===== XMPP Chat =====

To support scalable text/audio/video chat through XMPP. Chat will be focused towards a taks(review or feedback).

===== Design =====

1. Each and every user is registered against an xmpp server when a user is created and his account does not exist already in the server.

2. Once a user opens a page he is connected to the xmpp server and the users with whom he can chat will have the chat related icons enabled. 

3. Chats are context specific.

=== Screen designs ===

1. Chat (on the same page)

Manager initiates: http://invis.io/VQ38BE8XU

Employee replies:http://invis.io/R338BFQ5V

2. Chat (on a different page)

Manager initiates: http://invis.io/DR38BGIUG

Employee replies: http://invis.io/Y238C6XWS

===== Implementation =====


Following are used for the implementation.

1. https://www.ejabberd.im/ - XMPP server with BOSH support

2. https://github.com/sstrigler/JSJaC/ - XMPP JS client.

3. https://xmpp4r.github.io/ - XMPP ruby client

4. https://github.com/valeriansaliou/giggle - XMPP jingle library which is used for audio/video chats.


=== Other libraries/alternatives explored ===

1. https://www.jsxc.org/

2. http://strophe.im/strophejs/

3. https://github.com/estos/strophe.jingle

=== To be done ===

1. Grouping chats by task and notifications.

2. Saving chat history.

===== Database Changes =====

**Table Name:** users (Following columns are added)

^Column Name  ^Type  ^Description  ^
|xmpp_login |String  |xmpp login  |
|encrypted_xmpp_password  |String | encrypted xmpp password  |


===== Setting up chat =====

=== Setup ejabberd ===

1. Download and install ejabberd (15.04 or above)
https://www.process-one.net/en/ejabberd/downloads

2. while setting up, please give  a hostname (ex - mylocal.com). This needs to be noted down.

3. Change the config settings. Config file can be found in your ejabberd directory under conf (ex - /opt/ejabberd-15.04/conf/ejabberd.yml)

Change "register:" (around line 481)
<code>
  register: 
    all: allow
    registration_timeout: infinity
</code>

Change "registration_timeout:" (around line 494)
<code>
registration_timeout: infinity //(yaml file level)
</code>


Enable "mod_ping"
<code>
mod_ping:
    send_pings: true
    ping_interval: 250
    timeout_action: none
</code>

3. Start/Restart ejabberd

4. Create a shared roster for every one. 

{{:shared_roster_all.png|Screenshot with information}}

5. Add a host entry for the IP pointing to the URL.

=== Configuring chat server ===

1. Configure the settings in config/chat.yml and enable chat. Sample settings for development environment look like below.
<code>
development:
  server: http://192.168.2.118:5280
  bosh: http://192.168.2.118:5280/http-bind
  websocket: ws://192.168.2.118:5280/websocket
  domain: mylocal.com 
  enabled: true
  create_xmpp_user: true
</code>

2. Create xmpp_login for existing users and populate thread id for older review assignments.

rake backfill:create_xmpp_account_for_users

rake backfill:populate_chat_thread_id_in_review_assignment