* Delete response_topic_prefix
The Response-Infomation in CONNACK was misinterpreated, it should
not be a broker's global config, instead, it should be per-client
or even per-session prefix/suffix mechanism
* Delete request-response code from emqx_client
* Add request-response test code
* meck as default dependency --- temp workaround for dep-vsn-check
* Fix issue#1874
Prior to this change, if user use one client connect emqx with mqtt
v3.1.1, the client subscribe the topic and publish message to this
topic, it would receive this message itself published, this commit
provide a configure option to let user ignore the message itself published.
This change fix issue 1874.
* Small Fix
* Fix bug
* Better design
* Fix compile warning and improve coverage
* Better design to solve the performance issue
* Fix typo
* Fix typo
* Delete spaces in end of lines.
* Do not use anonymous function
* Better performance
Prior to this change, emqx_client:start_link does 2 works in one call:
- init an erlang process for emqx_client
- send MQTT CONNECT to remote broker
But this solution have some drawbacks:
- the return value of `start_link` compiles the return values of the 2
works: {ok, Pid, MqttResult}. It is inconsistent with the return value
of `gen_statem:start_link`, may causes confusions.
- the return mode of the 2 works are different:
`start_link` should always return {ok, Pid} or {error, Reason}, but
connecting to mqtt may throw out exceptions as it handles the
socket. But the caller couldn't have thought of the exception, he would
pattern match on the result of `emqx_client:start_link`, but it crashed!
- If the init work succeed but the connection failed, the caller couldn't
get a Pid from the return value, but indeed it was created inside the
emqx_client. This hides the fact that the Pid was created, and when the
Pid dies, the caller would receive an message from a Pid it doesn' know about.
This change divived these 2 work into 2 APIs:
- `start_link/1` is to build and verify the options, and returns {ok,Pid}
(on success) or {error, Reason} (on failure).
- `connect/1` is to send MQTT CONNECT, and returns {ok, MQTTResult::properties()} or
{error, MQTTReason}. MQTT reason codes will contains in the `MQTTReason`.
Add request & response support for CONNECT & CONNACK
Prior to this change, there is no validate and specified process for
Request-Response-Information and Response-Information
Also added basic Request/Response functionality to emqx_client implementation
Zaiming (Stone) Shi