StairCase: Portable Flow-Control

Create portable & reusable sequences of functions.

Getting Started

1. Install staircase

   $ npm install staircase --save

2. Create a scheduler
3. Add steps to be called in series or parallel
4. Get the results

import Scheduler from "staircase";

const scheduler = new Scheduler("Hello", "World")

.series(
    // Synchronous
    (argumentOne, argumentTwo) => {
        return argumentOne;
    },
    // Asynchronous
    (argumentOne, argumentTwo, done) => {
        done(null, argumentTwo);
    }
)

.parallel(
    // Synchronous
    (argumentOne, argumentTwo) => {
        return argumentOne;
    },
    // Asynchronous
    (argumentOne, argumentTwo, done) => {
        done(null, argumentTwo);
    }
)

.results((error, data) => {
    if (error) { throw error; }
    data; // ["Hello", "World", "Hello", "World"];
});

Events

Set callback events to be called before and after each step.

scheduler

.on("step:before", step => {
	step.name; // name of the step about to be executed
	step.arguments; // arguments about to be sent to the step
})

.on("step:after", step => {
	step.name; // name of the step about to be executed
	step.arguments; // arguments about to be sent to the step
	step.error; // error returned by the step
	step.data; // data returned by the step
	step.duration; // duration of the step execution in ms
});

Apply Extra Arguments

It is possible to pass extra arguments to any step group by calling .apply() at the end of any .series, .parallel, or .step call.

import Scheduler from "staircase";

const scheduler = new Scheduler("Hello", "World")

.series(
    (appliedArgumentOne, appliedArgumentTwo, argumentOne, argumentTwo) => {
        return argumentOne + appliedArgumentOne;
    },
    (appliedArgumentOne, appliedArgumentTwo, argumentOne, argumentTwo, done) => {
        done(null, argumentTwo + appliedArgumentTwo);
    }
).apply(",", "!")

.series(
    (appliedArgumentOne, argumentOne, argumentTwo) => {
        return "How are";
    },
    (appliedArgumentOne, argumentOne, argumentTwo, done) => {
        done(null, appliedArgumentOne + "?");
    }
).apply("things")

.results((error, data) => {
    if (error) { throw error; }
    data.join(" "); // "Hello, World! How are things?"
});