SDK node configuration and management module.

The SDK node is a top level SDK library supervisor process running on the Erlang node.

SDK node responsibilities:

• configure and start SDK node-level statistics telemetry poller,
• configure SDK node-level fixed window rate limiter time windows,
• configure and attach SDK-wide telemetry events handlers,
• configure SDK node-wide options, such as scope_config,
• configure, start and supervise workflow execution scope processes,
• configure, start and supervise SDK cluster processes.

SDK Configuration

node - property list or map with SDK node configuration options as described in the SDK Node Configuration section. Example:

Elixir

node: %{:scope_config => [{:cluster_1, 5}]}

Erlang

{node, #{scope_config => [{cluster_1, 5}]}}

clusters - property list containing SDK cluster configurations. The proplist key is a cluster name t:temporal_sdk_cluster:cluster_name/0, and the proplist value is a cluster configuration defined as a map or proplist. Refer to m:temporal_sdk_cluster for details about SDK cluster configuration.

Example temporal_sdk configuration with one SDK cluster cluster_1 and workflow execution scope shard size set to 5:

Elixir

config :temporal_sdk,
  node: %{:scope_config => [{:cluster_1, 5}]},
  clusters: [
    cluster_1: [
      activities: [%{:task_queue => "default"}],
      workflows: [%{:task_queue => "default"}]
    ]
  ]

Erlang

{temporal_sdk, [
    {node, #{scope_config => [{cluster_1, 5}]}},
    {clusters, [
        {cluster_1, [
            {activities, [#{task_queue => "default"}]},
            {workflows, [#{task_queue => "default"}]}
            ]}
        ]}
]}

SDK Node Configuration

enable_single_distributed_workflow_execution - enables single workflow execution per Erlang cluster, see SDK Architecture - Workflow Execution Scope for details. Setting can be overwritten for each SDK cluster individually by using the SDK cluster configuration option with the same name, see m:temporal_sdk_cluster. Default: true.

scope_config - SDK node workflow execution scope configuration defined as a property list. Proplist key is the workflow_scope scope name set in the SDK cluster configuration and the proplist value is the given cluster scope shards count. If workflow_scope option is not set in the cluster configuration, the scope name will be the same as the cluster name. See SDK Architecture - Workflow Execution Scope section for details. Setting must be consistent across all Erlang cluster SDK nodes. By default, the shards count is set to 10 for each SDK cluster. Example: [{cluster_1, 20}].

limiter_time_windows - SDK node fixed window rate limiter time windows configuration. Values specified here also serve as the time intervals at which telemetry events [temporal_sdk, task_counter, node] are emitted. See m:temporal_sdk_limiter#module-concurrency-and-fixed-window-rate-limiters for details. By default, the fixed window rate limiter time window is set to 60 seconds:

Elixir

[
  activity_direct: 60_000,
  activity_eager: 60_000,
  activity_regular: 60_000,
  activity_session: 60_000,
  nexus: 60_000,
  workflow: 60_000
]

Erlang

[
  {activity_direct, 60_000},
  {activity_eager, 60_000},
  {activity_regular, 60_000},
  {activity_session, 60_000},
  {nexus, 60_000},
  {workflow, 60_000}
]

telemetry_poll_interval - the time interval at which the SDK node telemetry poller polls for SDK node statistics and emits [temporal_sdk, node, stats] telemetry event. Default poll time interval is 10 seconds.

telemetry_events_handlers - telemetry events handlers. See t:temporal_sdk_telemetry:events_handlers/0 for details. By default, all SDK telemetry events with the exception suffix are logged with the error log level using the built-in telemetry event handler function temporal_sdk_telemetry:handle_log/4:

[
    {
        fun() -> temporal_sdk_telemetry:events_by_suffix([exception]) end,
        fun temporal_sdk_telemetry:handle_log/4
    }
]