Add a context to cmds.Request

[whyrusleeping]

Currently (unless I'm missing something) we have no way of allowing the user to cancel a command. If we add in a context to the request handler it will allow us to have a mechanism to cancel commands with.

[jbenet]

@whyrusleeping yep, the context should be cancelled if/when the request's connection terminates.

[jbenet]

it's gonna get confusing cause the request already has a context (it's something else atm).

[jbenet]

related: #242

[jbenet]

this is done. just needs to be wired to more commands (ipfs refs does it, albeit in avery ugly way (see that writer trick)

[rht]

(ipfs refs does it, albeit in avery ugly way (see that writer trick)

Does this refer to https://github.com/ipfs/go-ipfs/blob/master/core/commands/refs.go#L105?
Which commands don't have request context?

[jbenet]

@rht not sure, we should go through all of them and make sure all the ctx related thing derive from req.Context()

[whyrusleeping]

yeah, i recently refactored and made the req.Context() more reliable, and also made it respect the global timeout flag. We should go through and make sure that it is used correctly all over the codebase.