# git

* [Learn](#learn)
* [Workflow](#workflow)
  * [commit](#commit)
  * [log](#log)
  * [branch and merge](#branch-and-merge)
  * [Undo](#undo)
  * [stashing](#stashing)
  * [remote and push](#remote-and-push)
    * [delete remote branch](#delete-remote-branch)
* [config](#config)
  * [Proxy](#proxy)
* [filter-branch](#filter-branch)
* [Remove File](#remove-file)
  * [Unpushed commit](#unpushed-commit)
  * [Every commit](#every-commit)
  * [from Github](#from-github)
* [rebase](#rebase)
* [fork](#fork)
* [Submodules](#submodules)
* [Github API](#github-api)
  * [Download by tag](#download-by-tag)
  * [curl Github](#curl-github)
  * [Query latest release](#query-latest-release)
* [Github](#github)
* [Self-host git servers](#self-host-git-servers)
* [Tools](#tools)

## Learn

* Practise: https://learngitbranching.js.org/?locale=en\_US
* Cheatsheet
  * 4 Pages: https://about.gitlab.com/images/press/git-cheat-sheet.pdf
  * 2 Pages: https://education.github.com/git-cheat-sheet-education.pdf
  * 2 Pages: https://www.atlassian.com/dam/jcr:8132028b-024f-4b6b-953e-e68fcce0c5fa/atlassian-git-cheatsheet.pdf
* Books
  * https://git-scm.com/book/en/v2

[my functions](https://github.com/fzinfz/scripts/blob/master/lib/git.sh#L1):

```bash
source /dev/stdin <<< "$(curl -sSL https://raw.githubusercontent.com/fzinfz/scripts/master/lib/git.sh)"
```

## Workflow

https://stackoverflow.com/questions/3689838/whats-the-difference-between-head-working-tree-and-index-in-git\
![](https://i.stack.imgur.com/caci5.png)

```
cat .git/HEAD       # current branch head
    ref: refs/heads/master
cat .git/ORIG_HEAD ; git show | head -1
```

`working tree` don't include `untracked files`

### commit

```
git commit -am "save arezzo files"
git commit --amend
    -c, --reedit-message <commit>   # reuse and edit message from specified commit
    -C, --reuse-message <commit>    # reuse message from specified commit
```

### log

```
git log [<options>] [<revision-range>] [[--] <path>...]
git show [<options>] <object>...
git show [path] # details of last commit log
git log --since=2.weeks
```

### branch and merge

```
git branch -a       # list all

git checkout -b dev # create and checkout a new branch

git checkout master
git merge dev       # merge dev into master
    --squash              create a single commit instead of doing a merge
    --abort               abort the current in-progress merge
```

### Undo

https://www.atlassian.com/git/tutorials/resetting-checking-out-and-reverting

```
git checkout -- <file>    # discard changes in working directory

git reset HEAD~2    # undo 2 changes that haven’t been shared
git reset <paths>   # opposite of `git add <paths>`
    --soft                reset HEAD only
    --mixed               reset HEAD and index (default)
    --hard                reset HEAD, index and working tree
    --merge               reset HEAD, index and working tree
    --keep                reset HEAD but keep local changes

git revert HEAD~2   # undo 2 changes on a public branch
```

https://stackoverflow.com/questions/3639342

```
git reset master
git checkout master
```

![](https://i.stack.imgur.com/UWGiw.png)

### stashing

```
git stash
git stash list
git stash apply/pop
git stash apply stash@{2}
git stash drop
git stash drop stash@{0}
```

### remote and push

https://git-scm.com/book/en/v2/Git-Internals-The-Refspec

```
git remote -v
git remote add [<options>] <name> <url>
    -f, --fetch           fetch the remote branches
    --tags
    --no-tags
    -t, --track <branch>        # branch(es) to track
    -m, --master <branch>
    --mirror[=<push|fetch>]     # set up remote as a mirro

cat .git/config
    `refspec`:     +<src>:<dst>
    <src> is the pattern for references on the remote side
    <dst> is where those references will be tracked locally

    [remote "origin"]
        fetch = +refs/heads/*:refs/remotes/origin/*
        fetch = +refs/heads/master:refs/remotes/origin/master
        fetch = +refs/heads/foo/*:refs/remotes/origin/foo/*

git push -u origin master:refs/heads/foo/master

        push = refs/heads/master:refs/heads/qa/master

tree .git/refs/
    .git/refs/
    ├── heads
    │   ├── dev
    │   └── master
    ├── remotes
    │   └── origin
    │       └── HEAD
    └── tags

git push [<options>] [<repository> [<refspec>...]]
    -u, --set-upstream    set upstream for git pull/status
git pull origin master # fetch + merge
```

#### delete remote branch

```
git push origin :topic
git push origin --delete topic
```

## config

```
git config -l
    --global              ~/.gitconfig
    --local               .git/config
        core.repositoryformatversion=0
        core.filemode=true
        core.bare=false
        core.logallrefupdates=true
    --system              /etc/gitconfig

    --get                 get value: name [value-regex]
    --get-all             get all values: key [value-regex]
    --get-regexp          get values for regexp: name-regex [value-regex]
    --get-urlmatch        get value specific for the URL: section[.var] URL
    --replace-all         replace all matching variables: name value [value_regex]
    --add                 add a new variable: name value
    --unset               remove a variable: name [value-regex]
    --unset-all           remove all matches: name [value-regex]

git config --global push.default simple
git config --list --show-origin
```

### Proxy

```
git config --global http.proxy http://$IP:$Port
```

## filter-branch

https://manishearth.github.io/blog/2017/03/05/understanding-git-filter-branch/

```
[--setup <command>] 
[--env-filter <command>]
[--tree-filter <command>] 
[--index-filter <command>]
[--parent-filter <command>] 
[--msg-filter <command>]
[--commit-filter <command>] 
[--tag-name-filter <command>]
[--subdirectory-filter <directory>] 
[--original <namespace>]
[-d <directory>] [-f | --force] [--] [<rev-list options>...]
```

## Remove File

### Unpushed commit

```
git rm --cached giant_file # leave it on disk
git commit --amend -CHEAD
```

### Every commit

```
git filter-branch --tree-filter 'rm -f filename' HEAD
    --all       # all branches

git filter-branch --index-filter \
    'git rm --cached --ignore-unmatch filename' HEAD
```

### from Github

https://help.github.com/articles/removing-sensitive-data-from-a-repository/

## rebase

https://git-scm.com/book/en/v2/Git-Branching-Rebasing

```
git remote add upstream https://github.com/yeasy/docker_practice
git fetch upstream
git checkout master
git rebase upstream/master
git push -f origin master
```

## fork

https://stackoverflow.com/questions/14587045/how-to-merge-branch-of-forked-repo-into-master-branch-of-original-repo

## Submodules

https://git-scm.com/book/en/v2/Git-Tools-Submodules\
treat the two projects as separate yet still be able to use one from within the other.

## Github API

https://developer.github.com/v3/repos/

### Download by tag

```
curl -sSL https://api.github.com/repos/django/django/tags \
    | jq '.[0].zipball_url' | xargs -t wget -O file.zip
```

### curl Github

https://github.com/settings/tokens

```
curl -H 'Authorization: token INSERT_ACCESS_TOKEN_HERE' \
    -H 'Accept: application/vnd.github.v3.raw' -O -L \
    https://api.github.com/repos/owner/repo/contents/path
```

### Query latest release

```
curl -sSL https://api.github.com/repos/ParsePlatform/Parse-SDK-Android/releases/latest \
    | jq '.zipball_url' | xargs -t wget -O file.zip
```

## Github

check watchers: https://github.com/{user}/{project}/watchers

## Self-host git servers

Go: https://github.com/go-gitea/gitea\
Go: https://github.com/gogs/gogs\
Ruby: https://gitlab.com/gitlab-org/gitlab

## Tools

curl -L https://github.com...?raw=true\
.html to page, etc: https://rawgit.com/\
.js CDN: https://cdnjs.com/ https://cdn.jsdelivr.net/gh/user/repo@version/file\
.ipynb fast open: http://nbviewer.jupyter.org/\
Code search: https://about.sourcegraph.com/\
download: https://minhaskamal.github.io/DownGit/#/home
