Find a way to expose the flutter_tools daemon protocol to the devtools app

[jacob314]

This would enable supporting hot restart and hot reload robustly from the devtools app.

This feature request is similar in spirit to
#70

[jacob314]

One idea is to expose a way for VM Service clients to register their own service extensions.
These service extensions could be used to expose the flutter_tools daemon protocol, to expose IDE protocols like the analyzer protocol and methods to trigger navigation to specific source locations.

[devoncarew]

flutter_tools does expose hot reload to clients via service protocol 'services':

https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/vmservice.dart#L149

And the one for 'compileExpression': https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/vmservice.dart#L187

[jacob314]

Excellent! I didn't realize this existed.

[devoncarew]

It may or may not be quite all there for what we need, but we can flesh it out as necessary. I had wanted to add a simple pub-sub implementation to the vm service layer; this is close, and allows clients to communicate with each other.

[jacob314]

It appears it is close but not quite trivial to use. _registerService pretty much does the right thing but the registered service has a prefix indicating which client added it. openSourceLocation is the example closest to doing what we would want.

[jacob314]

https://github.com/jacob314/devtools/pull/new/support_services
Example steel thread adds support for services.

[kenzieschmoll]

Hot reload and hot restart are implemented. We listen for EventKind.kServiceRegistered events.
Closing this issue as obsolete.