Skip to content


Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
WRML, the Web Resource Modeling Language, is a domain-specific modeling language that's oriented toward the design of REST APIs.
Java JavaScript CSS CoffeeScript Other
branch: master


WRML, the Web Resource Modeling Language, is a domain-specific modeling language that's oriented toward the design of REST APIs. It is a formalization of common REST API design and implementation patterns found in modern application servers.

WRML is an open source software project ( focused on providing REST API standards, frameworks, and tools to support the development of web-oriented, client-server applications.

The initial implementation of the WRML runtime is Java-based, with the WrmlServlet providing the REST API engine that frees the service developer to focus on application logic.

Key Benefits

  • Loads and initializes REST API models (design metadata) to be routed and invoked

  • Routes requests to a configured “back-end” Service based upon the target API endpoint’s response document’s Schema

  • Generates hyperlinks in responses based upon the designs of the API and the response document’s Schema

  • Represents response documents using a configured Format (e.g. JSON)

  • To reduce the number of requests per screen, supports embedding linked document(s) within the requested document

  • To reduce the byte size of responses, supports omission of unused properties from the requested document

  • Exposes API and Schema metadata to automate generation of code and docs for clients and intermediaries

Getting Started

Getting started with WRML means something a little bit different to each role involved in the creation of REST APIs.

To those wanting to get started with the tools and find a link to download an installer (from an app store) or use a JS web app for REST API design - that documentation is still a work in progress.

The remainder of this README is intended for developers or other folks wanting to download, build, install, and run WRML.

Before you install WRML

From a console/terminal window, verify that Java 7 is installed:

$> java -version

Which should display something like this (with a "1.7.0" or higher version number):

java version "1.7.0"
Java(TM) SE Runtime Environment (build 1.7.0-b147)
Java HotSpot(TM) 64-Bit Server VM (build 21.0-b17, mixed mode)

If not, it can be downloaded from:

Also verify that Maven 3 is installed:

$>  mvn -version

Which should display something like this:

Apache Maven 3.0.5 (r01de14724cdef164cd33c7c8c2fe155faf9602da; 2013-02-19 05:51:28-0800)

If not, it can be downloaded from:

Download WRML

$> git clone

Install WRML

From the root directory (WRML_HOME) run maven's install command.

$> mvn install

Please note that the first time you run this command, it may download several of WRML's dependencies and install them into your system's local maven repository.

Configure WRML

Edit the WRML configuration file (wrml.json) to match your local environment. In the example below, these two lines are the important ones to match to your system:

File Service Root Directory

This setting specifies the root directory for WRML Models (stored as JSON files on disk).

"rootDirectory" : "E:/wrml/models/"

Schema Loader Schema Directory

This setting specifies the root directory for WRML Schemas (compiled as Java interfaces).

"schemaClassRootDirectory" : "E:/wrml/schemas"

For those having problems starting WRML, please confirm that the "slash" leaning direction of the folder/directory paths match the conventions of your OS. In java config files, the "/" forward slash should work cross-platform, but the java commands listed below contain path's like "..\core\target\core-1.0-SNAPSHOT.jar;" which are both Windows-centric (backslashes) and relative to the WRML_HOME/bin folder.

In lieu of an installer, please adjust config and script files according to match your environment.

WRML Tools

Werminal - WRML Model Editor

See the Werminal /cli project README.

For more about the Werminal app, please consult the "Werminal Masters Handbook":


See the /wrmldoc project.


WRML is copyright (C) 2012-2013 Mark Masse (OSS project WRML is licensed under the Apache License, Version 2.0. You may obtain a copy of the License at:

Something went wrong with that request. Please try again.