javascript - Node.js wait for all files read in the loop

I am new to the javascript/node.js event driven paradigm.

I need to stop the for after forEach to make sure all files have been read and then I continue. How should I implement wait_for_all_files_read() in this context?

my_list.forEach(function(element) {
  fs.readFile(element.file_path, function(err, data)  {
    if(err) throw err;
    element.obj=JSON.parse(data);
  });
});
wait_for_all_files_read(); <-----------
analyze(my_list)

Neither solution [1] or [2] work for me.

Answer

How I would do that:

1. Promisify fs.readFile (by using, for example Bluebird)


2. Mark the function as async


3. Make a list of callbacks (my_list.map instead of forEach)



4. "await Promise.all(myListOfCallbacks)"


5. Next line after await will be executed after all the operations been finished

Something like that:

const {promisisfy} = require('util')
const fs = require('fs')

const readFile = promisify(fs.readFile)

const fileNames = getFilenamesArray();

async function executeMe() {
  try {
    const arrayWithFilesContent = await Promise.all(
      fileNames.map(name => readFile(name))
    );
    return analyze(arrayWithFilesContent);

  }
  catch (err) {
    handleError(err)
  }
}

executeMe();