googleapis/mcp-toolbox · error

failed to create longrunning client: %w

Error message

failed to create longrunning client: %w

What it means

Thrown by the Dataproc source's Config.Initialize when longrunning.NewOperationsClient fails after the cluster controller client was created successfully. The code closes the already-created cluster client before returning to avoid leaks. The wrap preserves the underlying transport or auth error.

Source

Thrown at internal/sources/dataproc/dataproc.go:79

func (r Config) SourceConfigType() string {
	return SourceType
}

func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
	ua, err := util.UserAgentFromContext(ctx)
	if err != nil {
		return nil, fmt.Errorf("error in User Agent retrieval: %s", err)
	}
	endpoint := fmt.Sprintf("%s-dataproc.googleapis.com:443", r.Region)
	client, err := dataproc.NewClusterControllerClient(ctx, option.WithEndpoint(endpoint), option.WithUserAgent(ua))
	if err != nil {
		return nil, fmt.Errorf("failed to create dataproc client: %w", err)
	}
	opsClient, err := longrunning.NewOperationsClient(ctx, option.WithEndpoint(endpoint), option.WithUserAgent(ua))
	if err != nil {
		client.Close()
		return nil, fmt.Errorf("failed to create longrunning client: %w", err)
	}
	jobClient, err := dataproc.NewJobControllerClient(ctx, option.WithEndpoint(endpoint), option.WithUserAgent(ua))
	if err != nil {
		client.Close()
		opsClient.Close()
		return nil, fmt.Errorf("failed to create dataproc job client: %w", err)
	}

	s := &Source{
		Config:    r,
		Client:    client,
		OpsClient: opsClient,
		JobClient: jobClient,
	}
	return s, nil
}

var _ sources.Source = &Source{}

View on GitHub (pinned to 8cc6e09de2)

Solutions

1. Retry initialization — this often follows transient network issues.
2. Verify network connectivity to `<region>-dataproc.googleapis.com:443`.
3. Re-check credentials; inspect the wrapped (%w) cause for the exact error.
4. Confirm the Dataproc API and regional endpoint are healthy for the configured region.

null

null

var src sources.Source
err := retry.Do(func() error {
    var e error
    src, e = cfg.Initialize(ctx, tracer)
    return e
}, retry.Attempts(3), retry.Delay(time.Second))
if err != nil && strings.Contains(err.Error(), "longrunning client") {
    // transient network: alert and surface to user
}

When it happens

Trigger: The Dataproc ClusterControllerClient was created, but the Long Running Operations client creation to the same `<region>-dataproc.googleapis.com:443` endpoint fails — typically due to transient network errors, credential issues surfacing late, or service unavailability.

Common situations: Transient network drops between the two client creations; regional endpoint outage; IAM/token revocation mid-initialization; resource limits exhausting connections.

Related errors

• failed to create dataproc client: %w
• failed to create dataproc job client: %w
• failed to create Dataplex client for project %q: %w
• failed to get instance: %w
• failed to update instance: %w

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/5e42ab73e22aafa1. Report an issue: GitHub.