
+		return false
+	}
+
+	deadline, ok := ctx.Deadline()
+	if !ok {
+		return false
+	}
+
+	return time.Now().Before(deadline)
+}
+
+// String describes what the matcher matches.
+func (m ctxWithDeadlineMatcher) String() string {
+	return "is context with deadline in the future"
+}

pkg/moremock/context_test.go

@@ -0,0 +1,46 @@
+package moremock
+
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCtxMatcher(t *testing.T) {
+	m := ctxWithDeadlineMatcher{}
+
+	// Non-context types -> No match.
+	assert.False(t, m.Matches(nil))
+	assert.False(t, m.Matches("something else"))
+	var nilValuedInterface context.Context
+	assert.False(t, m.Matches(nilValuedInterface))
+
+	// Context without deadlines -> No match.
+	assert.False(t, m.Matches(context.Background()))
+	assert.False(t, m.Matches(context.TODO()))
+
+	// Deadline in the past -> No match.
+	{
+		past, cancel := context.WithDeadline(context.Background(), time.Now().Add(-1*time.Second))
+		defer cancel()
+		assert.False(t, m.Matches(past))
+	}
+
+	// Deadline in the future -> Match.
+	{
+		future, cancel := context.WithDeadline(context.Background(), time.Now().Add(time.Second))
+		defer cancel()
+		assert.True(t, m.Matches(future))
+	}
+
+	// Timeout in the future -> Match.
+	{
+		future, cancel := context.WithTimeout(context.Background(), time.Second)
+		defer cancel()
+		assert.True(t, m.Matches(future))
+	}
+}

pkg/moremock/moremock.go

@@ -0,0 +1,4 @@
+// Package moremock contains extra matchers for the gomock package.
+//
+// For info on gomock, see https://pkg.go.dev/github.com/golang/mock/gomock
+package moremock