anantn’s gists

anantn / firebase_workers.js

Created December 27, 2012 22:11

Firebase: Implementing a worker queue pattern using firebase_queue_pop.js

	var Firebase = require("./firebase-node.js");

	function Queue(ref) {
	this._ref = ref;
	}

	Queue.prototype.pop = function(cb) {
	this._ref.startAt().limit(1).once("child_added", this._pop.bind(this, cb));
	}

anantn / firebase_queue_pop.js

Last active December 10, 2015 01:19

Firebase: Using .push() to maintain a queue and ensuring only one client is able to obtain the head of the queue at a time.

	var Firebase = require("./firebase-node.js");

	function Queue(ref) {
	this._ref = ref;
	}

	Queue.prototype.pop = function(cb) {
	this._ref.startAt().limit(1).once("child_added", this._pop.bind(this, cb));
	}

anantn / firebase_remove_pushed.js

Last active February 19, 2019 23:45

Firebase: Removing an item you've pushed. This snippet shows how to remove an object that you just added using push().

	function pushSomething(ref) {
	// Let's push something. push() returns a reference that you can hold onto!
	var justPushed = ref.push({test: "push"});
	// We return a reference, but you can also return the name of the newly
	// created object with .name().
	return justPushed;
	}

	function removeItem(ref) {
	// Now we can get back to that item we just pushed via .child().

anantn / firebase_first_item.js

Last active March 4, 2016 00:04

Firebase: Get the first item in a list. This snippet retrieves only the first item in a list.

	function makeList(ref) {
	var fruits = ["banana", "apple", "grape", "orange"];
	for (var i = 0; i < fruits.length; i++) {
	ref.push(fruits[i]);
	}
	}

	function getFirstFromList(ref, cb) {
	ref.startAt().limit(1).once("child_added", function(snapshot) {
	cb(snapshot.val());

anantn / firebase_player_assignment.js

Last active January 14, 2023 01:51

Firebase: Assigning players in a multiplayer game. This snippet assigns you a spot in a game if the game isn't full yet.

	function go() {
	var userId = prompt('Username?', 'Guest');
	// Consider adding '/<unique id>' if you have multiple games.
	var gameRef = new Firebase(GAME_LOCATION);
	assignPlayerNumberAndPlayGame(userId, gameRef);
	};

	// The maximum number of players. If there are already
	// NUM_PLAYERS assigned, users won't be able to join the game.
	var NUM_PLAYERS = 4;

anantn / firebase_create.js

Last active November 20, 2023 23:17

Firebase: Creating data if it doesn't exist. This snippet creates a user only if it doesn't already exist.

	function go() {
	var userId = prompt('Username?', 'Guest');
	var userData = { name: userId };
	tryCreateUser(userId, userData);
	}

	var USERS_LOCATION = 'https://SampleChat.firebaseIO-demo.com/users';

	function userCreated(userId, success) {
	if (!success) {

anantn / firebase_detect_data.js

Created December 18, 2012 00:54

Firebase: Detecting if data exists. This snippet detects if a user ID is already taken

	function go() {
	var userId = prompt('Username?', 'Guest');
	checkIfUserExists(userId);
	}

	var USERS_LOCATION = 'https://SampleChat.firebaseIO-demo.com/users';

	function userExistsCallback(userId, exists) {
	if (exists) {
	alert('user ' + userId + ' exists!');

anantn / datachannels.js

Created October 31, 2012 22:48

Data Channel Example

	/**
	* Assume we've connected a PeerConnection with a friend - usually with audio
	* and/or video. For the time being, always at least include a 'fake' audio
	* stream - this will be fixed soon.
	*
	* connectDataConnection is a temporary function that will soon disappear.
	* The two sides need to use inverted copies of the two numbers (eg. 5000, 5001
	* on one side, 5001, 5000 on the other)
	*/
	pc.connectDataConnection(5001, 5000);

anantn / tamejs_gum.js

Created October 18, 2012 01:14

TameJS wrapper for getUserMedia


	function myGetUserMedia(constraints, cb)
	{
	function errCb(code)
	{
	cb(code, null);
	}

	function successCb(stream)
	{

anantn / getUserMediaDevices.html

Created September 18, 2012 17:41

navigator.mozGetUserMediaDevices Example

	<html>
	<body>
	<h1>Device Test</h1>
	<ul id="contents">
	</ul>
	<video id="tehvideo"/>
	<audio id="tehaudio"/>
	<script>
	var devices;
	var nav = navigator.QueryInterface(Components.interfaces.nsINavigatorUserMedia);

Anant Narayanan anantn