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 page.
If you prefer to build Pravega yourself, you can download the code and run ./gradlew distribution
. More
details are shown in the Pravega README.md.
$ tar xfvz pravega-0.1.0.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 for Running Pravega are covered in the running Pravega guide.
$ cd pravega-0.1.0 $ bin/pravega-standalone
That's it. Pravega should be up and running very soon.
You can find additional ways to run Pravega in Running Pravega.
Running a sample Pravega App is simple too¶
Pravega maintains a separate github repository for sample applications. It is located at: https://github.com/pravega/pravega-samples
Lets download and run the "Hello World" Pravega sample reader and writer apps. Pravega dependencies will be pulled from maven central.
Note: The samples can also use a locally compiled version of Pravega. For more information about this see the note on maven publishing in the README.md.
Download the Pravega-Samples git repo
$ git clone https://github.com/pravega/pravega-samples $ cd pravega-samples
Generate the scripts to run the apps
$ ./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/standalone-examples/build/install/pravega-standalone-examples $ bin/helloWorldWriter
... Writing message: 'hello world' with routing-key: 'helloRoutingKey' to stream 'examples / helloStream' ...
Run the sample "HelloWorldReader"
$ cd pravega-samples/standalone-examples/build/install/pravega-standalone-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.md file in the standalone-examples for more details on running the HelloWorldReader application