Tag Archives: JavaScript

The Best Part of Any AngularJS Troll Post

Any time I see the latest “I Hate AngularJS and So Should You” article I always skip straight to the end because that’s the very best part of all of them. It’s the fun part where we get to hear what the author of this particular piece is going to advocate you use instead. Here are the usual suspects and my highly uncharitable response to each one:

I’m writing my own framework now

Bonus points for this one if it’s accompanied by a link to their new half formed idea on Github. It should continue getting commits for at least a couple of months.

There are literally dozens of front-end frameworks at this point, but theirs is going to be way better than any of them. Look, there’s really only one or two guys who will work on it, but they are stellar programmers. God knows they are going to do a much better job than programmers at Google, Facebook, or the likes of Yehuda Katz and Tom Dale.

TodoMVC is beginning to look like one of those four page resumes you get these days with all of the “frameworks” that they have examples for. If you don’t believe me, be sure to look at their “Labs” tab. Yes, they have so many they had to put in tabs.

Backbone.js

Ha ha ha ha ha ha ha ha hahahaha haha ha ha ha ha. Oh god. I may have hurt myself. This person is so upset about how “heavy weight” AngularJS is and “complex”. Look for lots of mentions of how things should be “minimal” and “simple” and at least one mention of how many lines of code Backbone.js is vs. the object of their derision. I figure their house looks like this:Form_Gable_House5

I did Backbone.js for two years, that’s why when I went somewhere new I put them on AngularJS instead. I really hope the people who advocate going back to Backbone.js have to work on a large team of mixed skill level developers. The unskilled ones will make a hash of any framework but what they can do with Backbone.js is just amazing.

That New Framework That You Just Heard About on Hacker News Two Weeks Ago

This is the framework from author #1 above. It’s going to solve all the ridiculous mistakes that AngularJS made and probably all of those from the other major frameworks as well at the same time. Ultimately it won’t get anymore updates, but that’s OK because it only got used on one project before our author realized it not only had as many problems as the major frameworks but many many more. Plus it gives him/her an opportunity to tweet about the abandonment of this framework and the excitement for the next new one.

Again, I council rationality

AngularJS is not perfect. I’m not about to say that it is. It has problems, over time they’ve been worked on and reduced. I’m sure if I went and picked up React/Flux/Relay/whatever (come on Facebook, give a name to your stack!) or Ember.js I’d see much the same things. Lots of great people are working on them and they have thousands of adopters. Most of the time for most projects it works pretty well.

If you’re having problems with AngularJS it may be that you need to learn more, look at some open source, maybe even pull in a mentor with more experience. Alternatively, if you’re struggling and you think you’ve put in more than enough effort, look at one of the major alternatives and see if it works better for you. I haven’t put in as much time on Ember.js but I’ve looked at Facebook’s offering and it is very different than what Google put together.

Ideas are like Legos

Want to learn about how I think? No. No, you don’t; but I’m going to tell you anyway. Every day that goes by I add to this long list of stuff which interests me. It is neat from a technical standpoint, or it allows me to do something I didn’t know how to do or didn’t want to figure out for myself, etc.

Then I let those pieces rattle around in my head until something occurs to me about how I could combine them with what I already know to make something interesting.

So here’s a brain dump of all the stuff rattling around up there right now:

Tools

  • Map/Reduce
    • pjs
  • Flow
    • NodeRed
    • NoFlo
    • dat

Browser Compatible Libraries

  • OAuth
    • hello.js
  • Encryption
    • TweetNaCl
  • QR Codes
    • qrcode.js
    • jquery.qrcode.js
  • Color
    • randomColor
  • Generate Files
    • FileSaver.js
  • Data
    • TingoDB
  • Markdown Editor
    • EpicEditor
  • Communications
    • WebRTC
    • Socket.IO
  • Genetic Algorithms
    • genetic-js
  • Game Development
    • Phaser.js

Server

  • Authentication
    • Passwordless
  • Framework
    • MEAN.IO/MEAN.JS

“That’s a mess of divergent crap you’ve got there John,” you might say; and you’d be right. But it’s kind of like looking at a huge pile of Legos. What do you see to build when you look?

I’m Open Sourcing Two AngularJS Projects

By far, the most successful open source thing I’ve done in years is the project I called airquotes. It was my first project built using AngularJS and I published it early on to give others a chance to see something finished which had been built using it other than a to-do list.

airquotes on Github

Since then I’ve built some other projects outside of my day job using AngularJS and though not particularly profitable they are diverse (to say the least) and I’ve decided I’d like to open source them as well to see if they can help people.

The first up is PaperQuik (PaperQuik.com). It’s an app which asks a few simple questions and then generates a printable sheet of paper (lined, dot paper, graph paper, etc.) in the browser. Unlike most sites like this, it doesn’t just have a canned set of PDF files it dispenses, nor does it have a server process building them. Instead it uses the HTML5 canvas to draw an image of the paper and then helps you print that image.

PaperQuik on Github

The second project is ClearAndDraw (ClearAndDraw.com). It’s a simple webapp that I threw together in just a few evenings because I wanted to keep track of my cards and dice for the game Marvel Dicemasters: Avengers vs. X-Men. It’s not nearly as complicated as the paper generation in PaperQuik, but it does show real time filtering using AngularJS and it stores all of the information you give it in localStorage of the user’s browser so it doesn’t forget anything they enter.

ClearAndDraw on Github

Neither of these projects has any back-end at all, they are served up strictly as a set of static HTML, CSS, JavaScript, and images and do all of their work client side. That’s not to say that I don’t want to build a back-end; ClearAndDraw.com in particular cries out for one to be added so users can enter in card/dice information and then retrieve it from any browser and any machine, rather than always having to return to the same place previous cataloging was done. But the initial solution was simple and worked as a starting point. It also presents an example of how a site might save data locally even for unregistered users and then later save that to a back-end data store if the user does create an account later.

I also took an evening and updated airquotes to the current version of AngularJS (1.2.25) and deployed it to a GitHub page so people can play with it without having to deploy it locally (like PaperQuik and ClearAndDraw).

A couple of alternative ways of data preloading in AngularJS

Gabe Scholz recently wrote the blog post: Frictionless data preloading in AngularJS If you want to skip my explanation and go straight to the code, here’s my version of the same idea: http://plnkr.co/edit/23u3BI?p=preview I’ll be honest, I wasn’t in love with the solution presented in the blog post. We don’t actually do preloading for our work at my current employer, we just load the page and do one (or many) calls to populate the page. But even so, I’ve still given the idea of preloading some thought and all of the solutions which were presented in this article left me thinking that they didn’t make good enough use of the built in object creation and injection capabilities built into AngularJS itself. So, if you check out my solution you’ll see that I create an AngularJS constant object (with examples of that created in either the index.html file or one of the JavaScript files, depending upon your preference) or I create an AngularJS service which returns a promise which is resolved with the data immediately. The latter solution has the advantage of working well if you find yourself wanting to sometimes pull from a service, sometimes use canned data, or even sometimes pull from a cache like localStorage in the browser. By separating it out to another object which is simply injected into the controller, you’ll have lots of options of how you want to inject your data and you don’t have to create any new directives to do it.

Why we abandoned server generated web pages

1. You’re constantly transporting state back and forth between client and server (and often neglecting to do so).

The next time you’re in GMail, notice something interesting about selecting emails. If you check several emails for a mass operation and then realize you’re not altogether sure about one email, so you click to read it, then you come back out to the list, the same emails are still checked. Now do the same test in an app written in any of the classic Java, PHP, Python, etc. frameworks. In those, when the user clicks on the email to view it:

  1. In all likelihood it was just a link so all of the client-side state (the checked and unchecked checkboxes) is immediately discarded by the browser.
  2. Some “clever” frameworks make that link not really a link, instead, they generate JavaScript client side which invokes a POST (as if a form was submitted), the checkboxes do get submitted to the server, stored somewhere in the user’s session, and then hopefully sent back down with the next request for the page that had the original list of checkboxes. Our links aren’t really links, there’s lots of JavaScript magic going on behind the scenes that most people you work with don’t even begin to understand and, trust me, trust me when I say this… It breaks. And it breaks badly.

2. It’s slow, slow, and did I mention slow?

  1. The development cycle itself is slower. I can throw up a temporary API using a variety of tools (or mock it client side using something like $httpBackend) and start work on the UI immediately. As I make each change I just have to refresh the browser to see my change in place. In fact, if I use tools like the Grunt server the browser refresh is automatically triggered when I save a changed file so I can just glance over at it and evaluate the results without leaving my code.

    Most server side frameworks involve a compilation step of some type (for example, Java’s JSPs are translated to servlets and then those are compiled to a byte code for the VM). Thus I have a longer wait to view each change I make.

  2. If my UI is built client-side with HTML, CSS, and JavaScript then it’s way more efficient because the only data which is being transported back and forth is that sent via the API calls to the server. I don’t have to ship a complete list of all the products wrapped in HTML layout one minute, and then minutes later what is effectively the exact same list (minus one or two and plus one or two) again wrapped in a bunch of HTML formatting. Note: Some of this can carry over to content delivery networks as well because an all static files front-end works really well around the world.
  3. Users get tired of every thing they click upon meaning another trip to the server. If they just looked at that data a minute ago, it may well be in memory locally so showing it again is free. But if I have to go to the server again to get it re-rendered for re-display, I can get really old fast. I think we can all point to a site where we are frequently frustrated by the slow performance.
  4. And why is it slow? Well, because it’s not just persisting data and performing queries on it, it’s also combining that data with HTML templates of some flavor to generate full pages and doing so over and over and over again. More work for the server means more servers needed, more time spent on performance tuning, etc.

3. It’s a more complicated programming model.

  1. If you do a lot of web applications where the pages don’t use any JavaScript to pull data on the fly, validate user’s forms in real time, etc. then that’s great. But if you are then you’ve got a wonderful hybrid going where sometimes you work in one language server side but you also use JavaScript client-side and you’ve got two different models just for one UI.
  2. For many frameworks, lots of middle tier complexity can leak into the pages, making them way more complicated than HTML and thus much harder for designers (and programmers) to work on. I’ve seen this most often in frameworks where designers are expected not to use standard HTML. Instead they’re supposed to use perfect XML where every tag perfectly matches a closing tag and not a bracket is out of place, or they can’t use the <a>, <form>, <input>, etc. tags, instead each has some replacement which is supposed to be used which typically functions about 70% or so the same as the regular tag.
  3. I loved this recent quote about JSF, a technology that I rejected at a previous employer because it was very clear that it was designed by committee and not extracted from real projects (like say Ruby on Rails):

4. Debugging is much more complicated.

Something as simple as how some HTML is rendering may require me to setup a debugger on a server on a remote machine because it is being generated from an intermediate file and data on the server.

With AngularJS or similar JavaScript frameworks, I can first look to see if the data came to the browser without problems. That involves just looking at the JSON I received from my API calls. If that’s good then I can set breakpoints in the JavaScript in the browser to see how the JavaScript code flow is going awry. On data flowing from client to server I can usually just consult the browser to see what was sent and I again know whether I’m looking at a client or server problem.

Software Rants

Mine is not a real software rant, I wrote it tongue-in-cheek after reading one just this week which spun up a bunch of people. Like most of the others, I skipped gracefully past some problems:

  • I still have non-API uses for servers. If I need a CSV or XLS file for download, it’s still way easier to have that generated on the server than to try and craft it client side with JavaScript.
  • I glossed over areas where the server generated web pages have advantages (for example, if your users are developmentally disabled and insist on staying on IE 7 or keeping JavaScript turned off).
  • I also skipped over the fact that there are browsers like older versions of IE where the debuggers are very poor and debugging can be just as painful client-side as it is for server-side.

Every framework that has achieved some level of popularity or notoriety has had its share of famous rants (Rails is a Ghetto, Node.js is stupid, and if you use it, so are you!, Why we left AngularJS which has since been renamed to 5 surprisingly painful things about client-side JS). Somebody doesn’t like the language, the framework, the community which goes with it and in frustration they vent. Sometimes they’re right about their complaints and sometimes they’re wrong, often it’s somewhere in between. Just relax and try to read it with an eye to whether the points being made are good ones and ignore the vitriol.

“selfhelp” – a self-upgrading Node.js application

I have a strange little project I’ve been working on over the last few weeks. It’s an example app I wrote using Node.js which is capable of self-upgrading itself to new versions. Thus you could use it as the basis of a cross-platform application with a browser based UI like SABnzbd+, the Plex Media Server, Couch Potato, and Sick Beard. All of which work on different operating systems (Mac OS X, Windows, and Linux) and which offer the same UI across all of them. So, this isn’t really intended for use on servers as much as it is intended for use on desktop machines so you can build apps using Node.js and whatever front-end technologies you happen to fancy (my particular flavor is AngularJS, though there is none in the example application).

I got it to where it works well on Mac OS X so I thought I’d write about it and maybe someone else would find it interesting enough to see if they could add a Windows batch file to it, maybe test it on Linux, or see if it suits a project they have been wanting to build. It’s called “selfhelp” and it’s available over on Github:

https://github.com/JohnMunsch/selfhelp

6 Tips for building JavaScript apps

I’ve actually built a few JavaScript applications in the new style (AngularJS, Backbone.js, or other front-end JavaScript framework on the front-end and only APIs on the back-end) over the last couple of years. Here are some tips on what I think has worked well on those projects:

  1. Understand this, above all else, the front-end code is not real security! If you’re an American you can understand this via an analogy. The JavaScript code running in the browser is the TSA, it is security theater which exists just to make some user’s experience better. For example, it might hide buttons which the user is not allowed to click. But that doesn’t mean that the user cannot hack the JavaScript to turn on the forbidden button anyway. All of the real security in your application exists at the API layer. It must check every single value passed to it and confirm that the user has the permissions to perform the action he/she is trying to perform before actually doing anything. Likewise, it must not return any information which the logged in user should not have access to. Relying on the JavaScript code to hide part of the data will not work. Put all of your security focus on having a bulletproof API and you will never have real security problems.
  2. People use HTTP error codes to communicate back data for their APIs. In my opinion that’s a really bad idea and often not very adaptable to the actual errors you’re having. Instead use the JSend protocol for all the JSON you return. It’s the same objects you would probably send back today except that it is wrapped with an object that tells you status (‘success’, ‘fail’, or ‘error’) and messages/codes when appropriate because there were errors. Going this route will simplify your JavaScript service calling code and help you differentiate API errors from actual transport layer problems like servers being down or problems on the network.
  3. Don’t try to sequence operations from the front-end. I once answered a question on Stack Overflow where the asker wanted to know about how to sequence a seven step process for paying for something. I answered it once telling how to do it and then again to say never to do that. You should not have your front-end be the conductor and the back-end be the orchestra. If you do, you will be sorry because eventually someone will lose their web connection, close their laptop, or just shut down their browser in the middle of your carefully choreographed sequence. Instead, always try to make API calls from front to back that provide complete units of work, complete transactions with all the information needed for multi-step operations so you won’t end up with only part of an operation completing.
  4. Please, please, please, please don’t do things that break basic conventions in your apps. There’s no reason the user shouldn’t be able to hit the back button or the forward button. It requires very little thought to support (especially if you use modern JavaScript frameworks). Ditto bookmarks and multiple tabs. There shouldn’t be any reason I can’t copy a URL and send it to somebody else or make a bookmark of my location so I can get back to the same spot. Nevertheless, I’ve worked on so many apps over the years where these basic operations acted weird or wouldn’t work at all. Don’t be one of those apps.
  5. Spend some time thinking about what happens when the user sits on a page so long his/her session expires on the server. If you’re following suggestion two above then you can send back a standard error in your JSend and catch it in your JavaScript code. Then just prompt the user to login without ever leaving the page. Likewise, think about what happens when the user clicks on a bookmark in the browser or an email and goes to the site but is not yet logged in.
  6. Please, don’t be afraid to reject some ancient browsers. There’s good code out there to help you do it and make it look nice, but ultimately you’re doing yourself, your users, and everybody else a service if you refuse service for IE 6/7/8 and maybe more than that depending upon your needs.