在Node.js异步管道中调用正确的对象方法

Question

I want to use some Node.js async pipeline operations (such as parallel and waterfall ) to call instance methods inside an object.

I am using the following format to preserve the correct this reference inside the pipeline functions, since, normally, inside pipeline functions this references the pipeline object itself.

var jobThis = this;
async.waterfall(
    [
        function(cb) { jobThis.getParseInstalls(cb); },
        function(prev, cb) { jobThis.getParseIAPs(prev, cb); },
    ],
    callback
);

I want the stages of the pipeline to be able to access (but not modify) a settings object belonging to the wrapping object.

I feel like this constitutes bad style. Is there a cleaner way to achieve this goal? Am I simply not supposed to use methods and async ?

Answer 1

In the end, I realized that simply using function.bind was the cleanest way to do this (and also, self is a bit clearer than anything else):

var self = this;
async.waterfall([
     self.getParseInstalls.bind(self),
     self.doSomethingElse.bind(self),
 ],
 callback
);