How to use the auto function from async

async.auto is a method in the async library for JavaScript that automates the order of executing asynchronous functions based on their dependencies.

How does async.auto work?

async.auto is a method provided by the Async library for Node.js that allows you to define a set of dependent tasks with their requirements, then runs them in parallel or series and returns the result. It uses a dependency graph to determine the order in which the tasks should be executed based on their dependencies.

Ai Example

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const async = require("async");

const tasks = {
  task1: (callback) => {
    console.log("Task 1 started");
    setTimeout(() => {
      console.log("Task 1 done");
      callback(null, "Result 1");
    }, 2000);
  },
  task2: (callback) => {
    console.log("Task 2 started");
    setTimeout(() => {
      console.log("Task 2 done");
      callback(null, "Result 2");
    }, 1000);
  },
  task3: [
    "task1",
    "task2",
    (results, callback) => {
      console.log("Task 3 started");
      console.log("Task 1 results:", results.task1);
      console.log("Task 2 results:", results.task2);
      setTimeout(() => {
        console.log("Task 3 done");
        callback(null, "Result 3");
      }, 500);
    },
  ],
  task4: [
    "task3",
    (results, callback) => {
      console.log("Task 4 started");
      console.log("Task 3 results:", results.task3);
      setTimeout(() => {
        console.log("Task 4 done");
        callback(null, "Result 4");
      }, 250);
    },
  ],
};

async.auto(tasks, (err, results) => {
  if (err) {
    console.error("Error:", err);
  } else {
    console.log("All tasks done");
    console.log("Results:", results);
  }
});

In this example, async.auto is used to run a set of tasks in the correct order based on their dependencies. Each task is defined as a function, and the dependencies of each task are specified as an array of strings that match the keys of other tasks. When all the tasks are complete, the callback function is called with an object containing the results of each task.