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---
layout: page
title: Getting Started with Samza REST
---
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This tutorial depends on [hello-samza](../../../startup/hello-samza/{{site.version}}/) to start some example jobs on a local cluster, which you will then access via the [JobsResource](../../documentation/{{site.version}}/rest/resources/jobs.html). After completing this tutorial, you will have built and deployed the Samza REST resource locally, changed the configuration for the JobsResource, and executed a couple of basic curl requests to verify the service works.
Lets get started.
### Run Hello Samza Jobs Locally
Follow the [hello-samza](../../../startup/hello-samza/{{site.version}}/) tutorial to setup a local grid and run the wikipedia jobs. Skip the [shutdown step](../../../startup/hello-samza/{{site.version}}/#shutdown) because you need the grid to still be running to query the REST service for jobs. You can optionally skip all the ```kafka-console-consumer.sh``` commands if you don't want to verify the output of the jobs.
Take note of the path where you cloned hello-samza. You will need this to configure the installations path for the JobsResource.
#### Build the Samza REST Service package
The source code for Samza REST is in the samza-rest module of the Samza repository. To build it, execute the following gradle task from the root of the project.
{% highlight bash %}
./gradlew samza-rest:clean releaseRestServiceTar
{% endhighlight %}
#### Deploy the Samza REST Service Locally
To deploy the service, you simply extract the tarball to the desired location. Here, we will deploy the tarball on the local host in
```
SAMZA_ROOT/samza-rest/build/distributions/deploy/samza-rest
```
where ```SAMZA_ROOT``` is the path to the root of your Samza project.
Run the following commands:
{% highlight bash %}
cd samza-rest/build/distributions/
mkdir -p deploy/samza-rest
tar -xvf ./samza-rest-0.14.0.tgz -C deploy/samza-rest
{% endhighlight %}
#### Configure the Installations Path
The JobsResource has a required config [job.installations.path](../../documentation/{{site.version}}/rest/resources/jobs.html#configuration) which specifies the path where the jobs are installed. Edit the configuration file:
```
deploy/samza-rest/config/samza-rest.properties
```
Set the job.installations.path to:
```
job.installations.path=/hello-samza-ROOT/deploy
```
where ```hello-samza-ROOT``` is the path to your hello-samza clone, noted above. This tells the JobsResource to crawl this location to find all the installed jobs.
#### Start the Samza REST Service
To deploy the service, run the run-samza-rest-service.sh script from the extracted directory.
{% highlight bash %}
cd deploy/samza-rest
./bin/run-samza-rest-service.sh \
--config-factory=org.apache.samza.config.factories.PropertiesConfigFactory \
--config-path=file://$PWD/config/samza-rest.properties
{% endhighlight %}
You provide two parameters to the run-samza-rest-service.sh script. One is the config location, and the other, optional, parameter is a factory class that is used to read your configuration file. The SamzaRestService uses your ConfigFactory to get a Config object from the config path. The ConfigFactory is covered in more detail on the [Job Runner page](../../documentation/{{site.version}}/jobs/job-runner.html). The run-samza-rest-service.sh script will block until the SamzaRestService terminates.
Note: With the default settings, the JobsResource will expect a YARN cluster with a local Resource Manager accessible via the ApplicationCLI. Without YARN, the JobsResource will not respond to any requests. So it's important to walk through hello-samza demo before the next step.
### Curl the Default REST Service
Curl the JobsResource to get all installed jobs
```
curl localhost:9139/v1/jobs
[{"jobName":"wikipedia-stats","jobId":"1","status":"STARTED","statusDetail":RUNNING},{"jobName":"wikipedia-parser","jobId":"1","status":"STARTED","statusDetail":RUNNING},{"jobName":"wikipedia-feed","jobId":"1","status":"STARTED","statusDetail":RUNNING}
```
Now curl the JobsResource to stop one of the jobs
```
curl -X PUT localhost:9139/v1/jobs/wikipedia-feed/1?status=stopped
{"jobId":"1","jobName":"wikipedia-feed","status":"STOPPED","statusDetail":"FINISHED"}
```
Congratulations, you've successfully deployed the Samza REST Service and used the JobsResource to list jobs and stop a job!
See the [JobsResource documentation](../../documentation/{{site.version}}/rest/resources/jobs.html) for the rest of its API.
See the [Resources documentation](../../documentation/{{site.version}}/rest/resources.html) for more information about Resources and how you can add your own.