GraphQL client

This project is a GraphQL client for AEM. It is an OSGi bundle that can be instantiated with an OSGi configuration in the AEM OSGi configuration console. It can also be instantiated directly with java code.

Installation

To build and install the latest version in a running AEM instance, simply do

mvn clean install sling:install

This installs everything by default to localhost:4502 without any context path. You can also configure the install location with the following maven properties:

• aem.host: the name of the AEM instance
• aem.port: the port number of the AEM instance
• aem.contextPath: the context path (if any) of your AEM instance, starting with /

Using the GraphQL client

To use this library in your project, just add the following maven dependency to your project and install the bundle in your AEM instance:

<dependency>
    <groupId>com.adobe.commerce.cif</groupId>
    <artifactId>graphql-client</artifactId>
    <version>...</version>
    <scope>provided</scope>
</dependency>

You'll then have to setup and configure the client in your AEM instance.

OSGi configuration

To instantiate instances of this GraphQL client, simply go the AEM OSGi configuration console and look for "GraphQL Client Configuration Factory". Add a configuration and set the following mandatory parameters:

• identifier: must be unique among all GraphQL clients.
• url: the URL of the GraphQL server endpoint used by this client.
• httpMethod: the default HTTP method used to send requests, can be either GET or POST. This can be overriden on a request basis.

The identifier is used by the adapter factory to resolve clients via the cq:graphqlClient property set on any JCR node. When this is set on a resource or the resource ancestors, one can write GraphqlClient client = resource.adaptTo(GraphqlClient.class);.

Caching

Starting with version 1.4.0, the client can cache GraphQL query requests based on the cacheConfigurations parameter. This supports the configuration of multiple caches, each being identified by a name and having its own set of caching parameters. This ensures that multiple components and services using cached data can have their own caching strategy and that those will not collide, for example when one component/service starves a common cache with a very large amount of requests. On the Java side, caching is controlled by the CachingStrategy class that can be set in the RequestOptions class.

Because of the limitations of the AEM OSGi configuration console when defining multiple parameters with multiple values, each cache configuration entry must be specified with the following format:

• NAME:ENABLE:MAXSIZE:TIMEOUT like for example mycache:true:1000:60 where each attribute is defined as:
  • NAME (String) : the name of the cache
  • ENABLE (true|false) : enables or disables that cache entry (useful to temporarily disable a cache)
  • MAXSIZE (Integer) : the maximum size of the cache in number of entries
  • TIMEOUT (Integer) : the timeout for each cache entry, in seconds

Note that even if it is enabled, a cache is only used if the RequestOptions set by the caller component/service defines the cache name and explicitly sets the DataFetchingPolicy to CACHE_FIRST. This ensures that the behavior of the client is backwards compatible (= caching is skipped by default). In addition, a caller can explicitly set the DataFetchingPolicy to NETWORK_ONLY to skip caching programmatically, even if caching is enabled in the OSGi configuration.

Releases to Maven Central

Releases are triggered by manually running mvn release:prepare release:clean on the master branch. This automatically pushes a commit with a release git tag like graphql-client-x.y.z. which triggers a dedicated CircleCI build that performs the deployment of the artifact to Maven Central.

Code Formatting

You can find the code formatting rules in the eclipse-formatter.xml file. The code formatting is automatically checked for each build. To automatically format your code, please run:

mvn clean install -Pformat-code

Contributing

Contributions are welcomed! Read the Contributing Guide for more information.

Licensing

This project is licensed under the Apache V2 License. See LICENSE for more information.