Prerequisites and Limitations for Writing REST Applications
This topic describes prerequisites and limitations for writing VMware Tanzu GemFire REST applications.
Before development, you should understand the prerequisites and limitations of the Tanzu GemFire REST implementation.
Tanzu GemFire and REST-enabled applications accessing Tanzu GemFire are subject to the following rules and limitations:
- All domain objects, functions and function-arg classes must be properly configured and registered in the Tanzu GemFire deployment. Any functions that you wish to execute through the REST API must be available on the target member’s CLASSPATH.
- The current implementation supports only the application/json MIME type. Other return types (XML, objects, and so on) are not supported. Plain text is supported as a return type for some error messages.
- Keys are strictly of type String. For example, the request
PUT http://localhost:8080/gemfire-api/v1/customers/123.456will add an entry for key (“123.456”) of type String. - Some special formats of JSON documents are not supported in Tanzu GemFire REST. See Key Types and JSON Support for examples.
- To achieve interoperability between Tanzu GemFire Java clients (or Tanzu GemFire native clients) and REST clients, the following rules must be followed:
- All Tanzu GemFire Java and native client classes operating on data also accessed by the REST interface must be PDX serialized, either via PDX autoserialization or by implementing
PdxSerializable. - Tanzu GemFire Java clients and native clients can retrieve REST-enabled data either as a
PdxInstanceor as an actual object by using thePdxInstance.getObjectmethod. If you use the latter method, you must first declare the object type (@type) in your POST or PUT request payload when creating the object in REST; and secondly, the Java client must have the actual domain class in its CLASSPATH.
- All Tanzu GemFire Java and native client classes operating on data also accessed by the REST interface must be PDX serialized, either via PDX autoserialization or by implementing
- Objects returned by REST-invoked functions must be returned as PdxInstance objects or other data types that can be written to JSON. You cannot return Java objects.
- REST client applications do not support single hop access or notification features.
- Specifying subregions as endpoints is not supported.
