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Getting Started¶

The best way to get to know Pravega is to start it up and run a sample Pravega application.

Running Pravega is Simple¶

Verify the following prerequisite

Java 8

Download Pravega

Download the Pravega release from the Github Releases. If you prefer to build Pravega yourself, you can download the code and run ./gradlew distribution. More details are shown in the Pravega README.

$ tar xfvz pravega-<version>.tgz

Run Pravega in standalone mode

This launches all the components of Pravega on your local machine.

Note: This is for testing/demo purposes only, do not use this mode of deployment in Production!

More options and additional ways to run Pravega can be found in Running Pravega guide.

$ cd pravega-<version>
$ bin/pravega-standalone

The command above runs Pravega locally for development and testing purposes. It does not persist in the storage tiers like we do with a real deployment of Pravega and as such you shouldn't expect it to recover from crashes, and further, not rely on it for production use. For production use, we strongly encourage a full deployment of Pravega.

Running a sample Pravega Application¶

We have developed a few samples to introduce the developer to coding with Pravega here: Pravega Samples.

Download and run the "Hello World" Pravega sample reader and writer applications. Pravega dependencies will be pulled from maven central.

Note: The samples can also use a locally compiled version of Pravega. For more information, please see the README note on maven publishing.

Download the Pravega-Samples git repo

$ git clone https://github.com/pravega/pravega-samples
$ cd pravega-samples

Generate the scripts to run the applications

$ ./gradlew installDist

Run the sample "HelloWorldWriter"

This runs a simple Java application that writes a "hello world" message as an event into a Pravega stream.

$ cd pravega-samples/pravega-client-examples/build/install/pravega-client-examples
$ bin/helloWorldWriter

Example HelloWorldWriter output

...
Writing message: 'hello world' with routing-key: 'helloRoutingKey' to stream 'examples / helloStream'
...

See the README file in the standalone-examples for more details on running the HelloWorldWriter with different parameters.

Run the sample "HelloWorldReader"

$ cd pravega-samples/pravega-client-examples/build/install/pravega-client-examples
$ bin/helloWorldReader

Example HelloWorldReader output

...
Reading all the events from examples/helloStream
...
Read event 'hello world'
No more events from examples/helloStream
...

See the README file in the pravega-client-examples for more details on running the HelloWorldReader application.