lib/zookeeper.js: add mkdirp

lib/zookeeper.js

@@ -1,6 +1,8 @@
 var EventEmitter = require('events').EventEmitter;
 var util = require('util');
 var _ = require('underscore');
+var path = require('path');
+var async = require('async');
 
 try {
   // as of node 0.6.x, node-waf seems to build to a different directory. grr.
@@ -281,3 +283,54 @@ ZooKeeper.prototype.a_delete_ = function a_delete_() {
   return this._native.a_delete_.apply(this._native, arguments);
 }
 
+ZooKeeper.prototype.mkdirp = function (p, cb) {
+  if(this.logger) this.logger("Calling mkdirp with " + util.inspect(arguments));
+  return mkdirp(this, p, cb);
+}
+
+//
+// ZK does not support ./file or /dir/../file
+// mkdirp(zookeeperConnection, '/a/deep/path/to/a/file', cb)
+//
+function mkdirp(con, p, callback) {
+  p = path.normalize(p);
+  var dirs = p.split('/').slice(1); // remove empty string at the start.
+
+  // console.log('dirs', dirs);
+
+  var tasks = [];
+  dirs.forEach(function(dir, i) {
+    var subpath = '/' + dirs.slice(0, i).join('/') + '/' + dir;
+    subpath = path.normalize(subpath); // remove extra `/` in first iteration
+    tasks.push(async.apply(create, con, subpath));
+  });
+  async.waterfall(tasks, function(err, results) {
+    if(err) return callback(err);
+    // succeeded!
+    return callback(null, true);
+  });
+}
+
+//
+// create(zookeeperConnection, '/some-path', cb)
+// if there is a problem:
+//    cb(error)
+// if the dir was created, or already exists:
+//    cb()
+//
+function create(con, p, cb) {
+  var data = 'created by zk-mkdir-p'; // just want a dir, so store something
+  var flags = 0; // none
+  con.a_create(p, data, flags, function(rc, error, zkPath) {
+    // already exists, cool.
+    // console.log('ZooKeeper.ZNODEEXISTS',ZooKeeper.ZNODEEXISTS);
+    if(rc == ZooKeeper.ZNODEEXISTS) {
+      return cb();
+    }
+    if(rc != 0) {
+      return cb(new Error('Zookeeper Error: code='+rc+'   '+error));
+    }
+    // sucessfully created!
+    return cb();
+  });
+}