JavaScript: Run a given array of promises in series

JavaScript fundamental (ES6 Syntax): Exercise-150 with Solution

Run Promises in Series

Write a JavaScript program to run a given array of promises in series.

• Use Array.prototype.reduce() to create a promise chain, where each promise returns the next promise when resolved.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2

// Define the runPromisesInSeries function
const runPromisesInSeries = ps => ps.reduce((p, next) => p.then(next), Promise.resolve());

// Define a delay function that returns a promise resolving after a specified time
const delay = d => new Promise(r => setTimeout(r, d));

// Executes each promise sequentially, taking a total of 3 seconds to complete
runPromisesInSeries([() => delay(1000), () => delay(2000)]);

Flowchart:

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