Module vibe.web.rest

Endpoint generation

An endpoint is a combination of an HTTP method and a local URI. For each public method of the interface, one endpoint is registered in the URLRouter.

By default, the method and URI parts will be inferred from the method name by looking for a known prefix. For example, a method called getFoo will automatically be mapped to a 'GET /foo' request. The recognized prefixes are as follows:

Member functions that have no valid prefix default to 'POST'. Note that any of the methods defined in HTTPMethod are supported through manual endpoint specifications, as described in the next section.

After determining the HTTP method, the rest of the method's name is then treated as the local URI of the endpoint. It is expected to be in standard D camel case style and will be transformed into the style that is specified in the call to registerRestInterface, which defaults to MethodStyle.lowerUnderscored.

Manual endpoint specification

Endpoints can be controlled manually through the use of @path and @method annotations:

@path(

Manual path annotations also allows defining custom path placeholders that will be mapped to function parameters. Placeholders are path segments that start with a colon:

@path(

This will cause a request "GET /users/peter" to be mapped to the getUserByName method, with the _name parameter receiving the string "peter". Note that the matching parameter must have an underscore prefixed so that it can be distinguished from normal form/query parameters.

It is possible to partially rely on the default behavior and to only customize either the method or the path of the endpoint:

@method(HTTPMethod.POST)
void getFoo();

In the above case, as 'POST' is set explicitly, the route would be 'POST /foo'. On the other hand, if the declaration had been:

@path(

The route generated would be 'GET /bar'.

Properties

@property functions have a special mapping: property getters (no parameters and a non-void return value) are mapped as GET functions, and property setters (a single parameter) are mapped as PUT. No prefix recognition or trimming will be done for properties.

Method style

Method names will be translated to the given 'MethodStyle'. The default style is MethodStyle.lowerUnderscored, so that a function named getFooBar will match the route 'GET /foo_bar'. See MethodStyle for more information about the available styles.

Parameter passing

By default, parameter are passed via different methods depending on the type of request. For POST and PATCH requests, they are passed via the body as a JSON object, while for GET and PUT they are passed via the query string.

The default behavior can be overridden using one of the following annotations:

• @headerParam("name", "field"): Applied on a method, it will source the parameter named name from the request headers named "field". If the parameter is ref, it will also be set as a response header. Parameters declared as out will only be set as a response header.
• @queryParam("name", "field"): Applied on a method, it will source the parameter name from a field named "field" of the query string.
• @bodyParam("name", "field"): Applied on a method, it will source the parameter name from a field named "field" of the request body in JSON format.

@path(

Default values

Parameters with default values behave as optional parameters. If one is set in the interface declaration of a method, the client can omit a value for the corresponding field in the request and the default value is used instead.

Note that this can suffer from DMD bug #14369 (Vibe.d: #1043).

Aggregates

When passing aggregates as parameters, those are serialized differently depending on the way they are passed, which may be especially important when interfacing with an existing RESTful API:

• If the parameter is passed via the headers or the query, either implicitly or explicitly, the aggregate is serialized to JSON. If the JSON representation is a single string, the string value will be used verbatim. Otherwise the JSON representation will be used
• If the parameter is passed via the body, the datastructure is serialized to JSON and set as a field of the main JSON object that is expected in the request body. Its field name equals the parameter name, unless an explicit @bodyParam annotation is used.

See Also

To see how to implement the server side in detail, jump to registerRestInterface.

To see how to implement the client side in detail, jump to the RestInterfaceClient documentation.