Rename files inside zip archive in nodejs - node.js

Question

I am writing a nodejs script which should do the following:
Download a zip file
Remove the top level directory of the zip file (moving all files one folder up)
Upload the new zip file
Because the zip file is rather large, I would like to rename (or move) the files without unzipping and rezipping the file.
Is that possible?

Answer 1

Yes, it's possible
Using a library like adm-zip
var AdmZip = require('adm-zip');
//create a zip object to hold the new zip files
var newZip = new AdmZip();
// reading archives
var zip = new AdmZip('somePath/download.zip');
var zipEntries = zip.getEntries(); // an array of ZipEntry records
zipEntries.forEach(function(zipEntry) {
var fileName = zipEntry.entryName;
var fileContent = zip.readAsText(fileName)
//Here remove the top level directory
var newFileName = fileName.substring(fileName.indexOf("/") + 1);
newZip.addFile(newFileName, fileContent, '', 0644 << 16);
});
newZip.writeZip('somePath/upload.zip'); //write the new zip
Algorithm
Create a newZip object to temporarily hold files in memory
Read all entries in the downloaded zip. For each entry
Read the fileName. This includes the path
Read the file content using the fileName
Remove the top level directory name to get the newFileName
Add the fileContent in step 2 to the newZip giving it the newFileName from step 3
Finally, write out the newZip to disk giving it a new zipName
Hope that helps

Answer 2

You can use the great jszip library with async-promise style.
import jszip from 'jszip';
import fs from 'fs';
/**
* Move/rename entire directory tree within a zip.
* #param {*} zipFilePath The original zip file
* #param {*} modifiedZipFilePath The path where palace the modified zip
* #param {*} originalDir The original directory to change
* #param {*} destinationDir The new directory to move to.
*/
async function moveDirectory(zipFilePath, modifiedZipFilePath, originalDir, destinationDir) {
// Read zip file bits buffer
const zipFileBuffer = await fs.promises.readFile(zipFilePath);
// Load jszip instance
const zipFile = await jszip.loadAsync(zipFileBuffer);
// Get the original directory entry
const originalDirContent = zipFile.folder(originalDir);
// Walk on all directory tree
originalDirContent.forEach((path, entry) => {
// If it's a directory entry ignore it.
if (entry.dir) {
return;
}
// Extract the file path within the directory tree
const internalDir = path.split(originalDir)[0];
// Build the new file directory in the new tree
const newFileDir = `${destinationDir}/${internalDir}`;
// Put the file in the new tree, with the same properties
zipFile.file(newFileDir, entry.nodeStream(), {
createFolders: true,
unixPermissions: entry.unixPermissions,
comment: entry.comment,
date: entry.date,
});
});
// After all files copied to the new tree, remove the original directory tree.
zipFile.remove(originalDir);
// Generate the new zip buffer
const modifiedZipBuffer = await zipFile.generateAsync({ type: 'nodebuffer' });
// Save the buffer as a new zip file
await fs.promises.writeFile(modifiedZipFilePath, modifiedZipBuffer);
}
moveDirectory('archive.zip', 'modified.zip', 'some-dir/from-dir', 'some-other-dir/to-dir');
This is simply walking on all original directory tree entries and place them in the new directory tree.