Using the Plug-in SDK

Datameer is customizable using the Datameer SDK and public API to create plug-ins. Types of plug-ins currently available include functions, file types, export formats, and connections. Additional plug-in types will be supported in the future.

Prerequisites

• Java 7 JDK
• Ant 1.7 or newer
• Cygwin DLL (for developers using Windows)
• If you are installing a plug-in that uses extension points, make sure to install the plug-in that supplies those extension points first.

Extension Points

Extension points are the sockets where plug-in developers can plug-in their extensions. Currently there are a number of extension points available:

Extensions

Extensions can be added for the available extension points. Every plug-in can contribute an arbitrary number of extensions to the Datameer system.

Development

Plug-ins can be developed using the plug-in SDK that is included in the Datameer release. When you have installed Datameer you will find the plug-in SDK in the following location where <version> is the version of Datameer you are using:

plugin-sdk-<version>.zip

Installing the Datameer SDK

To install the SDK, copy the zip file to your development machine and install it to the location of your choice using the following commands:

cd <destination>
unzip /<path>/plugin-sdk-<version>.zip
export DAS_PLUGIN_SDK_HOME=<path>

You are now ready to develop your first plug-in.

Creating a Plug-in

To create a plug-in

1. Run the provided script to create a new plug-in project:

   $DAS_PLUGIN_SDK_HOME/bin/create-das-plugin.sh <project target dir>
   

   For example:

   $DAS_PLUGIN_SDK_HOME/bin/create-das-plugin.sh ~/development/das/my-first-plugin
   

   This creates a plug-in project under ~/development/das/my-first-plugin

2. Change directories to the newly created project:

   cd ~/development/das/my-first-plugin
   

3. Create Eclipse project files:

   ant eclipse
   

4. Import the plug-in project to Eclipse using File > Import ... > Existing Projects into Workspace > select the project directory.
5. You are now ready to start developing Datameer extensions.

Define a New Extension Point Within a Plug-in

1. In the plugin.xml, add the name of the extension point you want to add. 

   For example:

   <?xml version="1.0" encoding="UTF-8"?>
   <plugin
      id="plugin-example"
      name="Example Plugin with Extension Point"
      version="${datameer.version}"
      provider-name="Datameer, Inc.">
   
      <requires>
         <import plugin="das.sdk"/>
      </requires>
   
      <extension-point id="datameer.plugin.example.ExampleExtensionPoint" name="Example Extension Point" />
   </plugin>

   Open your extension point and define your methods.
   For example:

   package datameer.plugin.example;
   
   import datameer.com.google.common.annotations.Beta;
   import datameer.dap.sdk.plugin.SingletonExtension;
   
   public abstract class ExampleExtensionPoint implements SingletonExtension {
   
       public static final String EXTENSION_POINT_NAME = ExampleExtensionPoint.class.getName();
   
       @Override
       public final String getExtensionPoint() {
           return EXTENSION_POINT_NAME;
       }
     
       /**
      Add your extension point specific methods here
      **/
       public abstract Sting foo();
   
   }

Documentation

The Javadoc of the Datameer SDK is available. 

$DAS_PLUGIN_SDK_HOME/doc/index.html 

Writing Extensions

See the following tutorials:

• Tutorial01 - Building an Input Adaptor for Custom File Types
• Tutorial02 - Building Custom Functions
• Tutorial04 - Building a Custom Authenticator
• Tutorial05 - Building an Import Adaptor for Custom Connections
• Tutorial06 - Building an Export Adaptor for Custom Connections

Plug-in File Format

Datameer plug-ins are zip files of the following structure:

Versioning

Edit the files plugin.xml and build.properties to assign the appropriate names and version numbers before the plug-in is built.

Datameer will show the name in the UI which is used in the name tag. 

<plugin
   id="plugin-name"
   name="Plugin Name"
   version="<SDK-version>-<plugin-version>"
   provider-name="MyCompany">
...

The plug-in file name is built from the name and version tag. 

sdk.home=<path-to-SDK>
version=<SDK-version>-<plugin-version>
...

Installing and Testing a Plug-in

1. Bundle your plug-in as zip file:

   ant zip
   

2. In Datameer, go to the Admin Tab > Plug-ins page.
3. At the bottom of the page under Upload Plug-ins heading, click Choose File.
4. Select the file and click Upload.