Use context.WithTimeoutCause & context.WithCancelCause instead of context.WithTimeout & context.WithCancel

[sbueringer]

I think we should start using the With*Cause variants of these functions as they allow adding additional context. This should lead to better messages than the standard "context canceled" when a context is canceled.

I took a look at our code base and we have roughly 20 context.WithCancel & 20 context.WithTimeout so it shouldn't be a lot of work to audit all of them and see if we want to use the With*Cause funcs instead

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[sbueringer]

@fabriziopandini @chrischdi @vincepri @enxebre Opinions?

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/lifecycle stale

[sbueringer]

/remove-lifecycle stale

/help

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@sbueringer:
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[Amulyam24]

Hi @sbueringer, I'm interested and would like to work on this issue if this is still relevant. Can you please confirm?

[sbueringer]

It's still relevant. Feel free to go ahead

[Amulyam24]

/assign

[Amulyam24]

Hi @sbueringer, I looked around the repo and as you mentioned there are around 40 instances of context.WithCancel and context.WithTimeout. The change seems pretty minimal with adding errors wherever applicable for additional info after switching to context.With*Cause
I also understand that the switch is not needed at every occurrence.

Is this what you've been looking for or is there anything else that specific that needs to be done?

For example

diff --git a/controllers/clustercache/cluster_accessor_client.go b/controllers/clustercache/cluster_accessor_client.go
index 55fe61ca6..908800133 100644
--- a/controllers/clustercache/cluster_accessor_client.go
+++ b/controllers/clustercache/cluster_accessor_client.go
@@ -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("timed out while waiting for caches to sync"))
        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("timed out while retrieving object in cluster"))
        defer cancel()
        return c.Client.Get(ctx, key, obj, opts...)
 }