Default settings and options

Default settings

Configure publish and receive (pull) settings to handle messages efficiently.

Publish Settings

Item	Description
DelayThreshold	Sends a publish request to the server at the specified interval. - Default: 100ms.
CountThreshold	Collects and sends messages in batches of the specified size. - Default: 100.
NumGoroutines	Limits the number of concurrently running Goroutines. - Default: 2. - Max: 10.
Timeout	Sets the timeout for server requests. - Default: 60s.
FlowControlSettings	Controls publishing rate through flow control.

Receive Settings

Item	Description
NumGoroutines	Limits the number of concurrently running Goroutines. - Default: 2. - Max: 10.
FlowControlSettings	Controls publishing rate through flow control.

FlowControl Settings

Item	Description
MaxOutstandingMessages	Specifies the maximum number of messages that can be processed in the internal buffer. - Default: 1000.
MaxOutstandingBytes	Specifies the maximum size of messages that can be processed in the internal buffer. - Default: 1G.
LimitExceededBehavior	Defines behavior when limits are exceeded. • SignalError: Returns an error. • Block (Default): Waits until requests can be made without exceeding the limit (*useful for batch processing where individual request latency is not critical). • Ignore: Disables flow control.

Retry

When a gRPC call encounters an error corresponding to a specified status, it will retry the call based on the configured retry settings. Each API includes default retry responses and settings as described below.

Retry error status codes

For more details, refer to GRPC Github.

Item	Description
CANCELLED	The call was canceled, usually by the client.
UNKNOWN	Unknown error, for example, a response from another address that is not defined for this address. - Also applies when the API does not provide detailed error information.
DEADLINE_EXCEEDED	The deadline expired before the operation completed.
NOT_FOUND	Some requested entity (e.g., file or path) was not found.
RESOURCE_EXHAUSTED	Resources are exhausted (e.g., insufficient per-user quota or insufficient disk space).
ABORTED	Operation aborted, often due to concurrency issues such as sequencer check failure or mid-transaction conflicts.
INTERNAL	Internal server error.
UNAVAILABLE	The service is currently unavailable.

Retry settings

Item	Description
Initial	The delay before the first retry. - Adjusted based on the Multiplier value.
Multiplier	Next retry delay = Previous retry delay * Multiplier.
Max	Sets a limit on retry delay. ⚠️ Multiplier cannot cause retry delay to exceed this value.

Publisher Retry Default Setting

API	Retry code	Description	Retry setting
create topic	14	UNAVAILABLE	• Initial : 100ms • Multiplier : 1.3 • Max : 60s
get topic	14	UNAVAILABLE
list topics	14	UNAVAILABLE
list topic subscriptions	14	UNAVAILABLE
update topic	14	UNAVAILABLE
delete topic	14	UNAVAILABLE
publish	1	CANCELLED
	4	DEADLINE_EXCEEDED
	8	RESOURCE_EXHAUSTED
	13	INTERNAL
	14	UNAVAILABLE

Subscriber Retry Default Settings

API	Retry code	Description	Retry setting
create subscription	14	UNAVAILABLE	• Initial : 100ms • Multiplier : 1.3 • Max : 60s
get subscription	14	UNAVAILABLE
list subscriptions	14	UNAVAILABLE
seek	14	UNAVAILABLE
update subscription	14	UNAVAILABLE
delete subscription	14	UNAVAILABLE
modify ack deadline	14	UNAVAILABLE
acknowledge	14	UNAVAILABLE
pull	14	UNAVAILABLE
streaming pull	4	DEADLINE_EXCEEDED
	8	RESOURCE_EXHAUSTED
	13	INTERNAL
	14	UNAVAILABLE

example.

cfg := &pubsub.ClientConfig{
   PublisherCallOptions: &api.PublisherCallOptions{
      Publish: []option.CallOption{
         option.WithRetryOptions(
            option.WithCodes(codes.ResourceExhausted),
            option.WithBackoff(option.Backoff{
               Initial:    100 * time.Millisecond,
               Max:        30000 * time.Millisecond,
               Multiplier: 1.20,
            })),
      },
   },
   SubscriberCallOptions: &api.SubscriberCallOptions{
      StreamingPull: []option.CallOption{
         option.WithRetryOptions(
            option.WithCodes(codes.ResourceExhausted),
            option.WithBackoff(option.Backoff{
               Initial:    100 * time.Millisecond,
               Max:        60000 * time.Millisecond,
               Multiplier: 1.30,
            })),
      },
   },
}
client, err := NewClientWithConfig(ctx, domainID, projectID, conf, opts...)

Logging

Logs for requests and responses (success/failure) in Publish and StreamingPull can be recorded for statistical purposes.

• If a time interval is configured, the success/failure counts for publish and pull operations are logged at each interval.
• To view the logs, the log level must be set to info or higher.

The following default values can be configured for the logger:

Item	Description
Level	Log level - Default: Panic.
Output	Log output - Default: os.Stdout.
StatLogInterval	Time interval for recording logs.

Logging example

conf := &ClientConfig{
    LogOptions: &LogOptions{
        Level: "info",
        Output: os.Stdout,
        StatLogInterval: 1 * time.Second
    }
}
client, err := NewClientWithConfig(ctx, domainID, projectID, conf, opts...)