Use context.WithTimeoutCause and context.WithCancelCause for better readability

Author: Amulyam24

cmd/clusterctl/client/repository/repository_gitlab.go

@@ -147,7 +147,7 @@ func (g *gitLabRepository) GetFile(ctx context.Context, version, path string) ([
 		return content, nil
 	}
 
-	timeoutctx, cancel := context.WithTimeout(ctx, 30*time.Second)
+	timeoutctx, cancel := context.WithTimeoutCause(ctx, 30*time.Second, errors.New("http request timeout expired"))
 	defer cancel()
 	request, err := http.NewRequestWithContext(timeoutctx, http.MethodGet, url, http.NoBody)
 	if err != nil {

controllers/clustercache/cluster_accessor_client.go

@@ -228,7 +228,7 @@ func createCachedClient(ctx context.Context, clusterAccessorConfig *clusterAcces
 
 	// Use a context that is independent of the passed in context, so the cache doesn't get stopped
 	// when the passed in context is canceled.
-	cacheCtx, cacheCtxCancel := context.WithCancel(context.Background())
+	cacheCtx, cacheCtxCancel := context.WithCancelCause(context.Background())
 
 	// We need to be able to stop the cache's shared informers, so wrap this in a stoppableCache.
 	cache := &stoppableCache{
@@ -261,7 +261,7 @@ func createCachedClient(ctx context.Context, clusterAccessorConfig *clusterAcces
 	go cache.Start(cacheCtx) //nolint:errcheck
 
 	// Wait until the cache is initially synced.
-	cacheSyncCtx, cacheSyncCtxCancel := context.WithTimeout(ctx, clusterAccessorConfig.Cache.InitialSyncTimeout)
+	cacheSyncCtx, cacheSyncCtxCancel := context.WithTimeoutCause(ctx, clusterAccessorConfig.Cache.InitialSyncTimeout, errors.New("initial sync timeout expired"))
 	defer cacheSyncCtxCancel()
 	if !cache.WaitForCacheSync(cacheSyncCtx) {
 		cache.Stop()
@@ -297,13 +297,13 @@ type clientWithTimeout struct {
 var _ client.Client = &clientWithTimeout{}
 
 func (c clientWithTimeout) Get(ctx context.Context, key client.ObjectKey, obj client.Object, opts ...client.GetOption) error {
-	ctx, cancel := context.WithTimeout(ctx, c.timeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.timeout, errors.New("call timeout expired"))
 	defer cancel()
 	return c.Client.Get(ctx, key, obj, opts...)
 }
 
 func (c clientWithTimeout) List(ctx context.Context, list client.ObjectList, opts ...client.ListOption) error {
-	ctx, cancel := context.WithTimeout(ctx, c.timeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.timeout, errors.New("call timeout expired"))
 	defer cancel()
 	return c.Client.List(ctx, list, opts...)
 }
@@ -314,7 +314,7 @@ type stoppableCache struct {
 
 	lock       sync.Mutex
 	stopped    bool
-	cancelFunc context.CancelFunc
+	cancelFunc context.CancelCauseFunc
 }
 
 // Stop cancels the cache.Cache's context, unless it has already been stopped.
@@ -327,5 +327,5 @@ func (cc *stoppableCache) Stop() {
 	}
 
 	cc.stopped = true
-	cc.cancelFunc()
+	cc.cancelFunc(errors.New("stoppable cache context cancelled"))
 }

controllers/remote/cluster_cache_tracker.go

@@ -514,7 +514,7 @@ func (t *ClusterCacheTracker) createCachedClient(ctx context.Context, config *re
 
 	// Use a context that is independent of the passed in context, so the cache doesn't get stopped
 	// when the passed in context is canceled.
-	cacheCtx, cacheCtxCancel := context.WithCancel(context.Background())
+	cacheCtx, cacheCtxCancel := context.WithCancelCause(context.Background())
 
 	// We need to be able to stop the cache's shared informers, so wrap this in a stoppableCache.
 	cache := &stoppableCache{
@@ -547,7 +547,7 @@ func (t *ClusterCacheTracker) createCachedClient(ctx context.Context, config *re
 	go cache.Start(cacheCtx) //nolint:errcheck
 
 	// Wait until the cache is initially synced
-	cacheSyncCtx, cacheSyncCtxCancel := context.WithTimeout(ctx, initialCacheSyncTimeout)
+	cacheSyncCtx, cacheSyncCtxCancel := context.WithTimeoutCause(ctx, initialCacheSyncTimeout, errors.New("initial sync timeout expired"))
 	defer cacheSyncCtxCancel()
 	if !cache.WaitForCacheSync(cacheSyncCtx) {
 		cache.Stop()
@@ -774,13 +774,13 @@ type clientWithTimeout struct {
 var _ client.Client = &clientWithTimeout{}
 
 func (c clientWithTimeout) Get(ctx context.Context, key client.ObjectKey, obj client.Object, opts ...client.GetOption) error {
-	ctx, cancel := context.WithTimeout(ctx, c.timeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.timeout, errors.New("call timeout expired"))
 	defer cancel()
 	return c.Client.Get(ctx, key, obj, opts...)
 }
 
 func (c clientWithTimeout) List(ctx context.Context, list client.ObjectList, opts ...client.ListOption) error {
-	ctx, cancel := context.WithTimeout(ctx, c.timeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.timeout, errors.New("call timeout expired"))
 	defer cancel()
 	return c.Client.List(ctx, list, opts...)
 }

controllers/remote/stoppable_cache.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"sync"
 
+	"github.com/pkg/errors"
 	"sigs.k8s.io/controller-runtime/pkg/cache"
 )
 
@@ -29,7 +30,7 @@ type stoppableCache struct {
 
 	lock       sync.Mutex
 	stopped    bool
-	cancelFunc context.CancelFunc
+	cancelFunc context.CancelCauseFunc
 }
 
 // Stop cancels the cache.Cache's context, unless it has already been stopped.
@@ -42,5 +43,5 @@ func (cc *stoppableCache) Stop() {
 	}
 
 	cc.stopped = true
-	cc.cancelFunc()
+	cc.cancelFunc(errors.New("stoppable cache context cancelled"))
 }

controlplane/kubeadm/internal/etcd/etcd.go

@@ -176,7 +176,7 @@ func newEtcdClient(ctx context.Context, etcdClient etcd, callTimeout time.Durati
 		return nil, errors.New("etcd client was not configured with any endpoints")
 	}
 
-	ctx, cancel := context.WithTimeout(ctx, callTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, callTimeout, errors.New("call timeout expired"))
 	defer cancel()
 
 	status, err := etcdClient.Status(ctx, endpoints[0])
@@ -200,7 +200,7 @@ func (c *Client) Close() error {
 
 // Members retrieves a list of etcd members.
 func (c *Client) Members(ctx context.Context) ([]*Member, error) {
-	ctx, cancel := context.WithTimeout(ctx, c.CallTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.CallTimeout, errors.New("call timeout expired"))
 	defer cancel()
 
 	response, err := c.EtcdClient.MemberList(ctx)
@@ -231,7 +231,7 @@ func (c *Client) Members(ctx context.Context) ([]*Member, error) {
 
 // MoveLeader moves the leader to the provided member ID.
 func (c *Client) MoveLeader(ctx context.Context, newLeaderID uint64) error {
-	ctx, cancel := context.WithTimeout(ctx, c.CallTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.CallTimeout, errors.New("call timeout expired"))
 	defer cancel()
 
 	_, err := c.EtcdClient.MoveLeader(ctx, newLeaderID)
@@ -240,7 +240,7 @@ func (c *Client) MoveLeader(ctx context.Context, newLeaderID uint64) error {
 
 // RemoveMember removes a given member.
 func (c *Client) RemoveMember(ctx context.Context, id uint64) error {
-	ctx, cancel := context.WithTimeout(ctx, c.CallTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.CallTimeout, errors.New("call timeout expired"))
 	defer cancel()
 
 	_, err := c.EtcdClient.MemberRemove(ctx, id)
@@ -249,7 +249,7 @@ func (c *Client) RemoveMember(ctx context.Context, id uint64) error {
 
 // UpdateMemberPeerURLs updates the list of peer URLs.
 func (c *Client) UpdateMemberPeerURLs(ctx context.Context, id uint64, peerURLs []string) ([]*Member, error) {
-	ctx, cancel := context.WithTimeout(ctx, c.CallTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.CallTimeout, errors.New("call timeout expired"))
 	defer cancel()
 
 	response, err := c.EtcdClient.MemberUpdate(ctx, id, peerURLs)
@@ -267,7 +267,7 @@ func (c *Client) UpdateMemberPeerURLs(ctx context.Context, id uint64, peerURLs [
 
 // Alarms retrieves all alarms on a cluster.
 func (c *Client) Alarms(ctx context.Context) ([]MemberAlarm, error) {
-	ctx, cancel := context.WithTimeout(ctx, c.CallTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, c.CallTimeout, errors.New("call timeout expired"))
 	defer cancel()
 
 	alarmResponse, err := c.EtcdClient.AlarmList(ctx)

exp/runtime/internal/controllers/warmup.go

@@ -69,7 +69,7 @@ func (r *warmupRunnable) Start(ctx context.Context) error {
 	if r.warmupTimeout == 0 {
 		r.warmupTimeout = defaultWarmupTimeout
 	}
-	ctx, cancel := context.WithTimeout(ctx, r.warmupTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, r.warmupTimeout, errors.New("warmup timeout expired"))
 	defer cancel()
 
 	err := wait.PollUntilContextTimeout(ctx, r.warmupInterval, r.warmupTimeout, true, func(ctx context.Context) (done bool, err error) {

hack/tools/internal/log-push/main.go

@@ -170,7 +170,7 @@ func getLogsFromGCS(ctx context.Context, logPath string, logFileRegex *regexp.Re
 	klog.Infof("Getting logs from gs://%s/%s", bucket, folder)
 
 	// Set timeout.
-	ctx, cancel := context.WithTimeout(ctx, 2*time.Minute)
+	ctx, cancel := context.WithTimeoutCause(ctx, 2*time.Minute, errors.New("new client timeout expired"))
 	defer cancel()
 
 	// Create GCS client.

hack/tools/internal/tilt-prepare/main.go

@@ -458,8 +458,8 @@ func runTaskGroup(ctx context.Context, name string, tasks map[string]taskFunctio
 	}(time.Now())
 
 	// Create a context to be used for canceling all the tasks when another fails.
-	ctx, cancel := context.WithCancel(ctx)
-	defer cancel()
+	ctx, cancel := context.WithCancelCause(ctx)
+	defer cancel(errors.New("run task group context cancelled"))
 
 	// Make channels to pass fatal errors in WaitGroup
 	errors := make(chan error)
@@ -483,7 +483,7 @@ func runTaskGroup(ctx context.Context, name string, tasks map[string]taskFunctio
 		break
 	case err := <-errors:
 		// cancel all the running tasks
-		cancel()
+		cancel(err)
 		// consumes all the errors from the channel
 		errList := []error{err}
 	Loop:

internal/controllers/machine/drain/drain.go

@@ -304,7 +304,7 @@ func (d *Helper) EvictPods(ctx context.Context, podDeleteList *PodDeleteList) Ev
 
 	// Trigger evictions for at most 10s. We'll continue on the next reconcile if we hit the timeout.
 	evictionTimeout := 10 * time.Second
-	ctx, cancel := context.WithTimeout(ctx, evictionTimeout)
+	ctx, cancel := context.WithTimeoutCause(ctx, evictionTimeout, errors.New("eviction timeout expired"))
 	defer cancel()
 
 	res := EvictionResult{

internal/runtime/client/client.go

@@ -471,7 +471,7 @@ func httpCall(ctx context.Context, request, response runtime.Object, opts *httpC
 		extensionURL.RawQuery = values.Encode()
 
 		var cancel context.CancelFunc
-		ctx, cancel = context.WithTimeout(ctx, opts.timeout)
+		ctx, cancel = context.WithTimeoutCause(ctx, opts.timeout, errors.New("http request timeout expired"))
 		defer cancel()
 	}