no more four-eighty-six » open source

finishing up the StatusNet plugin for popcorn-js

stan — Thu, 15 Dec 2011 01:57:20 +0000

Well, it’s been an interesting journey trying to finish the status.net plugin for popcorn-js. The past weekend I’ve been busy getting it finished in between studying for exams. I had finished writing the plugin and a demo page for it, but I needed to write unit tests for it using the qunit framework. I had some troubles getting the test to work properly, but I hopped onto the #popcorn channel on IRC and dseif was very helpful and supportive in looking over my code and my unit test – a pre-unit review review, so to speak. He helped me figure out writing tests, and also pointed out an initial flaw in my plugin – that if you rewind or restart the popcorn video, the events would not reappear (commit f7 on the statusnet branch.) He gave some pointers on how to go about fixing that issue, and I ended up rewriting a lot of my plugin code. I had a lot of code in a separate function that could have been moved into the setup function of the plugin; additionally I altered the functionality of my plugin to do css display changing on the start and end function so that the statusnet events would be able to appear and reappear even after replaying the video.

Unfortunately, due to the limitations of the status.net javascript API, the plugin will only work when run against your own instance of StatusNet. As quoted directly from the statusnet api wiki:

Let’s make the Connection First

First you need to acquire a Consumer Key and a Secret for your callback url (which is your webpage)
you can get them from here – http://mystatus.net/settings/oauthapps (http://mystatus.net – change this with your StatusNet URL)
Then paste following code in the head section of your web page of blog

The api requires a unique customer key and secret to work. So as far as I understand, unless someone else gave your their own consumer key and secret (who would do that?), you would not be able to create widgets for them.

In any case, I had finally finished the plugin, the demo, and the unit tests. So on Sunday I put it up for review. cadecairos reviewed it on Monday, and after seeing that the plugin required an instance of StatusNet to run properly, said that while the plugin was interesting, he was unable to include it in the official repo until the structure of the plugin community was finalized. But who knows. Maybe one day the StatusNet api will become more flexible and thus allow the statusnet plugin to really come alive.

As always, the plugin is available at https://github.com/nm486/popcorn-js/tree/statusnet under the plugin/statusnet folder, latest commit. Thanks to everyone involved in helping make this an interesting learning experience for me into the world of open source. I wish it worked out better in the end.

writing a mouselocklost event mochitest

stan — Fri, 02 Dec 2011 07:02:44 +0000

So on Tuesday I “volunteered” to write a Mochitest for Test #23 (scroll down to tests, then find 23), which was to test the following requirement for our implementation of MouseLock in Firefox:

When mouse lock is lost or disabled for any reason user agents must fire an event named mouselocklost with its bubble attribute set to true to the mouse lock target element

Anyway while writing my Mochitest, I discovered there was a slight typo in the spec: a DOM event does not contain an attribute called “bubble” – its actually “bubbles”. (emphasis on the “s” at the end). This threw me off for the longest time when running my test, as my test kept failing when testing to see if event.bubble === true !

Aside from that, however, it was mostly alright. I used the Mochitest template provided by Raymond Hung and used Diogo Monteiro’s fullscreen Mochitest as a springboard for writing my own test. There was some trial and error in getting my test to run properly but I got it to behave the way I wanted it to in the end.

back in business: altering mouse x,y coordinates in FF

stan — Thu, 17 Nov 2011 00:21:24 +0000

After trying last night in vain trying to get the MSVCR100d.dll issue fixed on my desktop, I’ve migrated over to my laptop. It’s not the beast that my desktop is, but is quite modern with a quad core CPU, bundles of RAM, and a SSD for speedy I/O operations. Anyway, after getting everything set up, I tried building a debug build of firefox…and it worked! Let’s hope it stays that way. Anyway, my first goal was to get up to speed and get Firefox to report incorrect screen position values. Following the discussion we had in class, I found nsDOMMouseEvent.cpp, and after inspecting the relevant source code, decided to go one level deeper, and modified the return value of the GetScreenPoint function:

return nsIntPoint(nsPresContext::AppUnitsToIntCSSPixels(offset.x * factor * 9999),
nsPresContext::AppUnitsToIntCSSPixels(offset.y * factor));

And lo and behold:

Okay, now let’s get cracking on adding the two new attributes to the MouseEvent class. Stay tuned.

unexpected firefox build problem

stan — Tue, 15 Nov 2011 06:57:04 +0000

So here I was, hacking away at Firefox trying to alter mouse co-ordinate code. I probably did at least five top-level builds prior trying to get a feel of where the relevant source code was. Then, after my latest change, I try to build again, and this s*** happens:

Why did this happen, after a whole bunch of previously successful builds? What happened to my computer in the 10 minutes between my last successful build and this error? I don’t know. For sure I had everything required to build Firefox before. Tried googling, found a whole bunch of results, including something here on the mozillaZine forums: http://forums.mozillazine.org/viewtopic.php?f=23&t=1913225. So I tried redownloading and repairing my VC++2010 redist. No luck. Tried redownloading the whole mozilla-central branch again from github, no dice. I’ll try to manually redownload this missing .dll file and see if i can put in the right spot somewhere. According to the forum this problem was supposed to have been fixed with more recent builds? maybe not. Looks like I’ll have to ask for help.

firefox built in windows success

stan — Thu, 10 Nov 2011 00:04:31 +0000

ran into two errors trying to build firefox but i managed to overcome them both: first error was the windows line ending error. solution 3 at the wiki here works quite nicely for a quick fix.

the second error was trying to install the June 2010 DirectX SDK. I got an error at the end of installation S1023 – that was because I had a version of Microsoft Visual C++ 2010 that was too recent (more recent than the DirectX SDK) – the installer was getting hung up on that. The fix was the uninstall the Redist of C++ 2010 that has a version number greater than 10.0.30319 (mine was like 4xxxx). Install proceeded like a charm.

anyway, mission success! let the printf hacking commence.

milestone 0.2 going to be late

stan — Fri, 28 Oct 2011 04:07:12 +0000

On the good side of things I managed to get in touch with JSilver999 to talk about GameSaver. Apparently he’s done a lot of work recently and has resolved most if not all of the outstanding stories on Pivotal. There’s still plenty of work to be done, and he helped me out getting the node.js server up (turns out i’m going to have to run *nix on a VM to get this server going). Anyway, all of these unforeseen delays mean I’ll have to postpone my 0.2 for a little bit longer – and yes, I know that includes my popcorn.js plugin (it’s almost done! got an instance of status.net running on my own server now, just need to run my plugin against the status.net instance to see if the widgets come up). Hopefully I’ll get the plugin out by tomorrow or the weekend at the latest.

Working on GameSaver, pt.2

stan — Thu, 27 Oct 2011 02:26:41 +0000

Well, after looking through the details provided by dmose at the gamesaver github @ https://github.com/mozilla/gamesaver, I’ve been doing a lot of reading up on node.js, browserID, JSON, and the myfavouritebeer example. Even though the use case I’m working on sounds quite simple (user clicks on the restore button and sees the game jump to the save point), the fact that there hasn’t been really any work done on GameSaver poses quite a challenge – I don’t even know where to start! I’m going to have to have a nice talk with jbuckley or dmose to get some direction.

Working on GameSaver

stan — Tue, 25 Oct 2011 21:04:03 +0000

Okay, it’s been far too long since I blogged – just been far too busy with coursework! I talked to Jon Buckley to contribute to the paladin project and now I’m working on GameSaver, which is a server to save games as JSON blobs using browserid for identification. The ticket/story i’m working on is here…

got lots to learn again..

0.1 release of oStatus plugin for Popcorn.js

stan — Fri, 30 Sep 2011 02:17:15 +0000

Well, it’s been a rough but enlightening journey so far getting to work on bug #334 for popcorn.js. After finally getting a basic understanding of how plugins were implemented in popcorn, and how the Status.Net javascript API worked, I was able to flesh out and code a basic oStatus plugin that is able to create the three social widgets that the Status.Net javascript API currently supports.

Unfortunately I have not been able to test my plugin outside of running the popcorn test suite (which it passed, thankfully) as I believe I require a functional, installed instance of Status.Net to do so – I created an account at http://identi.ca/nm486 in hopes of testing my plugin against it, but the Status.Net wiki is cryptic and incomplete at best so I couldn’t figure out how to do so. The instructions on creating social media widgets are much clearer for a locally installed instance of Status.Net, so I’m currently installing an instance on a server I have and hopefully I can begin writing up some unit tests for my plugin in earnest soon.

I’m also going to double check with the guys at #popcorn (and probably the Status.Net devs at #statusnet on freenode IRC) to make sure I’m on the right track since I’m having difficulty really getting into the Status.Net API. I expect 0.2 to be tested and to be more aligned with the expectations of the plugin.

The link to 0.1 is at https://github.com/nm486/popcorn-js/tree/develop/plugins/statusnet

Stanley

javascript function scope and closures & plugin progress

stan — Wed, 28 Sep 2011 23:54:40 +0000

I had a really hard time wrapping my head around how javascript handles “scope” (ie its very different from the way I learned about scope say in C, or Java) and also closures. The textbook I borrowed didn’t explain it all that well to me. I found an excellent blog post about Javascript closures was absolutely great in explaining closures at a beginner level.

…So here I am grinding away at the popcorn source code, looking at existing plugin source code as a good starting ground for my Status.Net plugin – I’m finally starting to get the idea of how plugins are implemented in popcorn. Namely, there is a plugin function within popcorn that takes in three parameters: a string containing the name of the plugin, a manifest object containing info about the plugin and configuration options (n the form of an associative array), and lastly the plugin declaration itself. The declaration takes the form of a function which accepts the options array, and using the options toggled in the options array, does whatever it needs to do to create a new HTML element where all the magic happens.

Now I’m going through the Status.Net API at http://status.net/wiki/Install_the_JavaScript_API_Plugin to see what I need to do to get Status.Net plugins to display in the HTML element, then I need to start working that in to my popcorn plugin.