I have a code that helps me rename multiple files with a data. In the data (rarityList) there is a name and a value for each file I have. For the sake of the post I just replaced the values with a dummy but you can imagine there is 500 of them.
It works and does the job but in a way that I did not intend. In the terminal it first prints 0(total) then copies all files and then renames it. But I was expecting to see something like Copying is done! and Renaming is done! and finally total number at the end of the terminal. Could you explain to me what I am missing here?
const fs = require("fs");
const path = "C:\\Users\\shepard\\Desktop\\Head";
const newPath = "C:\\Users\\shepard\\Desktop\\NewHead";
let files = fs.readdirSync(path);
const rarityList = [{name: "a", value: 3},{name: "b", value: 2}];
let total = 0;
const copy = async (_e) => {
fs.copyFile(path + "\\" + _e, newPath + "\\" + _e, err => {if (err) {console.log(err)}});
};
const rename = async (_e, _index) => {
let t = _e.replace(".png", "#" + rarityList[_index].value + ".png")
fs.rename(newPath + "\\" + _e, newPath + "\\" + t, err => {if (err) {console.log(err)}});
};
files.forEach(async (e) => {
await copy(e);
console.log("Copying is done!");
rarityList.forEach(async (element, index) => {
if (element.name == e.slice(0,-4)) {
await rename(e,index);
console.log("Renaming is done! for " + e + " with the rarity weight of " + rarityList[index].value);
total += rarityList[index].value;
};
});
});
console.log(total);Possibly not the best answer, but a solution:
const fs = require("fs");
const path = "C:\\Users\\shepard\\Desktop\\Head";
const newPath = "C:\\Users\\shepard\\Desktop\\NewHead";
let files = fs.readdirSync(path);
const rarityList = [
{ name: "a", value: 3 },
{ name: "b", value: 2 },
];
let total = 0;
const copy = async (_e) => {
fs.copyFile(path + "\\" + _e, newPath + "\\" + _e, (err) => {
if (err) {
console.log(err);
}
});
};
const rename = async (_e, _index) => {
let t = _e.replace(".png", "#" + rarityList[_index].value + ".png");
fs.rename(newPath + "\\" + _e, newPath + "\\" + t, (err) => {
if (err) {
console.log(err);
}
});
};
const renameFiles = async () => {
for (let e of files) {
await copy(e);
let index = 0;
for (let element of rarityList) {
if (element.name == e.slice(0, -4)) {
await rename(e, index);
console.log(
"Renaming is done! for " +
e +
" with the rarity weight of " +
rarityList[index].value
);
total += rarityList[index].value;
}
index += 1;
}
}
console.log('in async func', total);
};
renameFiles();
console.log('out of async function', total);
The trick is that the async function is not waited for, so total isn't updated at the "top level". You can do a "top level" await like this:
const fs = require("fs");
const path = "C:\\Users\\shepard\\Desktop\\Head";
const newPath = "C:\\Users\\shepard\\Desktop\\NewHead";
let files = fs.readdirSync(path);
const rarityList = [
{ name: "a", value: 3 },
{ name: "b", value: 2 },
];
let total = 0;
const copy = async (_e) => {
fs.copyFile(path + "\\" + _e, newPath + "\\" + _e, (err) => {
if (err) {
console.log(err);
}
});
};
const rename = async (_e, _index) => {
let t = _e.replace(".png", "#" + rarityList[_index].value + ".png");
fs.rename(newPath + "\\" + _e, newPath + "\\" + t, (err) => {
if (err) {
console.log(err);
}
});
};
const renameFiles = async () => {
for (let e of files) {
await copy(e);
let index = 0;
for (let element of rarityList) {
if (element.name == e.slice(0, -4)) {
await rename(e, index);
console.log(
"Renaming is done! for " +
e +
" with the rarity weight of " +
rarityList[index].value
);
total += rarityList[index].value;
}
index += 1;
}
}
console.log("in function", total);
};
(async function() {
await renameFiles()
console.log(total)
}());