SMD: Service Mapping Description
SMD stands for Service Mapping Description, a JSON schema that defines how a client can interact with a particular web service. At the time of this writing, the specification has not yet been formally ratified, but it is in use already within Dojo Toolkit as well as other JSON-RPC consumer clients.
At its most basic, a Service Mapping Description indicates the method of
GET, TCP/IP, etc), the request envelope type (usually
based on the protocol of the server), the target URL of the service provider,
and a map of services available. In the case of JSON-RPC, the service map is a
list of available methods, which each method documenting the available
parameters and their types, as well as the expected return value type.
Zend\Json\Server\Smd provides an object-oriented way to build service maps.
At its most basic, you pass it metadata describing the service using mutators,
and specify services (methods and functions).
The service descriptions themselves are typically instances of
Zend\Json\Server\Smd\Service; you can also pass all information as an array
to the various service mutators in
Zend\Json\Server\Smd, and it will
instantiate a service for you. The service objects contain information such as
the name of the service (typically the function or method name), the parameters
(names, types, and position), and the return value type. Optionally, each
service can have its own target and envelope, though this functionality is
Zend\Json\Server\Server actually does all of this behind the scenes for you,
by using reflection on the attached classes and functions; you should create
your own service maps only if you need to provide custom functionality that
class and function introspection cannot offer.
Methods available in
setOptions(array $options): Setup an SMD object from an array of options. All mutators (methods beginning with 'set') can be used as keys.
setTransport($transport): Set the transport used to access the service; only POST is currently supported.
getTransport(): Get the current service transport.
setEnvelope($envelopeType): Set the request envelope that should be used to access the service. Currently, supports the constants
getEnvelope(): Get the current request envelope.
setContentType($type): Set the content type requests should use (by default, this is 'application/json').
getContentType(): Get the current content type for requests to the service.
setTarget($target): Set the URL endpoint for the service.
getTarget(): Get the URL endpoint for the service.
setId($id): Typically, this is the URL endpoint of the service (same as the target).
getId(): Retrieve the service ID (typically the URL endpoint of the service).
setDescription($description): Set a service description (typically narrative information describing the purpose of the service).
getDescription(): Get the service description.
setDojoCompatible($flag): Set a flag indicating whether or not the SMD is compatible with Dojo toolkit. When
TRUE, the generated JSON SMD will be formatted to comply with the format that Dojo's JSON-RPC client expects.
isDojoCompatible(): Returns the value of the Dojo compatibility flag (
FALSE, by default).
addService($service): Add a service to the map. May be an array of information to pass to the constructor of
Zend\Json\Server\Smd\Service, or an instance of that class.
addServices(array $services): Add multiple services at once.
setServices(array $services): Add multiple services at once, overwriting any previously set services.
getService($name): Get a service by its name.
getServices(): Get all attached services.
removeService($name): Remove a service from the map.
toArray(): Cast the service map to an array.
toDojoArray(): Cast the service map to an array compatible with Dojo Toolkit.
toJson(): Cast the service map to a JSON representation.
Zend\Json\Server\Smd\Service has the following methods:
setOptions(array $options): Set object state from an array. Any mutator (methods beginning with 'set') may be used as a key and set via this method.
setName($name): Set the service name (typically, the function or method name).
getName(): Retrieve the service name.
setTransport($transport): Set the service transport (currently, only transports supported by
getTransport(): Retrieve the current transport.
setTarget($target): Set the URL endpoint of the service (typically, this will be the same as the overall SMD to which the service is attached).
getTarget(): Get the URL endpoint of the service.
setEnvelope($envelopeType): Set the service envelope (currently, only envelopes supported by
getEnvelope(): Retrieve the service envelope type.
addParam($type, array $options = array(), $order = null): Add a parameter to the service. By default, only the parameter type is necessary. However, you may also specify the order, as well as options such as:
- name: the parameter name
- optional: whether or not the parameter is optional
- default: a default value for the parameter
- description: text describing the parameter
addParams(array $params): Add several parameters at once; each param should be an assoc array containing minimally the key 'type' describing the parameter type, and optionally the key 'order'; any other keys will be passed as
setParams(array $params): Set many parameters at once, overwriting any existing parameters.
getParams(): Retrieve all currently set parameters.
setReturn($type): Set the return value type of the service.
getReturn(): Get the return value type of the service.
toArray(): Cast the service to an array.
toJson(): Cast the service to a JSON representation.