Making Some Promises (in Parse, but also relevant to jQuery and Backbone)

What a confusing topic. Unfortunately, if you start wanting to add "library" features to your code, like I did, you have to study Promises.

These are notes about Parse.Promises, and the end product is a small object that caches models.

Please Excuse the Blandeness

Ever have one of those days when the layout looked great in the HTML mock-up, but when it was copied into the theme, it just wasn't right?

That's why I'm using Garland again.

Some Parse.com Cloud Code Gotchas

Getting back into CC has been full of annoying gotchas.

console.log() prints incorrectly

It stringifies the objects instead of using the formats favored by FireBug and Chrome's dev tools. So you will see things like {"foo":1} which aren't plain JS objects, but are really Parse Objects. Parse Object properties are accessed via get() and set().

Assume printed objects are really Parse Objects, which are like Backbone objects, and have a get() and set() method.

How do you get to the object that was saved?

request.object

Translating Angular Events into D3 Events

Converting or translating Angular events into d3 events was a lot easier than I thought it would be. Here's the code:

disp = d3.dispatch('resize');
angular.element(window).bind('resize', function() {
    disp.resize('foobar');
});

disp.on('resize', function(arg) {
    console.log(arg);
    // resize code is here
});

DOM tests in Jasmine

This continues some notes about working on sf-active-js, moving it to a contemporary Javascript development environment.

Here's a Jasmine spec to instantiate an HTML5 widget and test a few of the method calls. These method calls cause changes in the DOM, and these tests verify that the changes happened.

describe("comment", function() {
    var comment;
    beforeEach(function() {
        var elements = $('<div id="disclose"></div><div id="edit"></div>');
        $('body').append(elements);
        comment = Comment('#edit', '#disclose');
    });

Browserify libraries that can be tested with Jasmine... before they are rolled up by Browserify

This is part of a series of notes about bringing a JS project, sf-active-js, over to a contemporary Javascript development environment.

This is a trick to write modules that are testable in a browser, without subjecting the test to Browserify. Why?

I want to develop without the compilation step. It's easier and faster to work in the browser. (This particular app is mostly DOM manipulation, so headless isn't important.) Once the module has settled down, it can be added to the library.

The rest of this note assumes you know the Jasmine sample test runner included with the distro.

Notes on migrating to a contemporary javascript development environment

I'm writing this after writing the first two notes in this series about migrating sf-active-js to a contemporary Javascript development environment.

I wrote the original experiment a couple years ago. It's a JS client that retrieves some json data from the la.indymedia.org server, and displays it. I ran out of time, and didn't finish it then.

Upon revisiting the code, I found it a little confusing. It was around 800 lines of jQuery-style JS.

d3 dispatch (the d3 event system) notes

Learning d3 events this afternoon. These are the notes I'm taking while I'm learning it. I hope it helps.

It's called d3.dispatch. d3.dispatch('eventname1','eventname2') returns an object that manages setting event handlers, and dispatching events. The event system isn't global (unlike in most frameworks, where the event system appears to be globally available)- it's contained entirely within the object.

var dispatch = d3.dispatch('say');

That created an object that has a method dispatch.say() that dispatches/rasies/throws/broadcasts the "say" event to the listeners.

How many steps are there in a simple user registration and login?

We all take it for granted that most sites will have a user registration system, and way to log in. We're used to it, and most people are unaware of how complex it is.

So, how complex is it?

It's around 15 different steps or screens.

Fifteen.

I've done it a dozen times, and I think that's about right.

Bitten by the "this" scope issue in JavaScript callbacks

I took a step away from Angular and jQuery style coding conventions and dropped back to the traditional JS-style OOP, mainly because I wanted to get familiar with regular JS programming using the MDN docs, and learn the new HTML5 calls (which aren't new anymore).

I ended up coding using an MVC style, and consequently, added an event handling system. It was easy-but-cheesy so I eneded up using Backbone's event system. (It makes me look more hip.)

BTW, here's one way to use Backbone events within traditional JS code:

FooController = function() {
  var obj;

Parallax Effect

This is a short snippet of code to do the popular "parallax" effect for headings. This code has two boxes. The second box helps you see how to deal with a box that's not at the top of the page.

There's not much to it. You make some boxes and set the background-position based on the window.scrollY value.


<html>
    <head>
        <style type="text/css">
            #box1 {
                height: 350px;
                background-image: url(trafficjam.jpg);
            }
            #box2 {
                height: 350px;

Shorter code with functional-style programming in PHP.

So, I'm doing wordpress programming, and one of the headaches is that they store serialized objects in the database with the update_option() and related functions.

This makes querying some data difficult. Here's an example of the data structure I was dealing with (it stores sidebar settings).

Array
(
    [wp_inactive_widgets] => Array
        (
        )

    [sidebar-1] => Array
        (
            [0] => search-2
            [1] => recent-posts-2
            [2] => recent-comments-2

PulseAudio Microphone Not Working in Skype or Gnome PulseAudio

This took forever to fix. I upgraded the computer two versions of Ubuntu ago, and ever since then, the front mic stopped working.

It could be the mic's wire or the mic, but even a standalone mic wasn't working. It worked OK with Audacity, which uses Alsa.

It turned out the problem was that the Sound control panel in Gnome didn't work. Somehow, the system decided to change the input from Analog to Digital SPDIF. I don't use SPDIF.

WordPress Unit Tests in the Main Directory

I'm hacking some of the original WP files. Not the smartest thing to do, but the options are to replace the functions, or alter them, because a plugin isn't going to work.

So, I needed to run tests in the main program. Here's the quck howto.

Install wp-cli and get it working.

Then, go into your wp root and type:

wp scaffold plugin-tests --dir=.

Then run the installer script:

bin/install-wp-tests.sh wordpress_test root '--password--'

WordPress wp-signup headaches, and refactoring.

I've been modifying the wp-signup script a lot, and figured out a better pattern for doing these screens. This technique works more like "views and controllers", so it's one step closer to MVC.

WP doesn't have routes, but the wp-signup script has a paramter named "stage" that specifies the next state. It's effectively a route.

There are two types of stages: showing a form, or validating a form.

When you validate a form, you see if there are errors. If there are, you show the form, with error messages. If there are no errors, you commit the changes, and then show the next form.

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