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Standalone Activities Feature Guide

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Standalone Activities are Activities that run independently, without being orchestrated by a Workflow. Instead of starting an Activity from within a Workflow Definition, you start a Standalone Activity directly from a Temporal Client using ActivityClient.

The way you write the Activity and register it with a Worker is identical to Workflow Activities. The only difference is that you execute a Standalone Activity directly from your Temporal Client.

tip

New to Standalone Activities? Start with the Standalone Activities Quickstart.

This page covers the following:

info

This documentation uses source code from the standaloneactivities sample.

Start a Standalone Activity without waiting for the result​

Starting a Standalone Activity means sending a request to the Temporal Server to durably enqueue your Activity job, without waiting for it to be executed by your Worker.

Use ActivityClient.start() to start a Standalone Activity and get a handle without waiting for the result:

StartActivity.java

ActivityHandle<String> handle =
    client.start(
        GreetingActivities.class,
        GreetingActivities::composeGreeting,
        options,
        "Hello",
        "World");
System.out.println("Started activity ID: " + ACTIVITY_ID);

// Wait for the result later
String result = handle.getResult();
System.out.println("Activity result: " + result);

With the Temporal Server and Worker running, open a new terminal in the samples-java directory and run:

./gradlew -q execute -PmainClass=io.temporal.samples.standaloneactivities.StartActivity

Or use the Temporal CLI:

./temporal activity start \
  --type ComposeGreeting \
  --activity-id standalone-activity-id \
  --task-queue standalone-activity-task-queue \
  --start-to-close-timeout 10s \
  --input '"Hello"' \
  --input '"World"'

Get a handle to an existing Standalone Activity​

Use client.getHandle() to create a typed handle to a previously started Standalone Activity:

ActivityHandle<String> handle =
    client.getHandle("standalone-activity-id", null, String.class);

Pass null as the run ID to target the latest run of the given activity ID. You can then use the handle to wait for the result, describe, cancel, or terminate the Activity.

Wait for the result of a Standalone Activity​

Under the hood, calling client.execute() is the same as calling client.start() to durably enqueue the Standalone Activity, and then calling handle.getResult() to block until the Activity completes and return the result:

String result = handle.getResult();

To wait asynchronously without blocking the calling thread, use handle.getResultAsync(), which returns a CompletableFuture<R>:

CompletableFuture<String> future = handle.getResultAsync();

Or use the Temporal CLI to wait for a result by Activity ID:

./temporal activity result --activity-id standalone-activity-id

List Standalone Activities​

Use client.listExecutions() to list Standalone Activity Executions that match a List Filter query. The result is a Stream<ActivityExecutionMetadata> that fetches pages from the server on demand as the stream is consumed.

These APIs return only Standalone Activity Executions. Activities running inside Workflows are not included.

ListActivities.java

client
    .listExecutions("TaskQueue = '" + TASK_QUEUE + "'")
    .forEach(
        info ->
            System.out.printf(
                "ActivityID: %s, Type: %s, Status: %s%n",
                info.getActivityId(), info.getActivityType(), info.getStatus()));

Run it:

./gradlew -q execute -PmainClass=io.temporal.samples.standaloneactivities.ListActivities

Or use the Temporal CLI:

./temporal activity list

The query parameter accepts the same List Filter syntax used for Workflow Visibility. For example, ActivityType = 'composeGreeting' AND Status = 'Running'.

Count Standalone Activities​

Use client.countExecutions() to count Standalone Activity Executions that match a List Filter query. This returns the total count of executions (running, completed, failed, etc.) — not the number of queued tasks. It works the same way as counting Workflow Executions.

CountActivities.java

ActivityExecutionCount resp = client.countExecutions("TaskQueue = '" + TASK_QUEUE + "'");
System.out.println("Total activities: " + resp.getCount());
resp.getGroups()
    .forEach(
        group ->
            System.out.println("Group " + group.getGroupValues() + ": " + group.getCount()));

Run it:

./gradlew -q execute -PmainClass=io.temporal.samples.standaloneactivities.CountActivities

Or use the Temporal CLI:

./temporal activity count

Run Standalone Activities with Temporal Cloud​

The Worker and Client code in the Standalone Activities Quickstart use ClientConfigProfile.load(), so the same code works against Temporal Cloud — configure the connection via environment variables or a TOML profile. No code changes are needed.

For a step-by-step guide on connecting to Temporal Cloud, including Namespace creation, certificate generation, and authentication setup in the Cloud UI, see Connect to Temporal Cloud.

Connect with mTLS​

Set these environment variables with values from your Temporal Cloud Namespace settings:

export TEMPORAL_ADDRESS=<your-namespace>.<your-account-id>.tmprl.cloud:7233
export TEMPORAL_NAMESPACE=<your-namespace>.<your-account-id>
export TEMPORAL_TLS_CLIENT_CERT_PATH='path/to/your/client.pem'
export TEMPORAL_TLS_CLIENT_KEY_PATH='path/to/your/client.key'

Connect with an API key​

Set these environment variables with values from your Temporal Cloud API key settings:

export TEMPORAL_ADDRESS=<your-namespace>.<your-account-id>.tmprl.cloud:7233
export TEMPORAL_NAMESPACE=<your-namespace>.<your-account-id>
export TEMPORAL_API_KEY=<your-api-key>

Then run the Worker and starter code as shown in the Standalone Activities Quickstart.