added directory iterator

the above script iterates through all the directories recursively and list the files

Author: varun93

directory-iterator.js

@@ -0,0 +1,59 @@
+const fs = require("fs");
+
+const promisifyReaddir = path => {
+  return new Promise((resolve, reject) => {
+    fs.readdir(path, (error, data) => {
+      if (error) {
+        reject(error);
+      } else {
+        resolve(data);
+      }
+    });
+  });
+};
+
+const promisifyStat = path => {
+  return new Promise((resolve, reject) => {
+    fs.lstat(path, (error, data) => {
+      if (error) {
+        reject(error);
+      } else {
+        resolve(data);
+      }
+    });
+  });
+};
+
+const filterDirectories = async paths => {
+  const stats = await Promise.all(
+    paths.map(async path => {
+      const stat = await promisifyStat(path);
+      const isDirectory = stat.isDirectory();
+      return isDirectory ? path : undefined;
+    })
+  );
+  return stats.filter(path => path !== undefined);
+};
+
+const iterateDirectoryAsync = async directoryPath => {
+  let paths = await promisifyReaddir(directoryPath);
+
+  paths = paths.map(path => `${directoryPath}/${path}`);
+
+  const directories = await filterDirectories(paths);
+
+  const files = paths.filter(path => directories.indexOf(path) === -1);
+
+  storedFiles = storedFiles.concat(files);
+
+  await Promise.all(
+    directories.map(directory => iterateDirectoryAsync(directory))
+  );
+};
+
+const basePath = "DIRECTORY START PATH";
+let storedFiles = [];
+
+iterateDirectoryAsync(basePath).then(() => {
+  console.log(storedFiles);
+});