Manage Functions
Pulsar Functions are lightweight compute processes that
- consume messages from one or more Pulsar topics
- apply a user-supplied processing logic to each message
- publish the results of the computation to another topic
Functions can be managed via the following methods.
| Method | Description |
|---|---|
| Admin CLI | The functions command of the pulsar-admin tool. |
| REST API | The /admin/v3/functions endpoint of the admin REST API. |
| Java Admin API | The functions method of the PulsarAdmin object in the Java API. |
Function resources#
You can perform the following operations on functions.
Create a function#
You can create a Pulsar function in cluster mode (deploy it on a Pulsar cluster) using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the create subcommand.
Example
$ pulsar-admin functions create \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --inputs test-input-topic \ --output persistent://public/default/test-output-topic \ --classname org.apache.pulsar.functions.api.examples.ExclamationFunction \ --jar /examples/api-examples.jar
FunctionConfig functionConfig = new FunctionConfig();functionConfig.setTenant(tenant);functionConfig.setNamespace(namespace);functionConfig.setName(functionName);functionConfig.setRuntime(FunctionConfig.Runtime.JAVA);functionConfig.setParallelism(1);functionConfig.setClassName("org.apache.pulsar.functions.api.examples.ExclamationFunction");functionConfig.setProcessingGuarantees(FunctionConfig.ProcessingGuarantees.ATLEAST_ONCE);functionConfig.setTopicsPattern(sourceTopicPattern);functionConfig.setSubName(subscriptionName);functionConfig.setAutoAck(true);functionConfig.setOutput(sinkTopic);admin.functions().createFunction(functionConfig, fileName);
Update a function#
You can update a Pulsar function that has been deployed to a Pulsar cluster using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST Admin API
- Java Admin API
Use the update subcommand.
Example
$ pulsar-admin functions update \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --output persistent://public/default/update-output-topic \ # other options
FunctionConfig functionConfig = new FunctionConfig();functionConfig.setTenant(tenant);functionConfig.setNamespace(namespace);functionConfig.setName(functionName);functionConfig.setRuntime(FunctionConfig.Runtime.JAVA);functionConfig.setParallelism(1);functionConfig.setClassName("org.apache.pulsar.functions.api.examples.ExclamationFunction");UpdateOptions updateOptions = new UpdateOptions();updateOptions.setUpdateAuthData(updateAuthData);admin.functions().updateFunction(functionConfig, userCodeFile, updateOptions);
Start an instance of a function#
You can start a stopped function instance with instance-id using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the start subcommand.
$ pulsar-admin functions start \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --instance-id 1
admin.functions().startFunction(tenant, namespace, functionName, Integer.parseInt(instanceId));
Start all instances of a function#
You can start all stopped function instances using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java
Use the start subcommand.
Example
$ pulsar-admin functions start \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \
admin.functions().startFunction(tenant, namespace, functionName);
Stop an instance of a function#
You can stop a function instance with instance-id using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the stop subcommand.
Example
$ pulsar-admin functions stop \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --instance-id 1
admin.functions().stopFunction(tenant, namespace, functionName, Integer.parseInt(instanceId));
Stop all instances of a function#
You can stop all function instances using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the stop subcommand.
Example
$ pulsar-admin functions stop \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \
admin.functions().stopFunction(tenant, namespace, functionName);
Restart an instance of a function#
Restart a function instance with instance-id using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the restart subcommand.
Example
$ pulsar-admin functions restart \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --instance-id 1
admin.functions().restartFunction(tenant, namespace, functionName, Integer.parseInt(instanceId));
Restart all instances of a function#
You can restart all function instances using Admin CLI, REST API or Java admin API.
- Admin CLI
- REST API
- Java Admin API
Use the restart subcommand.
Example
$ pulsar-admin functions restart \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \
admin.functions().restartFunction(tenant, namespace, functionName);
List all functions#
You can list all Pulsar functions running under a specific tenant and namespace using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the list subcommand.
Example
$ pulsar-admin functions list \ --tenant public \ --namespace default
admin.functions().getFunctions(tenant, namespace);
Delete a function#
You can delete a Pulsar function that is running on a Pulsar cluster using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the delete subcommand.
Example
$ pulsar-admin functions delete \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions)
admin.functions().deleteFunction(tenant, namespace, functionName);
Get info about a function#
You can get information about a Pulsar function currently running in cluster mode using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the get subcommand.
Example
$ pulsar-admin functions get \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions)
admin.functions().getFunction(tenant, namespace, functionName);
Get status of an instance of a function#
You can get the current status of a Pulsar function instance with instance-id using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the status subcommand.
Example
$ pulsar-admin functions status \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --instance-id 1
admin.functions().getFunctionStatus(tenant, namespace, functionName, Integer.parseInt(instanceId));
Get status of all instances of a function#
You can get the current status of a Pulsar function instance using Admin CLI, REST API or Java Admin API.
- Admin CLI
- REST API
- Java Admin API
Use the status subcommand.
Example
$ pulsar-admin functions status \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions)
admin.functions().getFunctionStatus(tenant, namespace, functionName);
Get stats of an instance of a function#
You can get the current stats of a Pulsar Function instance with instance-id using Admin CLI, REST API or Java admin API.
- Admin CLI
- REST API
- Java Admin API
Use the stats subcommand.
Example
$ pulsar-admin functions stats \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --instance-id 1
admin.functions().getFunctionStats(tenant, namespace, functionName, Integer.parseInt(instanceId));
Get stats of all instances of a function#
You can get the current stats of a Pulsar function using Admin CLI, REST API or Java admin API.
- Admin CLI
- REST API
- Java Admin API
Use the stats subcommand.
Example
$ pulsar-admin functions stats \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions)
admin.functions().getFunctionStats(tenant, namespace, functionName);
Trigger a function#
You can trigger a specified Pulsar function with a supplied value using Admin CLI, REST API or Java admin API.
- Admin CLI
- REST API
- Java Admin API
Use the trigger subcommand.
Example
$ pulsar-admin functions trigger \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --topic (the name of input topic) \ --trigger-value \"hello pulsar\" # or --trigger-file (the path of trigger file)
admin.functions().triggerFunction(tenant, namespace, functionName, topic, triggerValue, triggerFile);
Put state associated with a function#
You can put the state associated with a Pulsar function using Admin CLI, REST API or Java admin API.
- Admin CLI
- REST API
- Java Admin API
Use the putstate subcommand.
Example
$ pulsar-admin functions putstate \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --state "{\"key\":\"pulsar\", \"stringValue\":\"hello pulsar\"}"
POST /admin/v3/functions/:tenant/:namespace/:functionName/state/:key?version=@pulsar:version_number@
TypeReference<FunctionState> typeRef = new TypeReference<FunctionState>() {};FunctionState stateRepr = ObjectMapperFactory.getThreadLocal().readValue(state, typeRef);admin.functions().putFunctionState(tenant, namespace, functionName, stateRepr);
Fetch state associated with a function#
You can fetch the current state associated with a Pulsar function using Admin CLI, REST API or Java admin API.
- Admin CLI
- REST API
- Java Admin CLI
Use the querystate subcommand.
Example
$ pulsar-admin functions querystate \ --tenant public \ --namespace default \ --name (the name of Pulsar Functions) \ --key (the key of state)
admin.functions().getFunctionState(tenant, namespace, functionName, key);