Anypoint Connector DevKit
The MuleSoft Anypoint™ Connector DevKit provides the following features to help you develop or maintain a connector:
Visual design and implementation using Anypoint Studio with an Eclipse-oriented interface that helps simplify and speed up development
Maven support for development and building
Connector development and packaging tools
Authentication support for multiple types of authentication like OAuth and Basic Authentication
DataSense support to acquire metadata from endpoints
Extensive testing capability
Examples, training, and support to simplify startup and solve issues
Provides Batch, query pagination, and DataSense Query Language support
Note: For version 3.6 migration information, see Connector Migration Guide Mule 3.5 to 3.6.
Want to try a tutorial? See Tutorial - Barn Connector
What's a Connector?
A connector is software that provides a connection between a Mule flow and an external resource. The resource can be any source of content, such as a database, protocol, or API. You can create a connector with the Anypoint Connector DevKit and the Anypoint Studio IDE. A connector is written in Java version 7. Connectors access web resources using REST, SOAP, or the Java SDK.
Anypoint Connector DevKit provides the tools and interfaces for building custom connectors. As reusable components that hide API complexity from the integration developer, custom connectors facilitate integration with SaaS and on-premise Web services, applications, and data sources. Connectors that you build using Anypoint DevKit in Anypoint Studio and in Mule ESB runtime environments, function as extensions of the core product.
The following is an example connector that Anypoint Studio creates for you as a starting point:
From this example, you can see a connector starts with the @Connector annotation, and that annotations define functionality, processing, and connection strategy. From this starting point, you add classes that let you access the interface of the resource to which you connect, to process the data, write tests, document your connector, and publish it so that the connector is accessible from Studio.
- Before creating a connector, explore the MuleSoft connectors to see if one meets your needs.
- Download and install Java version 7 and Apache Maven.
- Get access to a sandbox environment for testing your connector with the target resource before taking your connector into production.
- Understand Java annotations.
Connectors operate within MuleSoft flows:
A connector has two sides. The Mule-facing side communicates with a resource’s target-facing client side to enable content to travel between the Mule flow and the resource.
From the Mule-facing side, a connector consists of:
A main Java class. Java code that you annotate with the @Connector attribute.
Connector attributes. Properties of the @Connector class that you annotate with the @Configurable attribute. See Java annotations for information on how annotations work. See the Annotation Reference for information about Anypoint Connector DevKit annotations.
Methods. Functionality that you annotate with the @Processor attribute.
Additional annotations define authentication-related functionality and connection management, and to control the layout of the Anypoint Studio dialogues for the connector. The data model and exceptions that either raise or propagate are also Mule-facing classes.
Anypoint DevKit generates a skeleton connector when you create your Anypoint Connector project in Studio. The skeleton connector includes the @Connector class, the @Configurable attributes, the @Processor methods, and authentication logic to build out your connector. During the build process, the annotation processor extends your code with functionality to integrate with Mule.
The target facing or client facing side of a connector depends on the client technology that enables access to the resource. This functionality consists of a class library and one or more classes that Mule-facing @Connector class uses to access client functionality. This functionality is called the client class.
The client class in turn generally depends on other classes to actually implement calls to the target. Depending on your target, some of these classes may be generated or provided for you. For example, if you have a Java client library, or are working with a SOAP or REST service, most of the client code is implemented there. In other cases, you have to write this code yourself.
Anypoint Connector DevKit lets you build connectors that don't exist. Before creating a connector, check Connectors for available connectors. The Connectors page also lists Community open source connectors that let you contribute to the growing community of public connector development.
Connector Data Model
The data model for the connector consists of the objects passed into and out of the exposed operations. While many Web services accept and return XML or JSON data, a proper Mule connector must translate the data format the client uses into Java objects – either POJOs or key-value maps which represent the data objects sent to, and returned from, the target. (Returning raw XML or JSON responses to Mule is one marker for an immature, improperly implemented connector.)
REST Versus SOAP
REST simplifies access to HTTP using POST, GET, PUT, and DELETE calls to provide access to creating, getting, putting, and deleting information on a resource.
DevKit provides a set of annotations called @RestCall annotations that helps building a Connector for a RESTful API.
SOAP is a traditional means of communicating with a resource and requires a WSDL file, which is an XML file that specifies all aspects of a Java class’s structure, methods, properties, and documentation. SOAP is an industry standard with tools for governance, building, and schema information.
DevKit provides a tools that helps building a connector using a WSDL file.
Creating a Connector
To create a connector:
Set up your development environment - Install Java JDK version 7, Apache Maven, and Anypoint Studio to build and test your connector. You can develop a connector using Windows, Mac, or Linux.
New Connector - Create an Anypoint project - Set up Anypoint Studio and install the connector plugin.
Existing Connector - To import an existing connector project, click File > Import > Anypoint Studio > Anypoint Connector Project from External Location, choose a URL or a .zip file, and complete the wizard to locate and import the project.
Determine resource access - Each resource has a different access method, such as REST, SOAP, FTP, or the Java SDK features.
Choose an authentication mechanism - Mule supports OAuth V1 or V2, basic authentication using a username and password, or basic using authentication protocols such as API Key, SAML, NTLM, Kerberos, or LDAP.
Add connector @ attribute annotations - Create code for your connector containing the @ attributes that Mule uses to designate the important parts of your connector.
Code tests - Tests can be unit tests, functional tests, and Studio interoperability tests.
Document your connector - MuleSoft provides a template that helps you fill in the blanks to create documentation to help your staff and to help others understand the features and use of your connector.
Anypoint Connector DevKit Features
Anypoint Connector DevKit supports:
Connector Development Lifecycle
|Connector Development||Provides steps to follow from set up to packaging a connector.|
|Anypoint Connectors||How to use and implement connectors - this section is in the Mule User Guide.|
|Connectors||Connectors available from MuleSoft or third party sources.|
|DataSense-Enabled Connectors||View which MuleSoft connectors support DataSense.|
|Annotations Reference||Describes DevKit elements that start with an at sign(@), which you can use in your connector to identify classes and functions for Anypoint functionality.|