CommandableHttpClient

Implements: RestClient

Description

The CommandableHttpClient class allows you to create commandable services. Commandable services are generated automatically for ICommandable objects.

Important points

• Each command is exposed as a POST operation that receives all parameters in the body object.

Configuration parameters

• base_route: base route for a remote URI
• connection(s):
  • discovery_key: (optional) key to retrieve the connection from IDiscovery
  • protocol: connection protocol (http or https)
  • host: host name or IP address
  • port: port number
  • uri: resource URI or connection string with all parameters in it
• options:
  • retries: number of retries (default: 3)
  • connect_timeout: connection timeout in milliseconds (default: 10 sec)
  • timeout: invocation timeout in milliseconds (default: 10 sec)

References

• *:logger:*:*:1.0 - (optional) ILogger components to pass log messages
• *:counters:*:*:1.0 - (optional) ICounters components to pass collected measurements
• *:traces:*:*:1.0 - (optional) ITracer components to record traces
• *:discovery:*:*:1.0 - (optional) IDiscovery services to resolve a connection

Constructors

Creates a new instance of the client.

CommandableHttpClient(base_route: str)

• base_route: str - base route for a remote service.

Instance methods

call_command

Calls a remote method via the HTTP commadable protocol. The call is made via a POST operation and all parameters are sent in the body object. The complete route to the remote method is defined as baseRoute + “/” + name.

call_command(name: str, correlation_id: Optional[str], params: Any): Any

• name: str - name of the command to call.
• correlation_id: Optional[str] - (optional) transaction id used to trace execution through a call chain.
• params: Any - command parameters.
• returns: Any - result of the command.

Examples

class MyCommandableHttpClient(CommandableHttpClient, IMyClient):
    # ...

    def get_data(self, correlation_id, id):
        return self.call_command("get_data", correlation_id, MyData(id))

        # ...

    client = MyCommandableHttpClient()
    client.configure(ConfigParams.from_tuples("connection.protocol", "http",
                                                 "connection.host", "localhost",
                                                 "connection.port", 8080))
                                                 
    client.open("123")
    
    data = client.getData("123", "1")
     # ...