0
1
00:00:00,420 --> 00:00:06,480
So in the last few lessons, we looked at implementing source control locally using the command line, as
1

2
00:00:06,480 --> 00:00:10,550
well as using Xcode and, also, remotely using GitHub.
2

3
00:00:10,800 --> 00:00:17,520
So, now I want to take you a little bit further and I want to talk about collaboration using remote repositories
3

4
00:00:17,640 --> 00:00:25,800
and GitHub, because this is one of the best ways to start working in a team of programmers and to contribute
4

5
00:00:26,070 --> 00:00:28,670
your skills to open source projects.
5

6
00:00:28,680 --> 00:00:34,560
So we've seen all of these four areas: the working directory, the staging area, the local repository, as
6

7
00:00:34,560 --> 00:00:36,300
well as the remote repository.
7

8
00:00:36,480 --> 00:00:40,120
And you should be pretty familiar with all four of these areas by now.
8

9
00:00:40,380 --> 00:00:48,400
Now, in the next scenario, let's shift over to just look at the local and remote repository that you own.
9

10
00:00:48,420 --> 00:00:50,610
So let's say that Angela,
10

11
00:00:50,610 --> 00:00:57,750
so myself, I own this repository. I created it locally, and then I pushed it to my remote repository on
11

12
00:00:57,750 --> 00:00:58,890
GitHub.
12

13
00:00:58,890 --> 00:01:04,330
Now, let's say that I have an evil twin who's called,
13

14
00:01:04,730 --> 00:01:07,210
I don't know, Bad-ngela. That's a terrible name.
14

15
00:01:07,380 --> 00:01:12,150
Let's say that she also wanted to make changes to my repository.
15

16
00:01:12,150 --> 00:01:18,840
She's looking at my code base and, you know, she wants to add some features or fix some bugs or do something.
16

17
00:01:19,350 --> 00:01:27,600
Now, because I own this remote repository over here, in order for her to work on it, she could make a copy
17

18
00:01:27,600 --> 00:01:30,770
of it that exists on her GitHub account.
18

19
00:01:30,990 --> 00:01:38,550
So remember, this is different from git clone. Git clone is just grabbing the entirety of the repository,
19

20
00:01:39,060 --> 00:01:42,660
and then cloning it to your local work environment.
20

21
00:01:42,660 --> 00:01:48,360
Now, in this case, we're basically just copying a repository that's hosted on GitHub and we're keeping
21

22
00:01:48,360 --> 00:01:52,790
the copy under our own GitHub account where we can make changes to it.
22

23
00:01:53,070 --> 00:01:56,920
So this in terms of GitHub lingo is called forking.
23

24
00:01:57,030 --> 00:02:04,350
Now, once you fork a remote repository, then you now own it. You have full permissions to do whatever
24

25
00:02:04,350 --> 00:02:07,870
it is that you like with this copy of the repository.
25

26
00:02:07,890 --> 00:02:15,000
Because as you can imagine, it would be pretty crazy if everybody could modify your source code on all
26

27
00:02:15,000 --> 00:02:21,030
of your open source repositories because, you know, it would lead to, maybe, amateurs changing all sorts
27

28
00:02:21,030 --> 00:02:28,230
of things that you don't want them to or, you know, people making features that are incompatible with
28

29
00:02:28,230 --> 00:02:29,690
what you've got already.
29

30
00:02:29,700 --> 00:02:35,430
Basically, you would only give people who you have a trusting relationship with, write access to your
30

31
00:02:35,430 --> 00:02:36,580
remote repository.
31

32
00:02:36,600 --> 00:02:43,170
So, say, if you work within a team and you're all working on a product, then everybody in the team probably
32

33
00:02:43,170 --> 00:02:49,920
has both read and write permissions on a single remote repository. And that way, they can git clone and
33

34
00:02:49,920 --> 00:02:55,750
work on it locally, and then push it and resolve any sort of conflicts that way.
34

35
00:02:55,800 --> 00:03:00,080
But you don't want anybody on the internet having those kind of permissions.
35

36
00:03:00,090 --> 00:03:04,120
So how do you implement this kind of open source collaboration then?
36

37
00:03:04,140 --> 00:03:07,570
Well, it's through forking and making pull requests.
37

38
00:03:07,770 --> 00:03:12,990
So, now let's say that evil Angela, Bad-ngela has forked my repository.
38

39
00:03:13,140 --> 00:03:17,800
So on her GitHub account, she now owns a copy of my repository.
39

40
00:03:18,180 --> 00:03:24,340
And from this point, she can then clone that repository to work on it locally.
40

41
00:03:24,540 --> 00:03:31,680
And if she decides to add some features to it, maybe, you know, improve the codebase or add some more code,
41

42
00:03:31,800 --> 00:03:34,550
or do something crazy, or whatever it is that she wants,
42

43
00:03:34,690 --> 00:03:41,670
then after she's happy with that and she's committed those changes, then she can push it to her remote
43

44
00:03:41,670 --> 00:03:49,000
repository. And then if she wants me or good Angela to incorporate those changes that she made, then her
44

45
00:03:49,120 --> 00:03:56,130
only option is to make a pull request if she is not within that trusted pool of people who all have
45

46
00:03:56,130 --> 00:03:59,130
read and write access to my remote repository.
46

47
00:03:59,130 --> 00:04:05,490
So, say, if she only has read access, then she would have to make a pull request. And it's almost like making
47

48
00:04:05,520 --> 00:04:06,770
a suggestion.
48

49
00:04:06,900 --> 00:04:08,840
"Here are some suggested changes
49

50
00:04:08,850 --> 00:04:09,890
that I've been working on.
50

51
00:04:09,900 --> 00:04:16,430
What do you think about it? if you okay it, then please, you know, merge it to your remote repository."
51

52
00:04:16,740 --> 00:04:23,130
So the reason why it's called a pull request and not a push request is because the person who has the
52

53
00:04:23,130 --> 00:04:25,260
write permission to the repository,
53

54
00:04:25,290 --> 00:04:33,550
so I have write permission to my own remote repository which has been forked and duplicated by, you know,
54

55
00:04:33,930 --> 00:04:35,100
my evil twin.
55

56
00:04:35,100 --> 00:04:39,330
If she wants to incorporate those changes, then I have the deciding vote.
56

57
00:04:39,570 --> 00:04:45,270
So I can review those changes and I can pull the changes over.
57

58
00:04:45,420 --> 00:04:51,750
So it's not a push because you don't own the rights to the remote repository that you're trying to push
58

59
00:04:51,760 --> 00:04:53,070
to.
59

60
00:04:53,290 --> 00:04:59,740
In this case, if I decide after code review that, actually, those features actually added were pretty great,
60

61
00:04:59,740 --> 00:05:06,430
and it seems compatible with my code so far and doesn't break anything, then I would approve the pull
61

62
00:05:06,430 --> 00:05:12,190
request and merge her repository with my own.
62

63
00:05:12,370 --> 00:05:16,050
So the changes will be reflected in a new commit.
63

64
00:05:16,210 --> 00:05:18,330
So let's take a look at this in action.
64

65
00:05:20,060 --> 00:05:23,650
So here, we've got our original story repository.
65

66
00:05:23,690 --> 00:05:30,440
So this is a remote repository, remember, because it's hosted online on GitHub, and we've got a number
66

67
00:05:30,440 --> 00:05:37,840
of commits and we've been doing some modifications and writing to write our storyline.
67

68
00:05:37,850 --> 00:05:40,880
Now, I'm going to log out of my account.
68

69
00:05:41,060 --> 00:05:44,250
So that was the account that created the story.
69

70
00:05:44,540 --> 00:05:47,880
And then I'm going to sign in using a different account.
70

71
00:05:48,110 --> 00:05:52,220
So right now, I'm signed into a different GitHub account.
71

72
00:05:52,220 --> 00:05:55,720
This account is named gilfoyleismyothername.
72

73
00:05:55,790 --> 00:05:58,900
And now I'm going to search for that repository.
73

74
00:05:59,210 --> 00:06:03,250
So I found the story repository by the user angelabauer.
74

75
00:06:03,250 --> 00:06:05,700
So that was the one that we saw earlier on.
75

76
00:06:05,750 --> 00:06:11,960
So I'm going to go into this repository and you can see that all of these lines and files are publicly
76

77
00:06:11,960 --> 00:06:18,350
visible and you can read through all of it, even though you are now not signed in to the account that
77

78
00:06:18,350 --> 00:06:20,000
created this repository.
78

79
00:06:20,330 --> 00:06:25,760
So from here, what I'm going to do is I'm going to fork this repository.
79

80
00:06:26,360 --> 00:06:34,400
So as we mentioned before, forking is simply making a copy or a duplicate of a remote repository and
80

81
00:06:34,400 --> 00:06:40,970
putting it under your own GitHub account. So you can see this user that I've created is called
81

82
00:06:41,000 --> 00:06:42,550
gilfoyleismyothername.
82

83
00:06:42,620 --> 00:06:50,570
And now I have this repository under my own username, so I've made a copy of it, and you can see it's
83

84
00:06:50,570 --> 00:06:52,690
exactly the same as before.
84

85
00:06:52,760 --> 00:06:57,580
Everything's been copied over including all of the previous commits that were made.
85

86
00:06:57,620 --> 00:07:01,540
So, now from here, I'm going to--
86

87
00:07:01,550 --> 00:07:03,840
So from here, I'm going to make some changes.
87

88
00:07:03,890 --> 00:07:11,870
So let's maybe change one of these storylines. So let's change chapter.
88

89
00:07:14,710 --> 00:07:22,120
So let's say that this other user, this other person, has some suggested improvements to my code.
89

90
00:07:22,120 --> 00:07:28,090
or in this case, to my writing. They're still keeping the spirit of the original repository alive because
90

91
00:07:28,090 --> 00:07:33,240
we are now converting into a space theme or an alien theme.
91

92
00:07:33,700 --> 00:07:41,470
So I've made my changes to chapter4 and I'm going to commit those changes saying, "Add more space themes
92

93
00:07:43,390 --> 00:07:45,500
to chapter 4."
93

94
00:07:45,550 --> 00:07:48,590
So that's what I did, and I'm going to commit to the mast a branch.
94

95
00:07:48,610 --> 00:07:54,780
This is the master branch of my own forked copy of the story repository.
95

96
00:07:54,850 --> 00:08:02,500
So once I commit those changes, then we can view what it currently looks like under the graphs.
96

97
00:08:02,530 --> 00:08:13,310
So if we have a look at the network, you can see that this is the point where I forked the story repository.
97

98
00:08:13,520 --> 00:08:14,390
That commit
98

99
00:08:14,420 --> 00:08:20,240
was created by Angela Yu which, basically, merged this branch to the master branch.
99

100
00:08:20,240 --> 00:08:23,500
So we did that two lessons back if you remember.
100

101
00:08:23,600 --> 00:08:29,360
So the latest commit though is made by this current user, gilfoyleismyothername.
101

102
00:08:29,480 --> 00:08:37,150
And you can see that I've added it to the master branch of my forked copy of that repository.
102

103
00:08:37,190 --> 00:08:47,090
So, say, if I now open up a Incognito window and I log back in to the Angela account, and go over to that
103

104
00:08:47,180 --> 00:08:55,900
story repository, you can see that if I have a look inside my graphs, go into Network, that that latest
104

105
00:08:55,910 --> 00:08:59,650
change, it's not reflected on my master branch.
105

106
00:08:59,660 --> 00:09:05,710
It's showing up as a separate branch made by gilfoyleismyothername.
106

107
00:09:05,840 --> 00:09:09,570
And you can see the members who have forked your repository.
107

108
00:09:09,950 --> 00:09:16,850
So this is a great way of collaborating because you can have contributors make edits or add new features
108

109
00:09:17,150 --> 00:09:21,620
to your preexisting codebase or repository.
109

110
00:09:22,000 --> 00:09:30,120
And now what I can do if I head back to the Gilfoyle account, so I'm just going to flip through these
110

111
00:09:30,120 --> 00:09:37,870
two so that you can see, right now I'm inside the Gilfoyle account and this is the Angela Bauer account.
111

112
00:09:38,220 --> 00:09:45,720
So, now under the Gilfoyle account, what I can do is I can make a pull request. So we can do that
112

113
00:09:45,720 --> 00:09:46,380
here.
113

114
00:09:46,770 --> 00:09:49,050
And you can see that it's able to merge.
114

115
00:09:49,530 --> 00:09:51,540
And these are the changes,
115

116
00:09:51,570 --> 00:09:55,620
so swapping that word for that word, swapping that word for that phrase.
116

117
00:09:55,680 --> 00:10:05,170
So, now all I have to do is hit create pull request and tell the original author, which is Angela Bauer,
117

118
00:10:05,640 --> 00:10:15,120
what I've done, why I think my modifications or my features are worthy to be merged with the original
118

119
00:10:15,120 --> 00:10:16,320
repository,
119

120
00:10:16,320 --> 00:10:17,760
and, you know, any other notes,
120

121
00:10:17,760 --> 00:10:18,000
right?
121

122
00:10:18,000 --> 00:10:20,590
Any other comments that I have.
122

123
00:10:20,730 --> 00:10:21,750
Let's just say--
123

124
00:10:25,420 --> 00:10:26,890
Always helps to give complimentary.
124

125
00:10:26,890 --> 00:10:30,830
So, now let's go ahead and create a pull request.
125

126
00:10:33,560 --> 00:10:35,640
So the pull request is done.
126

127
00:10:35,700 --> 00:10:45,040
But if we have a look back into the story repository, you can see that those changes are not made, right?
127

128
00:10:45,060 --> 00:10:47,510
It's because I don't own this repository.
128

129
00:10:47,520 --> 00:10:49,050
I don't have write access.
129

130
00:10:49,050 --> 00:10:56,910
I only have read access as a member of the general public and not a member of the trusted inner circle.
130

131
00:10:57,240 --> 00:11:01,140
So I can only suggest my changes.
131

132
00:11:01,290 --> 00:11:07,530
Now, if we head over back to the Angela Bauer account, who owns this repository,
132

133
00:11:08,100 --> 00:11:14,360
now if I have a look under pull requests, I've got a brand-new pull request, right?
133

134
00:11:14,460 --> 00:11:15,820
So it previously was zero,
134

135
00:11:15,840 --> 00:11:23,900
but now I have one, and it's showing as one open pull request. And this is added a minute ago by Gilfoyle.
135

136
00:11:24,180 --> 00:11:32,300
And if I look at it, I can see why he thinks that this modification is necessary and what were his commit
136

137
00:11:32,340 --> 00:11:33,100
message,
137

138
00:11:33,360 --> 00:11:40,320
and I can also take a look at the commits that he made and compare the differences.
138

139
00:11:40,350 --> 00:11:42,780
So review those changes.
139

140
00:11:47,740 --> 00:11:49,440
So I could say something like,
140

141
00:11:49,450 --> 00:11:51,660
"Great job.
141

142
00:11:51,890 --> 00:11:53,100
"Great job,
142

143
00:11:54,290 --> 00:12:01,390
Gilfoyle." And I can submit this feedback to Gilfoyle and approve merging these changes.
143

144
00:12:03,800 --> 00:12:16,250
So, now all I have to do is hit merge pull request, and maybe add a "Merged from Gilfoyle's modifications
144

145
00:12:16,580 --> 00:12:18,930
to chapter 4."
145

146
00:12:19,340 --> 00:12:23,590
Okay, so let's go ahead and confirm the merge.
146

147
00:12:23,880 --> 00:12:30,010
And now you can see that that commit is added to Angela Bauer master.
147

148
00:12:30,030 --> 00:12:32,470
So if I have a look inside my graphs
148

149
00:12:32,470 --> 00:12:32,970
now,
149

150
00:12:35,760 --> 00:12:42,570
you can see that the latest commit was my merge and it was--and you can see where it came from. It came
150

151
00:12:42,570 --> 00:12:49,350
from a fork made by Gilfoyle which shows up as a separate branch, and then it got merged back into the
151

152
00:12:49,350 --> 00:12:52,080
main branch of the main repository.
152

153
00:12:52,110 --> 00:12:59,430
So some people use GitHub purely as version control for their own projects and use some of the features
153

154
00:12:59,430 --> 00:13:01,620
that we discussed in previous lessons.
154

155
00:13:01,890 --> 00:13:12,540
But there's also a huge community of awesome coders on here who have created really brilliant projects.
155

156
00:13:12,540 --> 00:13:19,860
And if you can see ways of improving it or contributing to it, then it's a great way of starting to
156

157
00:13:19,860 --> 00:13:26,250
learn how to work in a team of programmers which is a really essential skill when you're working for
157

158
00:13:26,250 --> 00:13:28,190
a startup or for a company.
158

159
00:13:28,740 --> 00:13:34,920
So for example, if we have a look at the Alamofire repository which is something that we've been using
159

160
00:13:34,920 --> 00:13:42,750
for quite a while, if you have a look at the contributions, you can see that there have been loads and
160

161
00:13:42,750 --> 00:13:49,890
loads of other users who have looked at the code and done things, you know, or made suggestions, and to
161

162
00:13:49,890 --> 00:13:55,530
steadily improve this framework that, you know, everybody else is benefiting off,
162

163
00:13:55,530 --> 00:13:56,140
right?
163

164
00:13:56,190 --> 00:14:02,760
You can see that a total of four4,300 forks have been made, and there's currently 4
164

165
00:14:02,820 --> 00:14:07,860
open pull requests, but 559 pull requests were closed.
165

166
00:14:07,920 --> 00:14:09,210
So let's have a look.
166

167
00:14:09,210 --> 00:14:16,030
So, for example, in this case, this guy updated the README to the current version,
167

168
00:14:16,050 --> 00:14:18,290
so that's obviously just editing a text file,
168

169
00:14:18,300 --> 00:14:21,720
and that's pretty much within anybody's capabilities, right?
169

170
00:14:21,930 --> 00:14:26,360
And then, it got merged by somebody who owned this repository.
170

171
00:14:26,650 --> 00:14:30,140
And you know they gave them a bit of feedback, right?
171

172
00:14:30,360 --> 00:14:36,960
But there's other things like, you know, code additions or code deletions, or modifications that people
172

173
00:14:36,960 --> 00:14:37,830
have made.
173

174
00:14:37,860 --> 00:14:46,590
So this guy made some fixes and, you know, he's documented what were the goals, what were the implementation
174

175
00:14:46,590 --> 00:14:47,360
details,
175

176
00:14:47,430 --> 00:14:49,530
what were the tests that he performed.
176

177
00:14:49,530 --> 00:14:55,360
And then the guy who owned the repository said, "Hey, just, you know, maybe one thing that you need to change,
177

178
00:14:55,440 --> 00:14:56,530
have a look in here."
178

179
00:14:56,580 --> 00:15:01,460
And then once it was changed, then it was approved and merged with the master branch.
179

180
00:15:01,710 --> 00:15:07,170
So have a look around on GitHub and see what are some of the cool projects that you could maybe get
180

181
00:15:07,170 --> 00:15:08,090
involved in.
181

182
00:15:08,310 --> 00:15:14,910
So to begin with, you know, some of these things that we've been using, for example, ProgressHUD, 
182

183
00:15:14,910 --> 00:15:15,440
right?
183

184
00:15:15,450 --> 00:15:17,910
We've been using inside Quizzler.
184

185
00:15:18,000 --> 00:15:24,300
You can actually have a look inside the code files and see, you know, what are the things that you would
185

186
00:15:24,300 --> 00:15:25,560
change about it,
186

187
00:15:25,860 --> 00:15:32,880
obviously, ProgressHUD is written in Objective-C, maybe choose one that is written in Swift. But have
187

188
00:15:32,880 --> 00:15:34,830
a look at the libraries that you've been using,
188

189
00:15:34,830 --> 00:15:36,060
and if you want,
189

190
00:15:36,060 --> 00:15:42,840
you can build on top of it, either for your own goals and purposes. But also, you know, if you're building
190

191
00:15:42,840 --> 00:15:48,750
on top of somebody else's open source code, then it's a nice thing to contribute back to the open source
191

192
00:15:49,230 --> 00:15:57,950
world by forking and making a pull request to offer your improvements or bug fixes, or new features.
192

193
00:15:57,960 --> 00:16:07,620
So as I said, it's almost like a social network for programmers and you can make a lot of great friends
193

194
00:16:07,620 --> 00:16:14,370
on here, and you can also get a lot of help on here in your development journey.
194

195
00:16:14,370 --> 00:16:20,010
So the last thing that I wanted to say was that in this module, I've mentioned a lot of different
195

196
00:16:20,010 --> 00:16:26,250
GitHub or Git commands and it can be quite difficult to remember all of it just by watching these videos
196

197
00:16:26,250 --> 00:16:26,960
once.
197

198
00:16:27,000 --> 00:16:33,360
So remember, you always have these videos, so you can always come back and listen to my terrible
198

199
00:16:33,420 --> 00:16:34,060
jokes,
199

200
00:16:34,140 --> 00:16:37,400
but also the information again.
200

201
00:16:37,410 --> 00:16:40,630
So you can always rewatch it and refresh yourself.
201

202
00:16:41,100 --> 00:16:51,120
But I've actually made a PDF Cheat Sheet of some of the most common Git and GitHub commands that you'll
202

203
00:16:51,150 --> 00:16:52,470
be using.
203

204
00:16:52,470 --> 00:16:58,110
And I've laid it all out in terms of arrows that we've explained before so that you'll know what I'm
204

205
00:16:58,110 --> 00:17:03,010
talking about, and you can download this PDF inside this lesson.
205

206
00:17:03,240 --> 00:17:08,450
So I hope you enjoyed all of that and I will see you on the next lesson.