<?php
/**
* Quick and dirty deploy script for Git repositories.
*
* Basic idea: you have a Git server (like Gitea, but just a bare repo should
* also work) where you host a repo that you want to deploy somewhere. The
* somewhere (same or other server) has a Web Server with PHP capabilities
* running (my use case: I develop a TYPO3 site package, TYPO3 runs on PHP).
* In your Git repo (server-side) you define post-receive git hook which just
* sends a simple HTTP GET request your deploy-server (over HTTTPS, of course)
* like https://example.com/quick-deploy.php?s=YOUR_SECRET. Where your secret
* is known to you, your git post-receive hook and the quick-deploy script.
* If the given secret matches the predefinded than a pull request in the given
* repository is attempted. It git fails, a 500 error will be returned.
* Additionally the git output will be printed.
*
* For the configuration look at config.example.json. Copy it and ajust it for
* a working setup.
*
* PHP version 7
*
* @package QuickDeploy
* @author Marcel Kapfer <opensource@mmk2410.org>
* @copyright 2020 Marcel Kapfer
* @license https://opensource.org/licenses/MIT MIT License
* @version v0.0.1
*/
/**
* Position of the configuration JSON file.
*/
define("CONFIG_FILE", "config.json");
/**
* Parse and print Git output.
*
* The output of a git command with the --progress flag is a little bit
* hard to parse. The progress messages need to be splited first and
* then printed.
*
* @param string $output output of a git command execution
*
* @return void
*/
function print_git_output($output)
{
foreach ($output as &$line) {
$line = preg_split("/\r\n|\n|\r/", $line);
foreach ($line as &$subline) {
echo($subline . "<br>");
}
}
}
/**
* Print something bold (<b></b>) and end with newline.
*
* Handy wrapper of the echo function which prints the text wrapped with a
* "<b></b>" tag and end with a <br>.
*
* @param string $output string to print in bold
*
* @return void
*/
function print_bold($output)
{
echo("<b>" . $output . "</b><br>");
}
/**
* Handle shell exit status.
*
* Checks if the exist status is zero or not and prints $action combined with a
* status message (failed or successful) as bold text.
*
* @param int $return_var exit code of called command
* @param string $action name/description of tried action
*
* @return void
*/
function handle_status($return_var, $action)
{
if ($return_var != 0) {
handle_error($action . " failed");
} else {
print_bold($action . " successful");
}
}
/**
* Print error and set HTTP status code.
*
* Print a error message in bold and set a 500 HTTP Error status. Additionally
* it exits the process.
*
* @param string $error_msg Error message that should be printed.
*
* @return void
*/
function handle_error($error_msg)
{
print_bold($error_msg);
http_response_code(500);
exit();
}
/**
* Read and parse configuration.
*
* Read the JSON configuration defined in CONFIG_FILE and parse it.
*
* @return array|null configuration
*/
function parse_config()
{
if (is_readable(CONFIG_FILE)) {
$config_data = file_get_contents(CONFIG_FILE);
return json_decode($config_data, true);
} else {
handle_error("Config file not found or not readable");
}
}
/**
* Verify and complete config.
*
* The configuration values "secret", "local-path" and "remote-path" are
* checked for existence and "branch" is set to "master" if not defined.
*
* @param array $config configuration array
*
* @return void
*/
function verify_config(&$config)
{
# Check if secret is set (config and GET parameter).
if (!isset($_GET["secret"])) {
handle_error("No secret given.");
}
# Check if local path is set
if (!isset($config["local-path"])) {
handle_error("No local path given.");
}
# Check if remote path is set
if (!isset($config["remote-path"])) {
handle_error("No remote path given.");
}
# Define branch name
if (!isset($config["branch"])) {
$config["branch"] = master;
}
}
/**
* Authenticate using the given secrets.
*
* Compares the secret stored in the configuration and the one given as secret
* get parameter.
*
* @param string $secret secret defined in the configuration
*
* @return void
*/
function authenticate($secret)
{
# Check if secret is set (config and GET parameter).
if (!isset($_GET["secret"])) {
handle_error("No secret as GET parameter given.");
}
# Compare given secrets
if (strcmp($secret, htmlspecialchars($_GET["secret"])) == 0) {
print_bold("Authentication sucessfull!");
} else {
handle_error("Authentication failed!");
}
}
/**
* Run git fetch and git checkout in the local repository.
*
* The changes for the specified branch will be fetched and the branch checked
* out.
*
* @param string $local_path path of the local repository
* @param string $branch branch name that should be checked out
*
* @return void
*/
function git_pull($local_path, $branch)
{
if (is_writable($local_path . "/.git")) {
# Switch to local repository
chdir($local_path);
# Fetch changes for pre-configured branch
print_bold("Fetching " . $branch . " branch.");
exec("git fetch --progress origin " . $branch . " 2>&1", $output, $return_var);
print_git_output($output);
handle_status($return_var, "Fetching");
# Switch to pre-configured branch
print_bold("Switching to " . $branch . " branch");
exec("git checkout --progress " . $branch . " 2>&1", $output, $return_var);
print_git_output($output);
handle_status($return_var, "Checkout");
} else {
handle_error("No .git directory found, but directory already exists.");
}
}
/**
* Run git clone in the local path.
*
* If the git repository is not yet created the given branch will be cloned.
*
* @param string $local_path Path of local repository
* @param string $remote_path Path/URL of remote repository
* @param string $branch Name of working branch
*
* @return void
*/
function git_clone($local_path, $remote_path, $branch)
{
# Clone remote repository into local path
print_bold("Repository doesn't exists. Trying to clone.");
exec("git clone --progress --branch=" . $branch . " " . $remote_path . " " . $local_path . " 2>&1", $output, $return_var);
print_git_output($output);
handle_status($return_var, "Cloning");
}
/**
* Main entry function.
*
* @return void
*/
function main()
{
# Preparations
$config = parse_config();
verify_config($config);
authenticate($config["secret"]);
# Actual deploy operations
if (is_writable($config["local-path"])) {
git_pull($config["local-path"], $config["branch"]);
} elseif (is_writable(dirname($config["local-path"]))) {
git_clone($config["local-path"], $config["remote-path"], $config["branch"]);
} else {
handle_error("Path doesn't exists, can't created or is not writable");
}
}
main();