Promisified version of yauzl for unzipping ZIP files.

npm install yauzl-promise

const {pipeline} = require('stream/promises');
const zipFile = await yauzl.open('/path/to/file.zip');
try {
  for await (const entry of zipFile) {
    if (entry.fileName.endsWith('/')) continue;
    const readStream = await entry.openReadStream();
    await pipeline(readStream, writeStream);
  }
} finally {
  await zipfile.close();
}

These methods all work as before, but return a Promise rather than taking a callback.

const yauzl = require('yauzl-promise');
const zipFile = await yauzl.open('/path/to/file.zip');

lazyEntries option is automatically enabled. Get file entries using methods listed below.

autoClose option is automatically disabled. ZipFiles must be closed manually with .close().

Closes file and returns Promise which resolves when all streams are closed.

Files must be closed when finished with to avoid resource leakages.

const zipFile = await yauzl.open('/path/to/file.zip');
await zipFile.close();

Same as original yauzl method, but returning a promise. Promise resolves to an instance of yauzl.Entry, or rejects if there is an error.

const entry = await zipFile.readEntry();
console.log(entry);

Calling .readEntry() again returns the next entry. When there are no entries left, it returns null.

Read several entries and return as an array.

const entries = await zipFile.readEntries(3);
entries.forEach(console.log);

If numEntries is 0, null or undefined, reading will continue until all entries are read.

WARNING: This is dangerous. If ZIP contains a large number of files, could lead to crash due to out of memory. Use .walkEntries() or async iteration instead.

Read several entries and call callback for each.

If callback returns a promise, the promise is awaited before reading the next entry. If callback throws an error or returns a rejected promise, walking stops and the promise returned by .walkEntries() is rejected.

Returns a promise which resolves when all have been read.

await zipFile.walkEntries(entry => {
  console.log(entry);
});
console.log('Done');

If numEntries is 0, null or undefined, reading will continue until all entries are read.

ZipFiles can be used as async iterators, iterating over entries.

const zipFile = await yauzl.open('/path/to/file.zip');

const entries = [];
for await (const entry of zipFile) {
  entries.push(entry);
}

Same as original method but returns promise of a stream.

const readStream = await zipFile.openReadStream(entry);
readStream.pipe(writeStream);

As above, but called on an Entry object.

const entry = await zipFile.readEntry();
const readStream = await entry.openReadStream();
readStream.pipe(writeStream);

ZipFile objects are from a subclass of yauzl's original ZipFile class. They are event emitters but do not emit any of the events original yauzl module emits (entry, end, close or error).

These events are replaced by the resolution/rejection of promises returned by the methods listed above.

If an error event is emitted unexpectedly within yauzl at a time when no operation (readEntry() etc) is in progress, that event is consumed to prevent the process from crashing. The next time readEntry(), close() or openReadStream() is called, the promise returned from that method will reject with the previously emitted error.

Promises returned by default are native JS Promises.

.usePromise() returns a new yauzl object where the methods return promises from the specified Promise constructor.

const Bluebird = require('bluebird');
const yauzl = require('yauzl-promise').usePromise(Bluebird);

const p = yauzl.open('/path/to/file.zip');
assert(p instanceof Bluebird);

NB This does not alter the original yauzl object, only the one returned from .usePromise().

const Bluebird = require('bluebird');
const yauzl = require('yauzl-promise');
const yauzlBluebird = yauzl.usePromise(Bluebird);

const p = yauzl.open('/path/to/file.zip');
assert(p instanceof Promise);
assert(!(p instanceof Bluebird));

const p = yauzlBluebird.open('/path/to/file.zip');
assert(p instanceof Bluebird);
assert(!(p instanceof Promise));

.useYauzl() method promisifies a specific yauzl object.

Only useful if you have a modified version of yauzl which you want to promisify.

const yauzlCrc = require('yauzl-crc');
const yauzl = require('yauzl-promise').useYauzl(yauzlCrc);

The yauzl object passed is cloned before it is modified, unless you set clone option to false:

const yauzlFork = require('my-yauzl-fork');
const yauzl = require('yauzl-promise').useYauzl(yauzlFork, { clone: false });
assert(yauzl === yauzlFork);

.use() method does both of the above.

const yauzlCrc = require('yauzl-crc');
const Bluebird = require('bluebird');
const yauzl = require('yauzl-promise').use(Bluebird, yauzlCrc);

The yauzl object passed is cloned before it is modified, unless you set clone option to false:

const yauzlFork = require('my-yauzl-fork');
const yauzl = require('yauzl-promise').use(Bluebird, yauzlFork, { clone: false });
assert(yauzl === yauzlFork);

This module follows semver. Breaking changes will only be made in major version updates.

All active NodeJS release lines are supported (v16+ at time of writing). After a release line of NodeJS reaches end of life according to Node's LTS schedule, support for that version of Node may be dropped at any time, and this will not be considered a breaking change. Dropping support for a Node version will be made in a minor version update (e.g. 1.2.0 to 1.3.0). If you are using a Node version which is approaching end of life, pin your dependency of this module to patch updates only using tilde (~) e.g. ~1.2.3 to avoid breakages.

Use npm test to run the tests. Use npm run cover to check coverage.

See changelog.md

If you discover a bug, please raise an issue on Github. https://github.com/overlookmotel/yauzl-promise/issues

Pull requests are very welcome. Please:

• ensure all tests pass before submitting PR
• add tests for new features
• document new functionality/API additions in README
• do not add an entry to Changelog (Changelog is created when cutting releases)