googleapis/mcp-toolbox · error

failed to create dataproc session client: %w

Error message

failed to create dataproc session client: %w

What it means

The Cloud longrunning.OperationsClient failed to initialize after the batch and session-template clients had already been created; both earlier clients are closed before the error returns so the source does not leak connections.

Source

Thrown at internal/sources/serverlessspark/serverlessspark.go:93

		return nil, fmt.Errorf("failed to create dataproc batch client: %w", err)
	}
	sessionTemplateClient, err := dataproc.NewSessionTemplateControllerClient(ctx, option.WithEndpoint(endpoint), option.WithUserAgent(ua))
	if err != nil {
		batchClient.Close()
		return nil, fmt.Errorf("failed to create dataproc session template client: %w", err)
	}
	opsClient, err := longrunning.NewOperationsClient(ctx, option.WithEndpoint(endpoint), option.WithUserAgent(ua))
	if err != nil {
		batchClient.Close()
		sessionTemplateClient.Close()
		return nil, fmt.Errorf("failed to create longrunning client: %w", err)
	}
	sessionClient, err := dataproc.NewSessionControllerClient(ctx, option.WithEndpoint(endpoint), option.WithUserAgent(ua))
	if err != nil {
		batchClient.Close()
		sessionTemplateClient.Close()
		opsClient.Close()
		return nil, fmt.Errorf("failed to create dataproc session client: %w", err)
	}

	s := &Source{
		Config:                r,
		BatchClient:           batchClient,
		SessionTemplateClient: sessionTemplateClient,
		OpsClient:             opsClient,
		SessionClient:         sessionClient,
	}
	return s, nil
}

var _ sources.Source = &Source{}

type Source struct {
	Config
	BatchClient           *dataproc.BatchControllerClient
	SessionTemplateClient *dataproc.SessionTemplateControllerClient

View on GitHub (pinned to 8cc6e09de2)

Solutions

1. Verify ADC credentials and Dataproc API enablement for the project
2. Check network access to <location>-datapac.googleapis.com:443
3. Retry initialization after transient Google API outages

When it happens

Trigger: Thrown at internal/sources/serverlessspark/serverlessspark.go:93 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/2e08e492b1c8048a. Report an issue: GitHub.