CloudServices/FirefoxMobileServices/ChannelService

Last updated: 2014/03/12

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Overview

Channel Service is a service for Mozilla Cloud Services that need to communicate with a Firefox OS client-side component.

Project Contacts

Principal Point of Contact (US) - Ben Bangert bbangert@mozilla.com

Principal Point of Contact (EU) - Tarek Ziade tziade@mozilla.com

Goals

To develop a single multiplexed communication channel between FxOS devices and Mozilla Cloud Services.

This should result in:

• Cleaner client-side services code in the FxOS parent process
• Clean separation between the code handling the persistent connection between the device and Cloud Services
• Ability to easily update client-side service code without affecting complex channel code
• Ability to easily update the server-side code for higher client handling efficiency without changing Cloud Services code

Use Cases

Push

The first candidate for using the ChannelService is Push, which is already on FxOS. At the moment the code handling the socket connection is mixed in with the code handling the DOM API's for Push. By splitting the channel out, future Push updates could be easier to land in the client.

Presence

The Presence project would benefit from having an easier client-side API to use for talking over a single shared channel.

Requirements

• Client-side JSM developer familiar with Push's implementation that can split out the socket handling portion
• Client-side Push JSM developer to refactor the client-side portion to use the new FxOS Channel Service
• Server-side dev's to implement the new Mozilla server-side portion
• Server-side Push dev's to restructure Push to utilize the Mozilla Cloud Channel Service

Design

Platform Requirements

Firefox OS Modifications

Currently there's a PushService in the parent process. This proposal changes the structure.

• A thread will be launched from the parent process (referred to as the 'Services' Thread)
• The Services thread will have two portions running in it to begin with
  • channel.jsm - Channel handling code, split out from the current PushService.jsm, that handles the connection and implements a basic API for other code that is in the Services Thread
  • push.jsm - Push daemon refactored to utilize the Channel API. PBackground will likely need to be used to have the DOM API call into this thread hanging off the main thread

The Channel API will allow other code running in the Services Thread to hook in via Events and direct Calls:

Events (to register for):

• OnConnect (called anytime the connection is established)
• OnDisconnect (called if the connection is interrupted)
• OnMessage (called when a message is received over the channel for this service)

API Calls:

• Send(payload, service) - Send the payload over the channel. It will end up in the server-side service handling it. (ie. if push.jsm wanted to send a call to the Push service, it would call Send('whatever', 'push') )

Cloud Services Channel Service

The Cloud Services Channel Service (fondly pronounced koos-koos) handles the server-side termination of the channel from each device.

Push Server Modifications

The Push server service will need to be modified to work with the Cloud Services Channel Service.

Code Repository

Links to the published code bases

Release Schedule

Predicted code delivery dates

QA

Points of Contact

Engineer - Name contact@info

Security and Privacy

Fill out the security & privacy bug template: https://bugzilla.mozilla.org/form.moz-project-review (https://wiki.mozilla.org/Websites/Kick-Off_Form)

For security reviews, there's: https://wiki.mozilla.org/Security/ReviewProcess

Review Status

Bugzilla Tracking # - see https://wiki.mozilla.org/Security/Reviews

Operations

Deployment Architecture

Bugzilla Tracking # -