Git：保留当前代码状态和​​最后四次提交

Question

请注意：这个问题与Squash my last X commits together using Git 不同，因为我们不希望将最后一个 X 提交一起压缩成一个提交 - 相反，我们希望将初始提交合并为一个提交并以自动方式保留最后四个提交/代码状态（无需手动选择提交） .

我们正在使用 git 备份/记录对文件数据存储的更改，该更改使用内部托管的 GitLab 服务器，其存储库包含一些非常大的文件。

我们想合并早期的冗余提交，这些提交不再需要减少 repo 的大小，但 保持当前代码状态和​​最后四个提交为备份以防我们需要将数据存储恢复到以前的提交。

在自动化脚本中推荐哪些命令会改变以下 git 历史记录：

0    aabbcc Initial commit
1    aabbdd First backup
2    aabbee Second backup
3    aabbff Third backup
4    aabbgg Fourth backup
5    aabbhh Fifth backup
6    aabbii Sixth backup
7    aabbjj Seventh backup (current code state)

变成以下不丢失当前代码状态：

4    aabbgg Initial commit -> Fourth backup (consolidated)
5    aabbhh Fifth backup
6    aabbii Sixth backup
7    aabbjj Seventh backup (current code state)

Answer 1

可能是这样的。

首先，压缩旧的提交：

git checkout aabbgg         # checkout the commit that you want to squash the older commits into
git reset --soft aabbcc^    # squash the commits...
git commit -m "Initial commit -> Fourth backup (consolidated)"
git tag new_base            # tag it, we will use the tag later

接下来，将较新的提交重新定位到新的基础上：

git checkout -b consolidated current_code_state
git rebase --onto new_base aabbgg

注意：为避免rebase 在冲突中停止，您可能需要指定合并策略，例如：

-s recursive -X ours -X no-renames

结果：

x - 0 - 1 - 2 - 3 - 4 - 5 - 6 - 7 (current_code_state)
 \
  4' (new_base) - 5' - 6' - 7' (consolidated)

current_code_state 和 consolidated 之间应该没有区别。

最后，如果一切顺利，删除原来的分支和之前创建的标签。

git branch -D current_code_state
git tag -d new_base

Answer 2

根据 sergej 的回答 (Git: Preserving current code state and last four commits)，我编写了一个似乎可以正常工作的自动化脚本：

#!/bin/bash

function gitConsolidation() {

    # Default settings
    numCommitsToKeep=4
    branchName="master"
    path="/home/steve/test/testgit"

    # Set working directory
    cd $path

    # Get git repo name
    gitRepoName=$(basename `git rev-parse --show-toplevel`)

    # Print default message
    echo -e "** Prepairing to consolidate current Git Repo: $gitRepoName **"
    echo -e "Branch: $branchName"
    echo -e "Path: $path"
    echo -e "Total past commits to keep: $numCommitsToKeep\n"

    # Get required branch
    git checkout $branchName

    # Get size before consolidation
    echo -e "Repo size before consolidation: $(du -hs)" 

    # Print current log list
    echo -e "\n* Git commits prior to consolidation *"  
    git log --pretty="%H - %s"

    # Get initial commit hash
    initialCommitHash=$(git rev-list --max-parents=0 HEAD)
    echo -e "\n* Found initial commit hash: $initialCommitHash *"

    # Get hash for commit to be consolidated with intiial commit
    consCommitHash=$(git log --format=%H | head -$numCommitsToKeep | tail     -1)
    echo -e "* Found hash for commit to consolidate with initial commit: $consCommitHash *"

    # Get hash for latest commit
    latestCommitHash=$(git log --format=%H | head -1)
    echo -e "* Found hash for latest commit $latestCommitHash *\n"

    # Begin consolidation
    echo -e "* BEGIN: Git repo consolidation *"

    # Checkout commit to consolidate with initial commit
    git checkout $consCommitHash

    # Soft reset initial commit
    git reset --soft $initialCommitHash

    # Commit changes
    git commit -m "Consolidated commit $initialCommitHash -> $consCommitHash"

    # Set tag
    git tag new_base

    # Checkout
    git checkout -b consolidated $latestCommitHash

    # Rebase
    git rebase --onto new_base $consCommitHash

    # Get size after consolidation
    echo -e "Repo size after consolidation: $(du -hs)"

    # Print current log list
    echo -e "\n * Git commits after consolidation *"    
    git log --pretty="%H - %s"

    echo -e "\n* END: Git repo consolidation *"
}

# Call function
gitConsolidation

已在本地测试存储库上成功运行。即将在我们的大型存储库的副本上进行测试，看看是否可以正常工作！