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@ -1,7 +1,3 @@
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# JM inventory dynamic aws ec2
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# vault
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# roles
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---
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category: tool
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tool: ansible
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@ -247,10 +243,14 @@ You can use the jinja in the CLI too
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ansible -m shell -a 'echo {{ my_variable }}` -e 'my_variable=something, playbook_parameter=twentytwo" localhost
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```
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### Jinja2 and templates
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jinja filters
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### Jinja2 filters
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Junja is powerfull. It has built-in many usefull functions.
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```jinja
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# get first item of the list
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{{ some_list | first() }}
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# if variable is undefined - use default value
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{{ some_variable | default('default_value') }}
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```
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#### ansible-vault
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To maintain **ifrastructure as a code** you need to store secrets.
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@ -295,25 +295,67 @@ $ etc/inv/ec2.py --refresh
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$ ansible -m ping all -i etc/inv/ec2.py
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```
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#### ansible profiling - callback
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It is ok that your playbook executes some time. Sometimes you may like to speed things up :)
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### ansible profiling - callback
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Since ansible 2.x there is bouilt-in callback for task execution profiling
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### facts-cache and ansible-cmdb
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```
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vi ansible.cfg
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#set this to:
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callback_whitelist = profile_tasks
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```
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### debugging ansible
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#### facts-cache and ansible-cmdb
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You can pool some infrmations of you environment from another hosts.
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If the informations does not change - you may consider using a facts_cache to speed things up.
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### Infrastructure as a code - what about Ansible
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virtualenv
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```
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vi ansible.cfg
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### ansible - dynamic in AWS
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# if set to a persistent type (not 'memory', for example 'redis') fact values
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# from previous runs in Ansible will be stored. This may be useful when
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# wanting to use, for example, IP information from one group of servers
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# without having to talk to them in the same playbook run to get their
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# current IP information.
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fact_caching = jsonfile
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fact_caching_connection = ~/facts_cache
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fact_caching_timeout = 86400
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```
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### create instance in AWS
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I like to use `jsonfile` as my backend. It allows to use another project
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`ansible-cmdb` [github] that generates a HTML page of your inventory resources. A nice 'free' addition!
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### create env in AWS
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#### debugging ansible
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When your job fails - it is good to be effective with debugging.
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1. Increase verbosiy by using multiple -v **[ -vvvvv]**
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2. If variable is undefined
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3. If variable (dictionary or a list) is undefined
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4. Jinja template debug
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#### Infrastructure as a code - what about Ansible
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You already know, that ansible-vault allow you to store your poufne data along with your code (in repository). You can go further - and define your ansible installation and configuration as-a-code.
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See `environment.sh` to learn how to install the ansible itself inside a `virtualenv` that is not attached to your operating system (can be changed by non-privilages user), and as additiinal benefit - upgrading version of ansible is as easy as installing new version in new virtualenv. You can have multiple versions of Ansible present in the same time. This is very helpfull!
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```bash
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# recreate ansible 2.x venv
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$ rm -rf venv2
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$ source environment2.sh
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# execute playbook
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(venv2)$ ansible-playbook playbooks/ansible1.9_playbook.yml # would fail - deprecated syntax
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# now lets install ansible 1.9.x next to ansible 2.x
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(venv2)$ deactivate
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$ source environment.1.9.sh
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# execute playbook
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(venv1.9)$ ansible-playbook playbooks/ansible1.9_playbook.yml # works!
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# please note that you have both venv1.9 and venv2 present - you need to (de)activate one - that is all
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```
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### Naming
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## Bonus
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### Bonus
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### writing own module
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@ -321,14 +363,67 @@ virtualenv
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### Web-UI: Ansible Tower, Jenkins, Rundeck
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#become-user, become
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#### Ansible Tower
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Ansible provides a Web User Interface called `Ansible Tower`.
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It is a convienient way to run Ansible Playbooks, have proper user management, log retention, and cron (periodic jobs).
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Personaly I'm not a fan of it - it's to expensive for my cases, and the trial is 10 inventory-hosts only.
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For my usecases I hide the 'pure ansible' commands behind other projects.
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#### Rundeck
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This is nice, secure interface, that allows you to execute a jobs of your choice (CLI, script, execution plan).
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It can perform roling-deployment (without Ansible), can integrate with clouds, etc.
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#### Jenkins
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For my 'business cases' I use Jenkins - it has a 'cron', jobs can be binded into 'pipelines'.
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### become-user, become
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### ansible - dynamic in AWS
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### create instance in AWS
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### create env in AWS
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### Tips and tricks
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AND,XOR
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--check --diff
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tags
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meta
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no_logs
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##### --check -C
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Always make sure that your playbook can executes in 'dry run' mode (--check), and it's execution is not declaring 'Changed' objects.
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##### --diff -D
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Diff is usefull to see nice detail of the files changed
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It compare 'in memory' the files like `diff -BbruN fileA fileB`
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##### Execute hosts with 'regex'
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```bash
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ansible -m ping web*
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```
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#####
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Host groups can be joined, negated, etc
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```bash
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ansible -m ping web*:!backend:monitoring:&allow_change
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```
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##### Tagging
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You should tag some (not all) objects - a task in a playbook, all tasks included form a role, etc.
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It allwos you to execute the choosen parts of the playbook.
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##### no_logs: True
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You may see, that some roles print a lot of output in verbose mode. There is also a debug module.
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This is the place where credentials may leak. Use `no_log` to hide the output.
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##### Debug module
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allows to print a value to the screen
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##### Register the output of a task
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You can register the output (stdout), rc (return code), stderr of a task with the `register` command.
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##### Conditionals: when:
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##### Loop: with, with_items, with_dict, with_together
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## Introduction
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Ansible is (one of the many) orchestration tools. It allows you to controll your environment (infrastructure and a code) and automate the manual tasks.
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@ -373,577 +468,7 @@ But ansible is way more! It provides an execution plans, an API, library, callba
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---
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Github template placeholder - to be removed
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# JM inventory dynamic aws ec2
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# vault
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# roles
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### Centralized Versioning VS Distributed Versioning
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* Centralized version control focuses on synchronizing, tracking, and backing
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up files.
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* Distributed version control focuses on sharing changes. Every change has a
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unique id.
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* Distributed systems have no defined structure. You could easily have a SVN
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style, centralized system, with git.
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[Additional Information](http://git-scm.com/book/en/Getting-Started-About-Version-Control)
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### Why Use Git?
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* Can work offline.
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* Collaborating with others is easy!
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* Branching is easy!
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* Branching is fast!
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* Merging is easy!
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* Git is fast.
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* Git is flexible.
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## Git Architecture
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### Repository
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A set of files, directories, historical records, commits, and heads. Imagine it
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as a source code data structure, with the attribute that each source code
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"element" gives you access to its revision history, among other things.
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A git repository is comprised of the .git directory & working tree.
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### .git Directory (component of repository)
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The .git directory contains all the configurations, logs, branches, HEAD, and
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more.
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[Detailed List.](http://gitready.com/advanced/2009/03/23/whats-inside-your-git-directory.html)
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### Working Tree (component of repository)
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This is basically the directories and files in your repository. It is often
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referred to as your working directory.
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### Index (component of .git dir)
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The Index is the staging area in git. It's basically a layer that separates
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your working tree from the Git repository. This gives developers more power
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over what gets sent to the Git repository.
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### Commit
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A git commit is a snapshot of a set of changes, or manipulations to your
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Working Tree. For example, if you added 5 files, and removed 2 others, these
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changes will be contained in a commit (or snapshot). This commit can then be
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pushed to other repositories, or not!
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### Branch
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A branch is essentially a pointer to the last commit you made. As you go on
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committing, this pointer will automatically update to point the latest commit.
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### Tag
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A tag is a mark on specific point in history. Typically people use this
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functionality to mark release points (v1.0, and so on)
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### HEAD and head (component of .git dir)
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HEAD is a pointer that points to the current branch. A repository only has 1
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*active* HEAD.
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head is a pointer that points to any commit. A repository can have any number
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of heads.
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### Stages of Git
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* Modified - Changes have been made to a file but file has not been committed
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to Git Database yet
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* Staged - Marks a modified file to go into your next commit snapshot
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* Committed - Files have been committed to the Git Database
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### Conceptual Resources
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* [Git For Computer Scientists](http://eagain.net/articles/git-for-computer-scientists/)
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* [Git For Designers](http://hoth.entp.com/output/git_for_designers.html)
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## Commands
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### init
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Create an empty Git repository. The Git repository's settings, stored
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information, and more is stored in a directory (a folder) named ".git".
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```bash
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$ git init
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```
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### config
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To configure settings. Whether it be for the repository, the system itself,
|
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or global configurations ( global config file is `~/.gitconfig` ).
|
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|
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```bash
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# Print & Set Some Basic Config Variables (Global)
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$ git config --global user.email "MyEmail@Zoho.com"
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$ git config --global user.name "My Name"
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```
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[Learn More About git config.](http://git-scm.com/docs/git-config)
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### help
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To give you quick access to an extremely detailed guide of each command. Or to
|
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just give you a quick reminder of some semantics.
|
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|
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```bash
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# Quickly check available commands
|
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$ git help
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# Check all available commands
|
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$ git help -a
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# Command specific help - user manual
|
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# git help <command_here>
|
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$ git help add
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$ git help commit
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$ git help init
|
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# or git <command_here> --help
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$ git add --help
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$ git commit --help
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$ git init --help
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```
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|
||||
### ignore files
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||||
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To intentionally untrack file(s) & folder(s) from git. Typically meant for
|
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private & temp files which would otherwise be shared in the repository.
|
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```bash
|
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$ echo "temp/" >> .gitignore
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$ echo "private_key" >> .gitignore
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```
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### status
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To show differences between the index file (basically your working copy/repo)
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and the current HEAD commit.
|
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```bash
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# Will display the branch, untracked files, changes and other differences
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$ git status
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# To learn other "tid bits" about git status
|
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$ git help status
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```
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### add
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To add files to the staging area/index. If you do not `git add` new files to
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the staging area/index, they will not be included in commits!
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```bash
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# add a file in your current working directory
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$ git add HelloWorld.java
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# add a file in a nested dir
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$ git add /path/to/file/HelloWorld.c
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# Regular Expression support!
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$ git add ./*.java
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```
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This only adds a file to the staging area/index, it doesn't commit it to the
|
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working directory/repo.
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### branch
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Manage your branches. You can view, edit, create, delete branches using this
|
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command.
|
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|
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```bash
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# list existing branches & remotes
|
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$ git branch -a
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# create a new branch
|
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$ git branch myNewBranch
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# delete a branch
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$ git branch -d myBranch
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# rename a branch
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# git branch -m <oldname> <newname>
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$ git branch -m myBranchName myNewBranchName
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# edit a branch's description
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$ git branch myBranchName --edit-description
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```
|
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||||
### tag
|
||||
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||||
Manage your tags
|
||||
|
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```bash
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# List tags
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$ git tag
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||||
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||||
# Create a annotated tag
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# The -m specifies a tagging message,which is stored with the tag.
|
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# If you don’t specify a message for an annotated tag,
|
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# Git launches your editor so you can type it in.
|
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$ git tag -a v2.0 -m 'my version 2.0'
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# Show info about tag
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# That shows the tagger information, the date the commit was tagged,
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# and the annotation message before showing the commit information.
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$ git show v2.0
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# Push a single tag to remote
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$ git push origin v2.0
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||||
# Push a lot of tags to remote
|
||||
$ git push origin --tags
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```
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### checkout
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||||
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||||
Updates all files in the working tree to match the version in the index, or
|
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specified tree.
|
||||
|
||||
```bash
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||||
# Checkout a repo - defaults to master branch
|
||||
$ git checkout
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||||
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||||
# Checkout a specified branch
|
||||
$ git checkout branchName
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||||
|
||||
# Create a new branch & switch to it
|
||||
# equivalent to "git branch <name>; git checkout <name>"
|
||||
|
||||
$ git checkout -b newBranch
|
||||
```
|
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|
||||
### clone
|
||||
|
||||
Clones, or copies, an existing repository into a new directory. It also adds
|
||||
remote-tracking branches for each branch in the cloned repo, which allows you
|
||||
to push to a remote branch.
|
||||
|
||||
```bash
|
||||
# Clone learnxinyminutes-docs
|
||||
$ git clone https://github.com/adambard/learnxinyminutes-docs.git
|
||||
|
||||
# shallow clone - faster cloning that pulls only latest snapshot
|
||||
$ git clone --depth 1 https://github.com/adambard/learnxinyminutes-docs.git
|
||||
|
||||
# clone only a specific branch
|
||||
$ git clone -b master-cn https://github.com/adambard/learnxinyminutes-docs.git --single-branch
|
||||
```
|
||||
|
||||
### commit
|
||||
|
||||
Stores the current contents of the index in a new "commit." This commit
|
||||
contains the changes made and a message created by the user.
|
||||
|
||||
```bash
|
||||
# commit with a message
|
||||
$ git commit -m "Added multiplyNumbers() function to HelloWorld.c"
|
||||
|
||||
# automatically stage modified or deleted files, except new files, and then commit
|
||||
$ git commit -a -m "Modified foo.php and removed bar.php"
|
||||
|
||||
# change last commit (this deletes previous commit with a fresh commit)
|
||||
$ git commit --amend -m "Correct message"
|
||||
```
|
||||
|
||||
### diff
|
||||
|
||||
Shows differences between a file in the working directory, index and commits.
|
||||
|
||||
```bash
|
||||
# Show difference between your working dir and the index
|
||||
$ git diff
|
||||
|
||||
# Show differences between the index and the most recent commit.
|
||||
$ git diff --cached
|
||||
|
||||
# Show differences between your working dir and the most recent commit
|
||||
$ git diff HEAD
|
||||
```
|
||||
|
||||
### grep
|
||||
|
||||
Allows you to quickly search a repository.
|
||||
|
||||
Optional Configurations:
|
||||
|
||||
```bash
|
||||
# Thanks to Travis Jeffery for these
|
||||
# Set line numbers to be shown in grep search results
|
||||
$ git config --global grep.lineNumber true
|
||||
|
||||
# Make search results more readable, including grouping
|
||||
$ git config --global alias.g "grep --break --heading --line-number"
|
||||
```
|
||||
|
||||
```bash
|
||||
# Search for "variableName" in all java files
|
||||
$ git grep 'variableName' -- '*.java'
|
||||
|
||||
# Search for a line that contains "arrayListName" and, "add" or "remove"
|
||||
$ git grep -e 'arrayListName' --and \( -e add -e remove \)
|
||||
```
|
||||
|
||||
Google is your friend; for more examples
|
||||
[Git Grep Ninja](http://travisjeffery.com/b/2012/02/search-a-git-repo-like-a-ninja)
|
||||
|
||||
### log
|
||||
|
||||
Display commits to the repository.
|
||||
|
||||
```bash
|
||||
# Show all commits
|
||||
$ git log
|
||||
|
||||
# Show only commit message & ref
|
||||
$ git log --oneline
|
||||
|
||||
# Show merge commits only
|
||||
$ git log --merges
|
||||
|
||||
# Show all commits represented by an ASCII graph
|
||||
$ git log --graph
|
||||
```
|
||||
|
||||
### merge
|
||||
|
||||
"Merge" in changes from external commits into the current branch.
|
||||
|
||||
```bash
|
||||
# Merge the specified branch into the current.
|
||||
$ git merge branchName
|
||||
|
||||
# Always generate a merge commit when merging
|
||||
$ git merge --no-ff branchName
|
||||
```
|
||||
|
||||
### mv
|
||||
|
||||
Rename or move a file
|
||||
|
||||
```bash
|
||||
# Renaming a file
|
||||
$ git mv HelloWorld.c HelloNewWorld.c
|
||||
|
||||
# Moving a file
|
||||
$ git mv HelloWorld.c ./new/path/HelloWorld.c
|
||||
|
||||
# Force rename or move
|
||||
# "existingFile" already exists in the directory, will be overwritten
|
||||
$ git mv -f myFile existingFile
|
||||
```
|
||||
|
||||
### pull
|
||||
|
||||
Pulls from a repository and merges it with another branch.
|
||||
|
||||
```bash
|
||||
# Update your local repo, by merging in new changes
|
||||
# from the remote "origin" and "master" branch.
|
||||
# git pull <remote> <branch>
|
||||
$ git pull origin master
|
||||
|
||||
# By default, git pull will update your current branch
|
||||
# by merging in new changes from its remote-tracking branch
|
||||
$ git pull
|
||||
|
||||
# Merge in changes from remote branch and rebase
|
||||
# branch commits onto your local repo, like: "git fetch <remote> <branch>, git
|
||||
# rebase <remote>/<branch>"
|
||||
$ git pull origin master --rebase
|
||||
```
|
||||
|
||||
### push
|
||||
|
||||
Push and merge changes from a branch to a remote & branch.
|
||||
|
||||
```bash
|
||||
# Push and merge changes from a local repo to a
|
||||
# remote named "origin" and "master" branch.
|
||||
# git push <remote> <branch>
|
||||
$ git push origin master
|
||||
|
||||
# By default, git push will push and merge changes from
|
||||
# the current branch to its remote-tracking branch
|
||||
$ git push
|
||||
|
||||
# To link up current local branch with a remote branch, add -u flag:
|
||||
$ git push -u origin master
|
||||
# Now, anytime you want to push from that same local branch, use shortcut:
|
||||
$ git push
|
||||
```
|
||||
|
||||
### stash
|
||||
|
||||
Stashing takes the dirty state of your working directory and saves it on a
|
||||
stack of unfinished changes that you can reapply at any time.
|
||||
|
||||
Let's say you've been doing some work in your git repo, but you want to pull
|
||||
from the remote. Since you have dirty (uncommited) changes to some files, you
|
||||
are not able to run `git pull`. Instead, you can run `git stash` to save your
|
||||
changes onto a stack!
|
||||
|
||||
```bash
|
||||
$ git stash
|
||||
Saved working directory and index state \
|
||||
"WIP on master: 049d078 added the index file"
|
||||
HEAD is now at 049d078 added the index file
|
||||
(To restore them type "git stash apply")
|
||||
```
|
||||
|
||||
Now you can pull!
|
||||
|
||||
```bash
|
||||
git pull
|
||||
```
|
||||
`...changes apply...`
|
||||
|
||||
Now check that everything is OK
|
||||
|
||||
```bash
|
||||
$ git status
|
||||
# On branch master
|
||||
nothing to commit, working directory clean
|
||||
```
|
||||
|
||||
You can see what "hunks" you've stashed so far using `git stash list`.
|
||||
Since the "hunks" are stored in a Last-In-First-Out stack, our most recent
|
||||
change will be at top.
|
||||
|
||||
```bash
|
||||
$ git stash list
|
||||
stash@{0}: WIP on master: 049d078 added the index file
|
||||
stash@{1}: WIP on master: c264051 Revert "added file_size"
|
||||
stash@{2}: WIP on master: 21d80a5 added number to log
|
||||
```
|
||||
|
||||
Now let's apply our dirty changes back by popping them off the stack.
|
||||
|
||||
```bash
|
||||
$ git stash pop
|
||||
# On branch master
|
||||
# Changes not staged for commit:
|
||||
# (use "git add <file>..." to update what will be committed)
|
||||
#
|
||||
# modified: index.html
|
||||
# modified: lib/simplegit.rb
|
||||
#
|
||||
```
|
||||
|
||||
`git stash apply` does the same thing
|
||||
|
||||
Now you're ready to get back to work on your stuff!
|
||||
|
||||
[Additional Reading.](http://git-scm.com/book/en/v1/Git-Tools-Stashing)
|
||||
|
||||
### rebase (caution)
|
||||
|
||||
Take all changes that were committed on one branch, and replay them onto
|
||||
another branch.
|
||||
*Do not rebase commits that you have pushed to a public repo*.
|
||||
|
||||
```bash
|
||||
# Rebase experimentBranch onto master
|
||||
# git rebase <basebranch> <topicbranch>
|
||||
$ git rebase master experimentBranch
|
||||
```
|
||||
|
||||
[Additional Reading.](http://git-scm.com/book/en/Git-Branching-Rebasing)
|
||||
|
||||
### reset (caution)
|
||||
|
||||
Reset the current HEAD to the specified state. This allows you to undo merges,
|
||||
pulls, commits, adds, and more. It's a great command but also dangerous if you
|
||||
don't know what you are doing.
|
||||
|
||||
```bash
|
||||
# Reset the staging area, to match the latest commit (leaves dir unchanged)
|
||||
$ git reset
|
||||
|
||||
# Reset the staging area, to match the latest commit, and overwrite working dir
|
||||
$ git reset --hard
|
||||
|
||||
# Moves the current branch tip to the specified commit (leaves dir unchanged)
|
||||
# all changes still exist in the directory.
|
||||
$ git reset 31f2bb1
|
||||
|
||||
# Moves the current branch tip backward to the specified commit
|
||||
# and makes the working dir match (deletes uncommited changes and all commits
|
||||
# after the specified commit).
|
||||
$ git reset --hard 31f2bb1
|
||||
```
|
||||
|
||||
### reflog (caution)
|
||||
|
||||
Reflog will list most of the git commands you have done for a given time period,
|
||||
default 90 days.
|
||||
|
||||
This give you the a change to reverse any git commands that have gone wrong
|
||||
for instance if a rebase is has broken your application.
|
||||
|
||||
You can do this:
|
||||
|
||||
1. `git reflog` to list all of the git commands for the rebase
|
||||
```
|
||||
38b323f HEAD@{0}: rebase -i (finish): returning to refs/heads/feature/add_git_reflog
|
||||
38b323f HEAD@{1}: rebase -i (pick): Clarify inc/dec operators
|
||||
4fff859 HEAD@{2}: rebase -i (pick): Update java.html.markdown
|
||||
34ed963 HEAD@{3}: rebase -i (pick): [yaml/en] Add more resources (#1666)
|
||||
ed8ddf2 HEAD@{4}: rebase -i (pick): pythonstatcomp spanish translation (#1748)
|
||||
2e6c386 HEAD@{5}: rebase -i (start): checkout 02fb96d
|
||||
```
|
||||
2. Select where to reset to, in our case its `2e6c386`, or `HEAD@{5}`
|
||||
3. 'git reset --hard HEAD@{5}' this will reset your repo to that head
|
||||
4. You can start the rebase again or leave it alone.
|
||||
|
||||
[Additional Reading.](https://git-scm.com/docs/git-reflog)
|
||||
|
||||
### revert
|
||||
|
||||
Revert can be used to undo a commit. It should not be confused with reset which
|
||||
restores the state of a project to a previous point. Revert will add a new
|
||||
commit which is the inverse of the specified commit, thus reverting it.
|
||||
|
||||
```bash
|
||||
# Revert a specified commit
|
||||
$ git revert <commit>
|
||||
```
|
||||
|
||||
### rm
|
||||
|
||||
The opposite of git add, git rm removes files from the current working tree.
|
||||
|
||||
```bash
|
||||
# remove HelloWorld.c
|
||||
$ git rm HelloWorld.c
|
||||
|
||||
# Remove a file from a nested dir
|
||||
$ git rm /pather/to/the/file/HelloWorld.c
|
||||
```
|
||||
|
||||
## Further Information
|
||||
|
||||
* [tryGit - A fun interactive way to learn Git.](http://try.github.io/levels/1/challenges/1)
|
||||
|
||||
* [Learn Git Branching - the most visual and interactive way to learn Git on the web](http://learngitbranching.js.org/)
|
||||
|
||||
* [Udemy Git Tutorial: A Comprehensive Guide](https://blog.udemy.com/git-tutorial-a-comprehensive-guide/)
|
||||
|
||||
* [Git Immersion - A Guided tour that walks through the fundamentals of git](http://gitimmersion.com/)
|
||||
|
||||
* [git-scm - Video Tutorials](http://git-scm.com/videos)
|
||||
|
||||
* [git-scm - Documentation](http://git-scm.com/docs)
|
||||
|
||||
* [Atlassian Git - Tutorials & Workflows](https://www.atlassian.com/git/)
|
||||
|
||||
* [SalesForce Cheat Sheet](http://res.cloudinary.com/hy4kyit2a/image/upload/SF_git_cheatsheet.pdf)
|
||||
|
||||
* [GitGuys](http://www.gitguys.com/)
|
||||
|
||||
* [Git - the simple guide](http://rogerdudler.github.io/git-guide/index.html)
|
||||
|
||||
* [Pro Git](http://www.git-scm.com/book/en/v2)
|
||||
|
||||
* [An introduction to Git and GitHub for Beginners (Tutorial)](http://product.hubspot.com/blog/git-and-github-tutorial-for-beginners)
|
||||
|
Loading…
Reference in New Issue
Block a user