Git 简明教程

Git - Create Operation

在本教程中，我们将看到如何创建远程 Git 存储库；从现在起，我们将称之为 Git 服务器。我们需要 Git 服务器才能实现团队协作。

In this chapter, we will see how to create a remote Git repository; from now on, we will refer to it as Git Server. We need a Git server to allow team collaboration.

Create New User

# add new group
[root@CentOS ~]# groupadd dev

# add new user
[root@CentOS ~]# useradd -G devs -d /home/gituser -m -s /bin/bash gituser

# change password
[root@CentOS ~]# passwd gituser

上述命令将产生以下结果。

The above command will produce the following result.

Changing password for user gituser.
New password:
Retype new password:
passwd: all authentication token updated successfully.

Create a Bare Repository

让我们使用 init 命令，后面跟 --bare 选项，来初始化一个新存储库。它初始化存储库，而没有工作目录。按照惯例，裸存储库必须命名为 .git 。

Let us initialize a new repository by using init command followed by --bare option. It initializes the repository without a working directory. By convention, the bare repository must be named as .git.

[gituser@CentOS ~]$ pwd
/home/gituser

[gituser@CentOS ~]$ mkdir project.git

[gituser@CentOS ~]$ cd project.git/

[gituser@CentOS project.git]$ ls

[gituser@CentOS project.git]$ git --bare init
Initialized empty Git repository in /home/gituser-m/project.git/

[gituser@CentOS project.git]$ ls
branches config description HEAD hooks info objects refs

Generate Public/Private RSA Key Pair

让我们逐步完成配置 Git 服务器的过程， ssh-keygen 实用程序生成公钥/私钥 RSA 密钥对，我们将使用该密钥对进行用户身份验证。

Let us walk through the process of configuring a Git server, ssh-keygen utility generates public/private RSA key pair, that we will use for user authentication.

打开终端，输入以下命令，并在每个输入后面按 Enter。成功完成后，它会在主目录中创建一个 .ssh 目录。

Open a terminal and enter the following command and just press enter for each input. After successful completion, it will create a .ssh directory inside the home directory.

tom@CentOS ~]$ pwd
/home/tom

[tom@CentOS ~]$ ssh-keygen

上述命令将产生以下结果。

The above command will produce the following result.

Generating public/private rsa key pair.
Enter file in which to save the key (/home/tom/.ssh/id_rsa): Press Enter Only
Created directory '/home/tom/.ssh'.
Enter passphrase (empty for no passphrase): ---------------> Press Enter Only
Enter same passphrase again: ------------------------------> Press Enter Only
Your identification has been saved in /home/tom/.ssh/id_rsa.
Your public key has been saved in /home/tom/.ssh/id_rsa.pub.
The key fingerprint is:
df:93:8c:a1:b8:b7:67:69:3a:1f:65:e8:0e:e9:25:a1 tom@CentOS
The key's randomart image is:
+--[ RSA 2048]----+
| |
| |
| |
|
.
|
| Soo |
| o*B. |
| E = *.= |
| oo==. . |
| ..+Oo
|
+-----------------+

ssh-keygen 生成了两个密钥，第一个是私钥（即 id_rsa），第二个是公钥（即 id_rsa.pub）。

ssh-keygen has generated two keys, first one is private (i.e., id_rsa) and the second one is public (i.e., id_rsa.pub).

Note: 绝不要与其他人共享您的私人密钥。

Note: Never share your PRIVATE KEY with others.

Adding Keys to authorized_keys

假设有两位开发人员正在处理某个项目，他们分别是 Tom 和 Jerry。两个用户都生成了公钥。让我们了解如何使用这些密钥进行验证。

Suppose there are two developers working on a project, namely Tom and Jerry. Both users have generated public keys. Let us see how to use these keys for authentication.

Tom 使用 ssh-copy-id 命令将他的公钥添加到服务器，如下所示：

Tom added his public key to the server by using ssh-copy-id command as given below −

[tom@CentOS ~]$ pwd
/home/tom

[tom@CentOS ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub gituser@git.server.com

上述命令将产生以下结果。

The above command will produce the following result.

gituser@git.server.com's password:
Now try logging into the machine, with "ssh 'gituser@git.server.com'", and check in:
.ssh/authorized_keys
to make sure we haven't added extra keys that you weren't expecting.

同样，Jerry 使用 ssh-copy-id 命令将他的公钥添加到服务器。

Similarly, Jerry added his public key to the server by using ssh-copy-id command.

[jerry@CentOS ~]$ pwd
/home/jerry

[jerry@CentOS ~]$ ssh-copy-id -i ~/.ssh/id_rsa gituser@git.server.com

上述命令将产生以下结果。

The above command will produce the following result.

gituser@git.server.com's password:
Now try logging into the machine, with "ssh 'gituser@git.server.com'", and check in:
.ssh/authorized_keys
to make sure we haven't added extra keys that you weren't expecting.

Push Changes to the Repository

我们在服务器上创建了一个裸存储库，并允许两位用户访问。从现在起，Tom 和 Jerry 可以通过将其作为远程存储库添加的方式向存储库推送他们的更改。

We have created a bare repository on the server and allowed access for two users. From now on, Tom and Jerry can push their changes to the repository by adding it as a remote.

Git init 命令创建一个 .git 目录，以便每次从 .git/config 文件读取配置时存储有关存储库的元数据。

Git init command creates .git directory to store metadata about the repository every time it reads the configuration from the .git/config file.

Tom 创建一个新目录，添加 README 文件，并将他的更改提交作为初始提交。提交后，他通过运行 git log 命令验证提交消息。

Tom creates a new directory, adds README file, and commits his change as initial commit. After commit, he verifies the commit message by running the git log command.

[tom@CentOS ~]$ pwd
/home/tom

[tom@CentOS ~]$ mkdir tom_repo

[tom@CentOS ~]$ cd tom_repo/

[tom@CentOS tom_repo]$ git init
Initialized empty Git repository in /home/tom/tom_repo/.git/

[tom@CentOS tom_repo]$ echo 'TODO: Add contents for README' > README

[tom@CentOS tom_repo]$ git status -s
?? README

[tom@CentOS tom_repo]$ git add .

[tom@CentOS tom_repo]$ git status -s
A README

[tom@CentOS tom_repo]$ git commit -m 'Initial commit'

上述命令将产生以下结果。

The above command will produce the following result.

[master (root-commit) 19ae206] Initial commit
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 README

Tom 通过执行 git log 命令检查日志消息。

Tom checks the log message by executing the git log command.

[tom@CentOS tom_repo]$ git log

上述命令将产生以下结果。

The above command will produce the following result.

commit 19ae20683fc460db7d127cf201a1429523b0e319
Author: Tom Cat <tom@tutorialspoint.com>
Date: Wed Sep 11 07:32:56 2013 +0530

Initial commit

Tom 将他的更改提交到本地存储库。现在，是时候将更改推送到远程存储库了。但在那之前，我们必须将存储库添加为远程存储库，这是一次性操作。在此之后，他可以安全地将更改推送到远程存储库。

Tom committed his changes to the local repository. Now, it’s time to push the changes to the remote repository. But before that, we have to add the repository as a remote, this is a one-time operation. After this, he can safely push the changes to the remote repository.

Note - 默认情况下，Git 只推送至匹配的分支：对于本地侧存在的每个分支，如果那里已经存在具有相同名称的分支，则会更新远程侧。在我们的教程中，每次我们向 origin master 分支推送更改时，请根据您的要求使用适当的分支名称。

Note − By default, Git pushes only to matching branches: For every branch that exists on the local side, the remote side is updated if a branch with the same name already exists there. In our tutorials, every time we push changes to the origin master branch, use appropriate branch name according to your requirement.

[tom@CentOS tom_repo]$ git remote add origin gituser@git.server.com:project.git

[tom@CentOS tom_repo]$ git push origin master

上述命令将产生以下结果。

The above command will produce the following result.

Counting objects: 3, done.
Writing objects: 100% (3/3), 242 bytes, done.
Total 3 (delta 0), reused 0 (delta 0)
To gituser@git.server.com:project.git
* [new branch]
master −> master

现在，更改已成功提交到远程存储库。

Now, the changes are successfully committed to the remote repository.