publishing v1 of action

node_modules/unzipper/lib/extract.js

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+module.exports = Extract;
+
+var Parse = require('./parse');
+var Writer = require('fstream').Writer;
+var path = require('path');
+var stream = require('stream');
+var duplexer2 = require('duplexer2');
+var Promise = require('bluebird');
+
+function Extract (opts) {
+  // make sure path is normalized before using it
+  opts.path = path.normalize(opts.path);
+
+  var parser = new Parse(opts);
+
+  var outStream = new stream.Writable({objectMode: true});
+  outStream._write = function(entry, encoding, cb) {
+
+    if (entry.type == 'Directory') return cb();
+
+    // to avoid zip slip (writing outside of the destination), we resolve
+    // the target path, and make sure it's nested in the intended
+    // destination, or not extract it otherwise.
+    var extractPath = path.join(opts.path, entry.path);
+    if (extractPath.indexOf(opts.path) != 0) {
+      return cb();
+    }
+
+    const writer = opts.getWriter ? opts.getWriter({path: extractPath}) :  Writer({ path: extractPath });
+
+    entry.pipe(writer)
+      .on('error', cb)
+      .on('close', cb);
+  };
+
+  var extract = duplexer2(parser,outStream);
+  parser.once('crx-header', function(crxHeader) {
+    extract.crxHeader = crxHeader;
+  });
+
+  parser
+    .pipe(outStream)
+    .on('finish',function() {
+      extract.emit('close');
+    });
+  
+  extract.promise = function() {
+    return new Promise(function(resolve, reject) {
+      extract.on('close', resolve);
+      extract.on('error',reject);
+    });
+  };
+
+  return extract;
+}