1 00:00:02,810 --> 00:00:08,320 Havior one Mark Price your dead slopes dot com and today we're going to talk about version control specifically 2 00:00:08,380 --> 00:00:09,640 about get. 3 00:00:09,910 --> 00:00:12,770 So let's get started. 4 00:00:12,850 --> 00:00:18,820 What I'm going to show you is kind of how version control works and I want to give you a tip from now 5 00:00:18,820 --> 00:00:24,010 on in here into the far future as your development career progresses. 6 00:00:24,220 --> 00:00:28,890 If you are not using version control on every single project you are doing it wrong. 7 00:00:28,990 --> 00:00:33,790 OK I don't want to ever see you creating a project that doesn't have version control in some form or 8 00:00:33,790 --> 00:00:34,320 fashion. 9 00:00:34,410 --> 00:00:34,700 OK. 10 00:00:34,720 --> 00:00:35,460 That is the law. 11 00:00:35,470 --> 00:00:37,480 Put it in right now in your brain. 12 00:00:37,540 --> 00:00:39,810 Always always always use version control. 13 00:00:39,990 --> 00:00:40,720 OK. 14 00:00:41,320 --> 00:00:44,170 Not to be confused with birth control or things like that. 15 00:00:44,170 --> 00:00:46,470 This is actually really important. 16 00:00:46,720 --> 00:00:50,250 So what is version control. 17 00:00:50,580 --> 00:00:52,120 Well let's talk about code here. 18 00:00:52,120 --> 00:00:56,110 OK so you write code and it creates programs. 19 00:00:56,170 --> 00:00:58,000 So let's talk about a document. 20 00:00:58,090 --> 00:00:59,620 Let's say we've got this document here. 21 00:00:59,710 --> 00:01:00,180 OK. 22 00:01:00,220 --> 00:01:01,380 It's an ugly document. 23 00:01:01,450 --> 00:01:02,380 It's OK. 24 00:01:02,860 --> 00:01:04,370 This is your document. 25 00:01:04,910 --> 00:01:09,820 OK you've written some code on it and actually it doesn't you have to be code it could be anything could 26 00:01:09,820 --> 00:01:12,600 be a text or whatever but we're going to talk about code. 27 00:01:12,610 --> 00:01:14,420 So you've written some code here. 28 00:01:14,630 --> 00:01:15,430 OK. 29 00:01:15,850 --> 00:01:19,810 Now if you're only one person and if you're working by yourself that's fine. 30 00:01:19,960 --> 00:01:23,640 You keep making changes to this and no one cares right. 31 00:01:23,650 --> 00:01:29,920 You can just keep adding and changing it all that you want how ever what happens if maybe somewhere 32 00:01:29,950 --> 00:01:30,730 right here. 33 00:01:30,880 --> 00:01:32,350 You broke something. 34 00:01:32,590 --> 00:01:33,450 OK. 35 00:01:33,880 --> 00:01:41,250 And then now your 5000 lines later today 5000 lines later of code and you just realized you had a big 36 00:01:41,290 --> 00:01:41,940 bug. 37 00:01:42,280 --> 00:01:42,940 OK. 38 00:01:43,300 --> 00:01:47,170 Well now you have to dig through 5000 lines of new code to go back and find this code here. 39 00:01:47,170 --> 00:01:48,230 So this is a problem. 40 00:01:48,280 --> 00:01:51,580 You've just done a lot of work and now you're going to have to do a lot more work to find this bug and 41 00:01:51,580 --> 00:01:52,320 go back. 42 00:01:52,510 --> 00:01:53,170 OK. 43 00:01:53,380 --> 00:01:54,310 This is one problem. 44 00:01:54,310 --> 00:01:57,450 Version control can solve and I'll tell you how to solve it in a second. 45 00:01:57,700 --> 00:01:59,160 Here's the next problem. 46 00:01:59,320 --> 00:02:03,870 OK you've got a few people let's just say to people happy Sam here. 47 00:02:03,970 --> 00:02:04,440 OK. 48 00:02:04,600 --> 00:02:05,940 That's happy Sam. 49 00:02:06,040 --> 00:02:13,110 And this one is beady eyed puppy and he's never really happy. 50 00:02:13,350 --> 00:02:13,980 OK. 51 00:02:14,260 --> 00:02:19,670 So you've got two people here this is Pete this is Sam and they've got their own code files right. 52 00:02:20,230 --> 00:02:22,370 But they're working on the same project. 53 00:02:23,100 --> 00:02:23,770 OK. 54 00:02:24,010 --> 00:02:28,140 So let's say that Sam wants to make some changes to the codebase. 55 00:02:28,310 --> 00:02:30,510 OK so he he makes changes. 56 00:02:30,580 --> 00:02:30,850 OK. 57 00:02:30,850 --> 00:02:33,390 And then Pete makes his own changes. 58 00:02:33,400 --> 00:02:34,020 OK. 59 00:02:34,240 --> 00:02:38,350 Now here's the question this is the same project or building an app together. 60 00:02:38,350 --> 00:02:41,240 How does Sam get his changes over to Pete. 61 00:02:41,950 --> 00:02:44,550 He's made one two three changes and now he's mid-twentieth you change. 62 00:02:44,560 --> 00:02:45,770 Well sounds like OK. 63 00:02:46,090 --> 00:02:50,340 Let's go ahead and load up Dropbox so you know Dropbox maybe you've done this before. 64 00:02:50,350 --> 00:02:51,210 So Dropbox. 65 00:02:51,220 --> 00:02:53,320 And then he handed over to me. 66 00:02:53,320 --> 00:02:54,960 He's like I made some changes. 67 00:02:55,000 --> 00:02:58,720 So Pete now has a new code file so he then opens up the code file. 68 00:02:58,720 --> 00:03:01,380 So he he opens up this code file here. 69 00:03:01,960 --> 00:03:06,100 And then what he does is he grabs the changes he finds all the changes that were made and then he puts 70 00:03:06,100 --> 00:03:07,400 them here in his code. 71 00:03:07,620 --> 00:03:09,460 OK. 72 00:03:09,700 --> 00:03:13,170 And he mixes them in and he's like OK I put your changes in the code now. 73 00:03:13,250 --> 00:03:18,070 Now I need to give you the latest Fosset MP sends over the combination back to Sam. 74 00:03:18,400 --> 00:03:22,000 OK here's the new file with all of Sam and peace changes in it. 75 00:03:22,030 --> 00:03:25,460 And then that's going to go ahead and overwrite this. 76 00:03:25,900 --> 00:03:31,030 And then if you've got a third person here let's say pointy nosed. 77 00:03:31,270 --> 00:03:39,470 Sally joins the project on her beedi angry eyes. 78 00:03:39,520 --> 00:03:41,240 She go up on the wrong side of the bed. 79 00:03:41,410 --> 00:03:43,300 So she now joins the project. 80 00:03:43,510 --> 00:03:49,990 So now you've got people transferring code K to all the different players on the team. 81 00:03:49,990 --> 00:03:51,650 Does that make sense. 82 00:03:51,680 --> 00:03:52,700 We've got this big mess. 83 00:03:52,720 --> 00:03:53,920 Who has the latest version. 84 00:03:53,930 --> 00:03:54,680 Blah blah blah blah. 85 00:03:54,680 --> 00:03:57,930 That's that's how it used to be a long time ago a long time ago. 86 00:03:58,090 --> 00:03:59,570 Do you think that's effective. 87 00:03:59,790 --> 00:04:01,170 Oh that's terrible. 88 00:04:01,180 --> 00:04:02,340 This is all bad. 89 00:04:02,440 --> 00:04:05,720 KATE PLUS it's you're manually taking these changes inserting them. 90 00:04:05,760 --> 00:04:06,880 Oh it's nasty. 91 00:04:06,890 --> 00:04:08,710 So this is not what we want to do. 92 00:04:08,710 --> 00:04:15,220 Problem one is saving your files if you have problems going back and be unable to revert and find those 93 00:04:15,220 --> 00:04:20,210 issues and then you've got this whole issue here with multiple people on the same team. 94 00:04:20,590 --> 00:04:24,650 Thus version control was created. 95 00:04:24,810 --> 00:04:25,530 OK. 96 00:04:25,540 --> 00:04:31,040 And what version of control is the controlling of versions of documents. 97 00:04:31,270 --> 00:04:32,210 OK. 98 00:04:32,470 --> 00:04:38,220 So let's talk about scenario one with your code backup files if someone has used a version control. 99 00:04:38,230 --> 00:04:40,940 Let's go back to Scenario 1 so make a new person here. 100 00:04:41,020 --> 00:04:42,210 Keep it interesting. 101 00:04:42,220 --> 00:04:46,910 This is Jerry and Jerry has code. 102 00:04:47,030 --> 00:04:49,520 And now let's say Jerry's using version control. 103 00:04:49,720 --> 00:04:57,180 So he makes change one day to his document and it's saved changed to it's saved. 104 00:04:57,400 --> 00:04:59,550 And we're going to call these actual commits. 105 00:04:59,560 --> 00:05:01,300 That's the that's the phrase that you'll use. 106 00:05:01,350 --> 00:05:05,970 With version control especially in regards to get so he's making comments right. 107 00:05:05,970 --> 00:05:11,850 So he's committing So what he's doing is every time he's making a change he's now committing to version 108 00:05:11,850 --> 00:05:12,630 control. 109 00:05:12,760 --> 00:05:18,480 It's being committed Now let's say he comes to version for and he finds a bug here it's like oh my gosh 110 00:05:18,870 --> 00:05:20,030 what's going on here. 111 00:05:20,220 --> 00:05:23,620 Well now what he can do is he can go check out. 112 00:05:23,880 --> 00:05:25,250 It's called checking out. 113 00:05:25,410 --> 00:05:27,740 You know like when you're checking out a girl. 114 00:05:28,470 --> 00:05:30,160 Whatever. 115 00:05:30,480 --> 00:05:33,030 Except in this case you're checking out code. 116 00:05:33,240 --> 00:05:34,360 Not really related. 117 00:05:34,360 --> 00:05:39,270 Anyway he's checking out where he wants to check out a previous commit because he wants to locate worst 118 00:05:39,300 --> 00:05:41,690 problem is what he can do is he can actually check out. 119 00:05:41,820 --> 00:05:47,400 Let's say right here number three and then he can run his code his code is restored back to that previous 120 00:05:47,400 --> 00:05:50,800 version and he can say OK the bug still exists here. 121 00:05:50,940 --> 00:05:52,220 So that is not it happened. 122 00:05:52,230 --> 00:05:57,900 And then he can check out another one another previous commit and he's like OK the bug is gone here. 123 00:05:57,900 --> 00:06:03,900 So then what he can do is he can analyze the differences between those two cochain does he doesn't have 124 00:06:03,900 --> 00:06:08,040 to go back to the five thousand lines of code if I were the problem is he can analyze it between the 125 00:06:08,040 --> 00:06:11,770 last two changes there where his problem was and let's say that it was a small problem. 126 00:06:11,850 --> 00:06:13,220 Well he may not want to fix it here. 127 00:06:13,260 --> 00:06:17,070 He can go back up here but he knows where it is now and then he can go fix that problem or he could 128 00:06:17,070 --> 00:06:19,400 just take it out of this altogether. 129 00:06:19,530 --> 00:06:24,440 And then you might have cascading problems down through here but regardless the point is you can now 130 00:06:24,510 --> 00:06:28,680 easily solve his problem because he can check out previous versions of his code. 131 00:06:29,010 --> 00:06:32,250 Also this is important here besides just checking our previous code. 132 00:06:32,250 --> 00:06:34,140 This allows you to have multiple versions. 133 00:06:34,230 --> 00:06:36,140 OK multiple versions of your application. 134 00:06:36,180 --> 00:06:37,550 It's like saving backups right. 135 00:06:37,620 --> 00:06:38,310 Saving backup. 136 00:06:38,320 --> 00:06:39,660 That's what this is so this is safe. 137 00:06:39,660 --> 00:06:42,820 This is much better than the first scenario we're talking about. 138 00:06:43,010 --> 00:06:43,790 OK. 139 00:06:44,130 --> 00:06:46,970 Now let's talk about the other scenario where we have multiple people. 140 00:06:47,010 --> 00:06:47,620 OK. 141 00:06:47,770 --> 00:06:49,830 So this guy here. 142 00:06:49,980 --> 00:06:50,790 So happy. 143 00:06:50,910 --> 00:06:52,010 He loves the code. 144 00:06:52,110 --> 00:06:52,510 All right. 145 00:06:52,530 --> 00:06:54,160 And he's got his code here. 146 00:06:54,900 --> 00:06:56,320 And then let's go over here. 147 00:06:56,730 --> 00:07:03,020 And this guy's name is Sam too but this is sinister. 148 00:07:03,090 --> 00:07:09,240 Sam he plays online games and thinks is real cool but I have the handle games at his code. 149 00:07:09,270 --> 00:07:18,750 And then what we've got down here is you've got this guy and this is Harry and Harry has his own code 150 00:07:18,770 --> 00:07:21,070 to say how do we solve this problem. 151 00:07:21,090 --> 00:07:23,930 You have any ideas where does version control come into play. 152 00:07:24,000 --> 00:07:25,490 Well let's take a look at this. 153 00:07:25,500 --> 00:07:28,440 So let's say Jim mix changes 1 2 and 3. 154 00:07:29,100 --> 00:07:33,440 And since Tristan mainstreams is one two and three and let's all say Harry. 155 00:07:33,780 --> 00:07:37,760 Well Harry sucks at coding so he only made one change and it wasn't really good. 156 00:07:38,310 --> 00:07:44,240 And anyway so you've got these three these three people here i'm just had sucks Coney's practice you 157 00:07:44,250 --> 00:07:48,640 get better over time and you're like thanks for de-motivating me. 158 00:07:49,050 --> 00:07:50,220 So they've all made their changes right. 159 00:07:50,220 --> 00:07:53,080 Remember how before we had to swap documents all that kind of stuff. 160 00:07:53,080 --> 00:07:57,460 Well now what we can do is Jim can now commit. 161 00:07:57,520 --> 00:08:00,340 OK so he's made these three commits these three Kamisese treatments. 162 00:08:00,360 --> 00:08:01,990 He can push them up to a server. 163 00:08:02,130 --> 00:08:02,580 OK. 164 00:08:02,730 --> 00:08:05,530 Or some location whatever it doesn't matter it's it's arbitrary. 165 00:08:05,530 --> 00:08:10,540 The location is arbitrary but let's just call this the business call this the server for right now. 166 00:08:10,710 --> 00:08:11,210 OK. 167 00:08:11,310 --> 00:08:14,680 So what he can actually do is he can push these changes here. 168 00:08:14,940 --> 00:08:15,610 OK. 169 00:08:15,840 --> 00:08:20,180 And then what happened is that he can actually pull down those changes. 170 00:08:20,310 --> 00:08:22,880 OK so he can recall this kush. 171 00:08:22,950 --> 00:08:25,660 So Jim can push sinister Samkon. 172 00:08:25,670 --> 00:08:31,380 Paul what happens is it's going to pull those changes and what it's going to do is it's going to automatically 173 00:08:31,590 --> 00:08:36,810 inject those changes where they need to go in Sam's code automatically he's going to inject them in 174 00:08:36,810 --> 00:08:37,420 there. 175 00:08:37,590 --> 00:08:42,690 And if there's no conflict meaning if no one edited the same line of code at the same time it's called 176 00:08:42,690 --> 00:08:46,360 a merge conflict we'll talk about that later on in the lessons. 177 00:08:46,410 --> 00:08:49,990 But if you automatically inject them right in there. 178 00:08:50,430 --> 00:08:50,920 That's cool. 179 00:08:50,950 --> 00:08:51,620 Now that's Paul. 180 00:08:51,630 --> 00:08:57,000 And now with those things merge this is called Amerge so centrist that sinister stamp has now merged 181 00:08:57,390 --> 00:08:58,890 those changes merged. 182 00:08:58,920 --> 00:09:04,710 Now what he can do is he can actually push the merge back to the server so the server is now up to date 183 00:09:04,830 --> 00:09:07,340 with gyms and or stamps code. 184 00:09:07,350 --> 00:09:08,550 And now Harry. 185 00:09:08,650 --> 00:09:09,100 OK. 186 00:09:09,150 --> 00:09:11,550 He can actually pull down all of their changes. 187 00:09:11,550 --> 00:09:14,600 So he's polling and that's going to inject them all in here. 188 00:09:14,610 --> 00:09:16,070 Boom boom boom boom. 189 00:09:16,470 --> 00:09:17,120 OK. 190 00:09:17,340 --> 00:09:22,330 And then once those are merged Harry can now push all the changes back up. 191 00:09:22,350 --> 00:09:25,380 And now the server has everyone's code changes. 192 00:09:25,380 --> 00:09:28,080 No one had to swap files in to happen automatically. 193 00:09:28,080 --> 00:09:32,370 The pushing in the polling like I drew it out here but really you could literally if off if everything 194 00:09:32,370 --> 00:09:35,010 worked out the way it was you could literally make the changes. 195 00:09:35,010 --> 00:09:38,580 Pull down someone else's change just merge them in and push them back and you could do that within a 196 00:09:38,580 --> 00:09:41,950 couple of minutes for less seconds even. 197 00:09:42,060 --> 00:09:47,070 So we went from this massively crazy process of managing people's code to working automatically. 198 00:09:47,070 --> 00:09:50,760 Everyone's so happy even sinners Sam is starting to break out a smile. 199 00:09:51,010 --> 00:09:51,570 OK. 200 00:09:51,750 --> 00:09:54,750 Devious smile but because you put a bug in the code. 201 00:09:54,750 --> 00:09:55,630 But anyway. 202 00:09:55,980 --> 00:09:58,520 So version control very very powerful. 203 00:09:58,560 --> 00:09:59,080 OK. 204 00:09:59,220 --> 00:10:05,380 Never ever ever ever ever write any code any more on any project if you don't have birth control and 205 00:10:05,380 --> 00:10:10,060 of course the most popular version control system right now is called Get G-I. 206 00:10:10,090 --> 00:10:17,710 There are other systems such as mercurial perforce SVM things like that and some larger companies are 207 00:10:17,710 --> 00:10:22,630 still using those but get is blowing away the world right now it's fantastic. 208 00:10:22,780 --> 00:10:24,740 And that's what we're using in these lessons here. 209 00:10:25,030 --> 00:10:27,640 And it's not that hard. 210 00:10:27,700 --> 00:10:30,430 Even a beginner can get up and running with it fairly quick. 211 00:10:30,520 --> 00:10:38,080 So that's version control that to get started to make sense started to dig your brain wrapper around 212 00:10:38,080 --> 00:10:39,010 the concept. 213 00:10:39,040 --> 00:10:44,470 In the end what I want to think about is just imagine having multiple versions of a file and a system 214 00:10:44,470 --> 00:10:47,430 that manages that for you so you never have to copy and paste again. 215 00:10:47,560 --> 00:10:52,300 And because the more you have to do copying and pasting the more error prone your code becomes and you 216 00:10:52,300 --> 00:10:54,170 never ever want any code. 217 00:10:54,250 --> 00:10:54,760 So that's it. 218 00:10:54,760 --> 00:11:00,810 Mark Price and def slopes duck come forward and remember to get your free life help. 219 00:11:00,840 --> 00:11:05,020 Dennis Lopes dot com and click on the chat room with thousands of students and they're helping each 220 00:11:05,020 --> 00:11:05,880 other out. 221 00:11:05,890 --> 00:11:07,150 Also click on the forums. 222 00:11:07,150 --> 00:11:09,730 This is where you can search for answers to your coat problems. 223 00:11:09,730 --> 00:11:11,190 You can also post your own issues. 224 00:11:11,300 --> 00:11:12,070 So head on over now.