Git Tutorials/Creating and Changing Repositories - Revision history

Kamil-braschke-0d3e@uni-wuppertal.de at 12:56, 31 August 2022

2022-08-31T12:56:24Z

Kamil-braschke-0d3e@uni-wuppertal.de at 11:34, 30 August 2022

2022-08-30T11:34:55Z

Kamil-braschke-0d3e@uni-wuppertal.de at 14:08, 24 August 2022

2022-08-24T14:08:08Z

Kamil-braschke-0d3e@uni-wuppertal.de: /* Using a remote Repository */

2022-08-18T13:28:17Z

Using a remote Repository

Kamil-braschke-0d3e@uni-wuppertal.de at 12:36, 3 August 2022

2022-08-03T12:36:51Z

Kamil-braschke-0d3e@uni-wuppertal.de at 11:38, 3 August 2022

2022-08-03T11:38:42Z

Show changes

Kamil-braschke-0d3e@uni-wuppertal.de at 09:39, 3 August 2022

2022-08-03T09:39:01Z

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Kamil-braschke-0d3e@uni-wuppertal.de: /* Useful Links */

2022-07-28T15:03:08Z

Useful Links

Kamil-braschke-0d3e@uni-wuppertal.de at 15:00, 28 July 2022

2022-07-28T15:00:45Z

Show changes

Kamil-braschke-0d3e@uni-wuppertal.de at 14:48, 27 July 2022

2022-07-27T14:48:21Z

@@ Line 156: / Line 156: @@
 </syntaxhighlight>
-This yields information about the authors who made changes to the repository, dates, related <syntaxhighlight inline>commit</syntaxhighlight> messages (lines 6 and 12) and <syntaxhighlight inline>commit</syntaxhighlight> names/references (lines 2 and 8, the string after <syntaxhighlight inline>commit </syntaxhighlight>). You can use {{Avoid wrap|<syntaxhighlight inline>git show <commit reference></syntaxhighlight>}} for detailed information on a particular <syntaxhighlight inline>commit</syntaxhighlight>. The long reference is actually not required, and the shortened version you get with <syntaxhighlight inline>git log --oneline</syntaxhighlight> can be used instead. Remember to inspect the different options you can pass to <syntaxhighlight inline>git log</syntaxhighlight> for extended or filtered output.
+This yields information about the authors who made changes to the repository, dates, related <syntaxhighlight inline>commit</syntaxhighlight> messages (lines 6 and 12) and <syntaxhighlight inline>commit</syntaxhighlight> names/references (lines 2 and 8, the string after <syntaxhighlight inline>commit </syntaxhighlight>). These automatically generated references are the SHA-values of each <syntaxhighlight inline>commit</syntaxhighlight>. You can use {{Avoid wrap|<syntaxhighlight inline>git show <commit reference></syntaxhighlight>}} for detailed information on a particular <syntaxhighlight inline>commit</syntaxhighlight>. The long reference is actually not required, and the shortened version you get with <syntaxhighlight inline>git log --oneline</syntaxhighlight> can be used instead. Remember to inspect the different options you can pass to <syntaxhighlight inline>git log</syntaxhighlight> for extended or filtered output.
 Once you know which version you want to go back to, use the {{Avoid wrap| <syntaxhighlight inline>git checkout <commit reference> .</syntaxhighlight>}} command (with <syntaxhighlight inline>.</syntaxhighlight> at the end):

@@ Line 29: / Line 29: @@
 * You have installed [https://git-scm.com/downloads Git]
 * You have a folder (we will call it ''MyFolder''), that you want to put under revision control
-* You have set your identity and email through the two commands<syntaxhighlight>user@HPC.NRW:~$ git config --global user.name "Your Name Comes Here"
+* You have set your identity and email through the two commands
 user@HPC.NRW:~$ git config --global user.email you@yourdomain.example.com</syntaxhighlight>
 Once those conditions are met, go into ''MyFolder'' and initialize the repository by entering
-<syntaxhighlight lang="text" line>
+<syntaxhighlight lang="console" line>
 user@HPC.NRW:~$ cd MyFolder
 user@HPC.NRW:~MyFolder/$
@@ Line 42: / Line 43: @@
 Your repository has been initialized (line 4). Your box has been created, but currently it is still empty. You need to '''note''' with which content you want to fill the box/repository by using the <syntaxhighlight inline>git add</syntaxhighlight> command. You can simply '''note''' to add the whole directory with
-<syntaxhighlight>
+<syntaxhighlight lang="console">
 user@HPC.NRW:~MyFolder/$ git add .
 </syntaxhighlight>
@@ Line 48: / Line 49: @@
 If you want to '''note''' the addition of one or more particular files you can do this through
-<syntaxhighlight>
+<syntaxhighlight lang="console">
 user@HPC.NRW:~MyFolder/$ git add someFiles* andMore
 </syntaxhighlight>
@@ Line 55: / Line 56: @@
 Once you are sure what goes in, it is time to '''put''' it in the box and '''apply the changes'''. This is done through the <syntaxhighlight inline>git commit</syntaxhighlight> command. It has to be accompanied by a message, which describes the changes you have made to the repository. Using the imperative in <syntaxhighlight inline>commit</syntaxhighlight> messages is a widely suggested convention. The message can be directly written with the <syntaxhighlight inline>commit</syntaxhighlight> through the option <syntaxhighlight inline>-m</syntaxhighlight>:
-<syntaxhighlight>
+<syntaxhighlight lang="console">
 user@HPC.NRW:~MyFolder/$ git commit -m "Create repository/box and fill it with some initial files"
 </syntaxhighlight>
@@ Line 64: / Line 65: @@
 You actually already know everything you need to apply further changes to your repository/box. Let's assume you want to <syntaxhighlight inline>add</syntaxhighlight> a new file ''newFile'' to the repository and that you have also made some adjustments to the file ''andMore'', which is already inside the box. As the box is already '''created''', you only need to '''note''' what you want to add and change:
-<syntaxhighlight>
+<syntaxhighlight lang="console">
 user@HPC.NRW:~MyFolder/$ git add andMore newFile
 </syntaxhighlight>
@@ Line 70: / Line 71: @@
 Of course, you can also simply use <syntaxhighlight inline>git add .</syntaxhighlight> to '''note''' all the changes that have been made so far. Afterwards, '''put''' everything in the box and '''apply the changes''' through {{Avoid wrap|<syntaxhighlight inline>git commit -m "My commit message"</syntaxhighlight>}}. If you have not added any new files, but only made changes to existing ones, then you can type
-<syntaxhighlight>
+<syntaxhighlight lang="console">
 user@HPC.NRW:~MyFolder/$ git commit -a -m "My commit message with no new files added"
 </syntaxhighlight>
@@ Line 80: / Line 81: @@
 The easiest way to control what should not go in your repository is the <syntaxhighlight inline>.gitignore</syntaxhighlight> file. Simply create the file in your repository and note inside, what you want to exclude from revision control. If you do not want to track any <syntaxhighlight inline>.txt</syntaxhighlight> files and the <syntaxhighlight inline>logo.jpg</syntaxhighlight> file in particular, you could do the following:
-<syntaxhighlight line>
+<syntaxhighlight lang="console" line>
 user@HPC.NRW:~MyFolder/$ touch .gitignore
 user@HPC.NRW:~MyFolder/$ echo -e "*.txt\nlogo.jpg" > .gitignore
@@ Line 140: / Line 141: @@
 One advantage of revision control is the possibility of easily going back to an older version of your repository. As with every <syntaxhighlight inline>git add</syntaxhighlight> you have '''noted''' the changes made to the repository's contents, git can use these notes to switch back to a previous state/version. In order to see all existing versions, use the <syntaxhighlight inline>git log</syntaxhighlight> command:
-<syntaxhighlight lang ="text" line>
+<syntaxhighlight lang ="console" line>
 user@HPC.NRW:~MyFolder/$ git log
 commit aab2d012c5a5965d14c440a6727191c19625e6e3 (HEAD -> master)
@@ Line 158: / Line 159: @@
 Once you know which version you want to go back to, use the {{Avoid wrap| <syntaxhighlight inline>git checkout <commit reference> .</syntaxhighlight>}} command (with <syntaxhighlight inline>.</syntaxhighlight> at the end):
-<syntaxhighlight line>
+<syntaxhighlight lang="console" line>
 user@HPC.NRW:~MyFolder/$ git checkout 3076389 .
 Updated 1 path from 83ca202
@@ Line 193: / Line 194: @@
 Afterwards, you associate your local repository with your remote one and <syntaxhighlight inline>push</syntaxhighlight> your latest <syntaxhighlight inline>commit</syntaxhighlight> to GitHub's repository:
-<syntaxhighlight lang="text" line>
+<syntaxhighlight lang="console" line>
 user@HPC.NRW:~MyFolder/$ git remote add origin https://github.com/HPC.NRW-User/Wikipages.git
 user@HPC.NRW:~MyFolder/$ git branch -M main
@@ Line 220: / Line 221: @@
 [[File:Git_tutorial_-_clone_commit_push.png|thumb|500px|Figure 1: Visualization of the worklflow with different <syntaxhighlight inline>git</syntaxhighlight> operations acting on a remote and a local repository. Different colors represent different/modified content. As can be seen, it is suggested that a <syntaxhighlight inline>push</syntaxhighlight> is only performed after sufficient changes have been implemented in the local repository. However, for the local repository it is better to <syntaxhighlight inline>commit</syntaxhighlight> often.]]
-<syntaxhighlight line>
+<syntaxhighlight lang="console" line>
 user@HPC.NRW:~MyFolder/$ mkdir ~/myClonedFolder
 user@HPC.NRW:~MyFolder/$ cd ~/myClonedFolder
@@ Line 251: / Line 252: @@
 The above points correspond to the following lines:
-<syntaxhighlight lang="text" line>
+<syntaxhighlight lang="console" line>
 user@HPC.NRW:~MyFolder/$ cd ~/myClonedFolder
 user@HPC.NRW:~MyFolder/$ touch clonedRepoFile

← Older revision		Revision as of 14:08, 24 August 2022
Line 165:		Line 165:
	Please keep in mind that you should attach an appropriate message to your next <syntaxhighlight inline>commit</syntaxhighlight> to keep everybody aware of version revert due to a <syntaxhighlight inline>checkout</syntaxhighlight>. Generally, such reverts should not be done without caution, even more so when cooperating on a project. It is preferable to use branches in such cases - a [[Git_Tutorials/Branching\|topic touched later upon]].		Please keep in mind that you should attach an appropriate message to your next <syntaxhighlight inline>commit</syntaxhighlight> to keep everybody aware of version revert due to a <syntaxhighlight inline>checkout</syntaxhighlight>. Generally, such reverts should not be done without caution, even more so when cooperating on a project. It is preferable to use branches in such cases - a [[Git_Tutorials/Branching\|topic touched later upon]].

		+	{\| role="presentation" class="wikitable mw-collapsible mw-collapsed" style="background-color:white; width:54em" data-expandtext="▼" data-collapsetext="▲"
		+	\|+ style="background-color:#2e3871; color:white;text-align: center; width:10em"\| <strong>Further remarks</strong>
		+	\|-
		+	\| <syntaxhighlight inline>git reset --hard <name of commit></syntaxhighlight> can also be used to go back to a previous version and discard all changes that have been made since then.
		+	\|-
		+	\| Revert changes of a specific version, but keep other changes (that have been done afterwards) by using {{Avoid wrap\|<syntaxhighlight inline>git revert <name of commit></syntaxhighlight>}}. Internally, this does not revert files, but commits changes through which the files become identical to their reverted state.
		+	\|}

	== Using a remote Repository ==		== Using a remote Repository ==

@@ Line 209: / Line 209: @@
 The next step is to learn how you can join an existing remote repository. Usually, you have to make sure that others (or you yourself) are allowed to contribute to a remote repository and to download from it. In our case, you are the only user and therefore no further settings are required. For practicing purposes, we will continue using the current remote repository.
 The first thing you often want to do is to <syntaxhighlight inline>clone</syntaxhighlight> an existing repository, which basically means, you are going to '''create''' an empty box and '''put''' into it exactly what is in the remote repository box:
 <syntaxhighlight line>
@@ Line 225: / Line 228: @@
 </syntaxhighlight>
-That’s it. You have successfully <syntaxhighlight inline>clone</syntaxhighlight>''d'' a remote repository and can start working on it.
+That’s it. You have successfully <syntaxhighlight inline>clone</syntaxhighlight>''d'' a remote repository and can start working on it. Figure 1 visualizes how <syntaxhighlight inline>clone</syntaxhighlight>, <syntaxhighlight inline>commit</syntaxhighlight> and <syntaxhighlight inline>push</syntaxhighlight> operations affect local and remote repositories.
@@ Line 251: / Line 254: @@
 </syntaxhighlight>
 Afterwards, the contents of your folders ''myFolder'' and ''myClonedFolder'' should be identical. <syntaxhighlight inline>pull</syntaxhighlight> is most commonly used to be up-to-date with changes other contributors have <syntaxhighlight inline>push</syntaxhighlight>''ed'' and not for going back to an older version. The latter will more often than not lead to conflicts with other versions which need to be painstakingly resolved and that will propagate to future versions for your colleagues, once you have <syntaxhighlight inline>commit</syntaxhighlight>''ted'' and <syntaxhighlight inline>push</syntaxhighlight>''ed'' your changes after <syntaxhighlight inline>pull</syntaxhighlight>''ing'' an older version.
 == Best Practices ==

@@ Line 1: / Line 1: @@
 [[Category:Tutorials|Git Tutorials: Creating and Changing Repositories]]<nowiki />
 {{DISPLAYTITLE:Git Tutorial: Creating and Changing Repositories}}<nowiki />
 {{Syllabus Git Tutorials}}
@@ Line 18: / Line 18: @@
 Keep in mind that <syntaxhighlight inline>push</syntaxhighlight> and <syntaxhighlight inline>pull</syntaxhighlight> usually require additional <syntaxhighlight inline>merge</syntaxhighlight> work, which will be covered in a later tutorial. However, if you stick with this tutorial, you should be fine.
@@ Line 257: / Line 260: @@
 * <syntaxhighlight inline>checkout</syntaxhighlight> and <syntaxhighlight inline>pull</syntaxhighlight> are not meant for jumping back and forth between different versions of code. <syntaxhighlight inline>checkout</syntaxhighlight> should be used sparsely, while <syntaxhighlight inline>pull</syntaxhighlight> is intended to get your local repository up-to-date with other's contributions to the remote repository.
 * <syntaxhighlight inline>commit</syntaxhighlight> messages should be used in imperative form ("add" instead of "added" or "Write new method for..." instead of "Wrote new method for..."). However, this is just a convention.
@@ Line 272: / Line 276: @@
 * [https://lab.github.com/githubtraining/uploading-your-project-to-github Interactive GitHub course]: uploading your project to GitHub

← Older revision		Revision as of 15:03, 28 July 2022
Line 162:		Line 162:

	== Useful Links ==		== Useful Links ==
		+
		+	* [https://lab.github.com/githubtraining/uploading-your-project-to-github Interactive GitHub course]: uploading your project to GitHub

← Older revision		Revision as of 14:48, 27 July 2022
Line 48:		Line 48:
	</syntaxhighlight>		</syntaxhighlight>
	This command will be followed by information regarding your commit like the amount of files and changes it contained. At this point, it will also inform you that you have commited to your master branch. Branches will be covered later, so you do not need to worry about them.		This command will be followed by information regarding your commit like the amount of files and changes it contained. At this point, it will also inform you that you have commited to your master branch. Branches will be covered later, so you do not need to worry about them.
		+
		+	=== Modifying your repository ===
		+
		+	You actually already know everything you need to apply further changes to your repository/box. Let's assume you want to add a new file ''newFile'' to the repository and that you have also made some adjustments to the file ''andMore'', which is already inside the box. As the box is already '''created''', you only need to '''note''' what you want to add and change:
		+
		+	<syntaxhighlight line>
		+	user@HPC.NRW:~MyFolder/$ git add andMore newFile
		+	</syntaxhighlight>
		+
		+	Of course you can also simply use <syntaxhighlight inline>git add .</syntaxhighlight> to '''note''' all the changes that have been made so far. Afterwards, '''put''' everything in the box and '''apply the changes''' through <syntaxhighlight inline>git commit -m "My commit message"</syntaxhighlight>. If you have not added any new files, but only made changes to existing ones, then you can type
		+
		+	<syntaxhighlight line>
		+	user@HPC.NRW:~MyFolder/$ git commit -a -m "My commit message with no new files added"
		+	</syntaxhighlight>
		+	This will automatically perform the <syntaxhighlight inline>git add</syntaxhighlight> command on the files which have changed since your last commit (again: No new files will be added this way!).