hatstall

Hatstall is the time it takes the Sorting Hat to consider into which house someone should be sorted.

hatstall plugs into sortinghat. It takes events and shovels them into function invocation requests for various backends. Comes with support for AWS Lambda and a pushing to a redis queue, which something like locavore can monitor.

Example

var invoker = hatstall('console');
var sortinghat = new SortingHat(new Firebase(...));

sortinghat.watch('/test/watch', invoker.run('test1'));

sortinghat.trigger('/test/trigger', invoker.trigger('test2'));

sortinghat.responder('/test/responder', invoker.responder('test3'));

API

hatstall(backend[, opts])

Creates a new invoker using the specified backend. opts are passed to the backend. Hatstall comes with:

• 'redis' - Puts invocation requests on a redis queue
• 'lambda' - Invokes functions in AWS Lambda
• 'internal' - Calls locavore directly. Pass in a Locavore instance.
• 'console' - Spits out the invocation requests on stdout. Useful for debugging.

You get an invoker instance back from hatstall(). It has:

invoke(fn, args[, cb])

Issues a function invocation request with the supplied args. If cb is specified, it will be called when the request is complete (not when the function is complete). If the request fails, the first argument will contain the err. (Your function may still fail to run or error. This callback only tells you that the request for invocation succeeded or failed.)

invoke also returns a promise for your convenience.

run(fn, deleteAfter)

Returns a function that when called will call invoke(fn, { path, key, data }). path, key, and data are populated from the Firebase Snapshot passed in.

If deleteAfter is true, the object will be deleted from Firebase upon a successful invocation request.

trigger(fn)

Calls run(fn, true).

responder(fn)

For use with responders.

job(fn[, args])

Returns a function that when called will call invoke(fn, args). Useful for invoking scheduled tasks that take the same arguments every time.