Adding Third-party Functionality with Gems

Quick reference

• 00:04 In this video I want to talk about adding third party functionality to your programs
• 00:08 with something called gems.
• 00:10 So one of the great things about Ruby is it has a huge community of programmers,
• 00:15 people that have been building little things that you can use for a long,
• 00:19 long time.
• 00:20 These things are called gems, and you can add them to your program.
• 00:22 It's sort of like class inheritance where you suck it in from somewhere else, and
• 00:26 you can use it, but a little bit different.
• 00:28 So they're called gems.
• 00:29 You know Ruby is a gem, so gem is like a little package that you can use.
• 00:33 It's a whole Ruby theme, I guess.
• 00:35 But to find these programs go to this website called RubyGems.org.
• 00:39 And you can see there's 14 billion downloads and counting, and
• 00:43 this is just a repository of gems that people have created that you can use
• 00:47 totally free in your program.
• 00:49 So I'm going to show you how to use these.
• 00:51 They're very easy to use, and we're going to search for
• 00:54 something called Faker, and Faker is a gem.
• 00:57 You can see it's been downloaded almost 15 million times.
• 01:00 Faker just generates random text, random stuff, fake data, right?
• 01:04 So we can play around with this.
• 01:06 But before we do, let me show you how to install these things.
• 01:09 It's a two step process.
• 01:10 You have to install the gem into your command line, and
• 01:13 then you have to pull the gem into your file.
• 01:15 So, first off, let's get rid of all this stuff.
• 01:18 And all you do is you come here to Ruby gems, and you look for the name,
• 01:22 and it's just right here.
• 01:23 This Faker, F-A-K-E-R.
• 01:25 So to install it just come to your command line, and type in gem install,
• 01:30 with spaces, and then inside the quotation marks just put the name of the gem.
• 01:35 So ours is faker, and if we hit enter you could see it's fetching the gem.
• 01:39 It's pulling it from rubygems.org, and you'll notice it says two gems installed.
• 01:44 A lot of times gems have dependencies.
• 01:46 They require other gems in order to use them, and they'll download and
• 01:49 install automatically, so it's no big deal.
• 01:51 So now this gem is installed in our system here, our C9 system, and
• 01:55 we can go ahead and use it by simply referencing it at the top of our program.
• 01:59 So I'm just going to go require, and then faker, and that's it.
• 02:04 Now we can use this gem.
• 02:05 So let's come over here and see what this gem is all about.
• 02:08 We can usually either look at the documentation or the homepage.
• 02:12 I'm going to go to the homepage, and
• 02:14 if we scroll down here this is all the stuff that Faker will do.
• 02:17 It will create fake data about Dragon Ball, food, friends, Game of Thrones,
• 02:21 Harry Potter, Hitchhiker's Guide to the Galaxy, all these different things,
• 02:25 Lord of the Rings.
• 02:26 And you can click through here and kind of look at this and read about this.
• 02:28 Some of this stuff is hilarious.
• 02:30 Let's look at this one.
• 02:31 Chuck Norris.
• 02:31 This will create a fake Chuck Norris fact.
• 02:35 So to use this all we have to do is grab this line, copy it, and
• 02:39 bring it back to our program, and let's say puts Faker: :ChuckNorris.fact.
• 02:45 Save this guy, run the program.
• 02:48 The only pattern Chuck Norris knows is God Object.
• 02:51 I have no idea what that means.
• 02:53 Let's run it again.
• 02:53 Chuck Norris' protocol design method has no status, requests or responses,
• 02:58 only commands.
• 02:58 I don't know what that means either.
• 03:00 So that's a Chuck Norris fact.
• 03:02 If we come back here, another one I kind of like Is, there we go,
• 03:06 Company, and then Company.bs.
• 03:09 I like this one, so let's try this one.
• 03:11 We just paste this in there, just save it, hit reload.
• 03:14 Revolutionize compelling solutions, seize enterprise technologies.
• 03:20 Weird business catchphrases, drive wireless portals.
• 03:24 Love it.
• 03:24 So it's just that easy to add functionality,
• 03:27 add these little programs to your program.
• 03:30 We could also say my variable equals, and
• 03:34 then puts out my VAR like that.
• 03:38 Once these things are in your program you can do anything you want with them, and
• 03:41 it's just that easy.
• 03:42 So come over here to rubygems, look around for different gem, I mean,
• 03:46 there's millions of gems that you can use.
• 03:48 They're all free.
• 03:49 You have to do a little searching to find,
• 03:51 there's some guides that can tell you more about this stuff.
• 03:54 Play around with this faker gem.
• 03:55 It's a lot of fun.
• 03:56 All kinds of weird stuff that you can do with it.
• 03:58 Just come through here, and just click on these things, and start reading.
• 04:01 How I Met Your Mother.
• 04:03 So just good stuff.
• 04:04 So that's all for this video.
• 04:06 In the next video we're going to start putting everything we've learned together,
• 04:09 and we're going to build a neat, little math flash card game.
• 04:12 A little app.
• 04:12 And so that'll be in the next video.

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