Use Ned robot's TCP server
##########################

Ned is permanently running a TCP Server which can interpret several requests.
This server is built on top of the :doc:`Python ROS Wrapper <../packages/ros_wrapper>`.

It offers a simple way for developers to create programs for robot and
to control them via remote communication on a computer, on a mobile
or any device with network facilities.

Programs can communicate through network TCP with the robots
in any language available.

Connection
----------
To access the server, you will have to use to robot's IP adress and communicate 
via the **port 40001**.

Communication
-------------
Only one client can communicate with the server (reconnection effective but no multi-clients).

The server answers only after the command is done, so it can't deal with multiple commands at the same time.

Packet convention
-----------------

General format
^^^^^^^^^^^^^^

For easier usage and debugging, the communication is based on JSON format.

Every package have this following shape: ``<json_packet_size>{<json_content>}<payload>``.

The JSON packet size is an unsigned short coded on 2 bytes.

The JSON contains command's name & params.

Payload contains *heavy* data like an image.

Request
^^^^^^^

Format - Request
""""""""""""""""

As no function requests a payload in input, requests have the following.

Format: ``<json_packet_size>{'param_list': [<param_1>, <param_2>, ....], 'command': <command_str>}``

Examples - Request
""""""""""""""""""""""""""""

Calibrate auto: ``{'param_list': ['AUTO'], 'command': 'CALIBRATE'}``

Move joints: ``{'param_list': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0], 'command': 'MOVE_JOINTS'}``

Answer
^^^^^^

Format - Answer
"""""""""""""""

Firstly, answers indicate to the user if its command has been well executed.
This is indicated in the JSON by the parameter "status".

A successful answer will have the format:

``{'status': 'OK', 'list_ret_param': [<param_1>, <param_2>, ....], 'payload_size': <payload_size_int>, 'command': <command_str>}<payload_str>``

An unsuccessful answer will have the format:
``{'status': 'KO', 'message': <message_str>}``

Examples - Answer
"""""""""""""""""
Calibrate Auto:
``{'status': 'OK', 'list_ret_param': [], 'payload_size': 0, 'command': 'CALIBRATE'}``

Get Pose:
``{'status': 'OK', 'list_ret_param': [0.2, 0.15, 0.35, 0.5, -0.6, 0.1], 'payload_size': 0, 'command': 'GET_POSE'}``



Commands enum for TCP server
----------------------------
.. automodule:: niryo_robot_python_ros_wrapper.ros_wrapper_enums
    :members: CommandEnum
    :undoc-members:
    :exclude-members:
    :member-order: bysource
    :noindex: