Devtools plans

Design

Devtools task:

• loops accepting connections, spawns a new task for each client
• home of actor registry - hashmap of actor IDs (strings like "tab1") to boxed Actor traits that can be cast to concrete actor types encapsulating immutable state

Devtools client task:

• loops reading the socket stream
• accepts and produces JSON wire protocol: https://wiki.mozilla.org/Remote_Debugging_Protocol_Stream_Transport
• sends synchronous messages to script task to perform operations such as:
• evaluating JS in the current global, return result
• enumerating the properties on a JS object

Script task:

• polls devtools port for pending requests
• pins/unpins arbitrary JS values (including DOM object reflectors) as required (https://wiki.mozilla.org/Remote_Debugging_Protocol#Grips)

Architecture

• Devtools->Script messages defined in a new devtools_traits crate that script/devtools depend upon
• Constellation provides optional devtools receiver to each new script task
• Script task notifies devtools task of each new global created (need bidirectional communication)
• Constellation creates new actor for each global, removes actor when global disappears

Miscellaneous, useful projects

• Report live CSS errors to remote console
• Report cached CSS errors to remote console
• Create new, exciting tools outside of the standard set - simple power monitor example

Useful links

https://developer.mozilla.org/en-US/docs/Tools/Web_Console/remoting https://wiki.mozilla.org/Remote_Debugging_Protocol_Stream_Transport https://wiki.mozilla.org/Remote_Debugging_Protocol

• http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/main.js?force=1 (base server stuff)
• http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/ (home of all actor implementations for server side)
• http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/webconsole.js?force=1 (the webconsole server actor implementation)
• http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/webconsole/client.js?force=1 (the webconsole client actor implementation)
• http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/script.js#1956 (grip creation)