Difficulty level

Intermediate

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Skills Required

• Knowledge of working on remote repositories (github / bitbucket etc) and on cloud server (Rackspace cloud / Amazon EC2 etc).
• Apache
• PHP

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Prior Requirements

• you have a local git repo
• with an online remote repository (github / bitbucket etc)
• and a cloud server (Rackspace cloud / Amazon EC2 etc)
  • your (PHP) scripts are served from /var/www/html/
  • your webpages are executed by apache
  • apache's home directory is /var/www/

(This describes a pretty standard apache setup on Redhat / Ubuntu / CentOS / Amazon AMI etc) you should be able to do the same with Java, Perl, RoR, JSP etc. however you'll need to recreate the (rather simple) PHP script.

git, rsync, and tar binaries are required on the server that's running the script (server machine).

Also, the system user that's running PHP needs to have the right ssh keys to access the remote repository (If it's a private repo) and have the required permissions to update the files on the server machine.

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1 - On your local machine

Here we add the deployment script and push it to the origin, the deployment script runs git commands to PULL from the origin thus updating your server

Grab a deployment script for your site

deploy.php

Add, commit and push this to github

git add deploy.php
git commit -m 'Added the git deployment script'
git push -u origin master

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2 - On your server

Here we install and setup git on the server, we also create an SSH key so the server can talk to the origin without using passwords etc

Install git...

After you've installed git, make sure it's a relatively new version - old scripts quickly become problematic as github / bitbucket / whatever will have the latests and greatest, if you don't have a recent version you'll need to figure out how to upgrade it :-)

git --version

...on CentOS 5.6

# Add a nice repo
rpm -Uvh http://repo.webtatic.com/yum/centos/5/latest.rpm
# Install git
yum install --enablerepo=webtatic git-all

...using generic yum

sudo yum install git-core

Setup git

git config --global user.name "Server"
git config --global user.email "[email protected]"

Create an ssh directory for the apache user

sudo mkdir /var/www/.ssh
sudo chown -R apache:apache /var/www/.ssh/

Generate a deploy key for apache user

sudo -Hu apache ssh-keygen -t rsa # choose "no passphrase"
sudo cat /var/www/.ssh/id_rsa.pub

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3 - On your origin (github / bitbucket)

Here we add the SSH key to the origin to allow your server to talk without passwords. In the case of GitHub we also setup a post-receive hook which will automatically call the deploy URL thus triggering a PULL request from the server to the origin

GitHub

1. Go to https://github.com/USERNAME/REPOSITORY/settings/keys and add your server SSH key (only needed for private repositories)
2. Go to https://github.com/USERNAME/REPOSITORY/admin/hooks
3. Select the WebHook URLs service hook
4. Enter the URL to your deployment script e.g. http://example.com/deploy.php?sat=YourSecretAccessTokenFromDeployFile
5. Click Update Settings

Bitbucket

1. Go to https://bitbucket.org/USERNAME/REPOSITORY/admin/deploy-keys and add your server SSH key (only needed for private repositories)
2. Go to https://bitbucket.org/USERNAME/REPOSITORY/admin/services
3. Add POST service
4. Enter the URL to your deployment script e.g. http://example.com/deploy.php?sat=YourSecretAccessTokenFromDeployFile
5. Click Save

Generic GIT

1. Configure the SSH keys
2. Add a executable .git/hooks/post_receive script that calls the script e.g.

#!/bin/sh
echo "Triggering the code deployment ..."
wget -q -O /dev/null http://example.com/deploy.php?sat=YourSecretAccessTokenFromDeployFile

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4 - On the Server

Here we clone the origin repo into a chmodded /var/www/html folder

Pull from origin

sudo chown -R apache:apache /var/www/html
sudo -Hu apache git clone [email protected]:you/server.git /var/www/html

Rejoice!

Now you're ready to go :-)

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Some notes

• Navigate the the deployment script to trigger a pull and see the output:
  • http://server.com/deploy.php
  • this is useful for debugging too ;-)
• When you push to GitHub your site will automatically ping the above url (and pull your code)
• When you push to Bitbucket you will need to manually ping the above url
• It would be trivial to setup another repo on your server for different branches (develop, release-candidate etc) - repeat most of the steps but checkout a branch after pulling the repo down

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GUIDES

Here are more guides from me

• Twitter Bootstrap
• GITHub Patch Mode: git add -p: The most powerful git feature you're not using yet

Sources

• Build auto-deploy with php and git(hub) on an EC2 Amazon AMI instance - who in turn referenced:
  • ec2-webapp / INSTALL.md
  • How to deploy your code from GitHub automatically