Rest.li with Servlet Containers

Contents

• Introduction
• Step 1. Creating a web.xml File
• Step 2. Building a War
• Jetty

Introduction

Rest.li may be run in a variety of http frameworks. Out of the box, Rest.li supports both Netty and Servlet containers, such as Jetty.

This describes how to run Rest.li one a servlet container by building a war containing a rest.li servlet. It also covers how to run Rest.li with Jetty.

Step 1. Creating a web.xml File

Rest.li provides a RestliServlet class to integrate rest.li into any Java servlet container.

To use RestliServlet, you will add a web.xml file.

For example, below is example-standalone-app/server/src/main/webapp/WEB-INF/web.xml, an extremely simple web.xml example that creates a RestliServlet and configures it to load all rest.li resources in the com.example.fortune.impl package.

Notice that RestliServlet automatically scans all resource classes in the specified package and initializes the REST endpoints/routes without any hard-coded connection. Adding additional resources or operations can be done simply by expanding your data schema and providing additional functionality in your Resource class(es).

file: example-standalone-app/server/src/main/webapp/WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC '-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN' 'http://java.sun.com/dtd/web-app_2_3.dtd'>

<web-app>
  <display-name>Fortunes App</display-name>
  <description>Tells fortunes</description>

  <!-- servlet definitions -->
  <servlet>
    <servlet-name>FortunesServlet</servlet-name>
    <servlet-class>com.linkedin.restli.server.RestliServlet</servlet-class>
      <init-param>
        <param-name>resourcePackages</param-name>
        <param-value>com.example.fortune.impl</param-value>
      </init-param>
      <load-on-startup>1</load-on-startup>
  </servlet>

  <!-- servlet mappings -->
  <servlet-mapping>
    <servlet-name>FortunesServlet</servlet-name>
    <url-pattern>/*</url-pattern>
  </servlet-mapping>

</web-app>

The parseq thread count (use to make outbound requests) may optionally be configured by setting the parSeqThreadPoolSize servlet init param, for example:

    <init-param>
      <param-name>parseqThreadPoolSize</param-name>
      <param-value>10</param-value>
    </init-param>

To configure jetty’s inbound request thread pool size, see Jetty’s documentation.

Step 2. Building a War

To build a war, we need a build.gradle file in the server directory, which should look like this:

file: example-standalone-app/server/build.gradle

apply plugin: 'war'
apply plugin: 'pegasus'

ext.apiProject = project(':api')

dependencies {
  compile project(path: ':api', configuration: 'dataTemplate')
  compile spec.product.pegasus.restliServer
}

For on the gradle ‘war’ plugin, see: Gradle War Plugin

Jetty

To run Rest.li on Jetty, use the war plugin like you would for any other servlet (above). For convenience, you can optionally setup a Gradle task to run your application in Jetty. Here’s an example:

file: example-standalone-app/server/build.gradle

apply plugin: 'war'
apply plugin: 'pegasus'

ext.apiProject = project(':api')

dependencies {
  compile project(path: ':api', configuration: 'dataTemplate')
  compile spec.product.pegasus.restliServer
}

configurations {
  jetty8
}

dependencies {
  jetty8 "org.mortbay.jetty:jetty-runner:8.1.15.v20140411" // set to whatever version of jetty you want to test with
}

task JettyRunWar(type: JavaExec) {
  main = "org.mortbay.jetty.runner.Runner"
  args = [war.archivePath]
  classpath configurations.jetty8
}

To start Rest.li on Jetty run:

gradle JettyRunWar

The server will start on port 8080 under the /server context path, for example:

curli http://localhost:8080/fortunes/1