Relative symlinks for Deployer -- https://github.com/deployphp/deployer/issues/503

deployer-relative-symlinks.php

<?php

/**
 * Create symlinks for shared directories and files.
 *
 * This is a copy of the default `deploy:shared` task, but modified to create relative symlinks. See
 * `deploy:symlink` for details.
 */
task( 'deploy:shared', function() {
	$sharedPath = "{{deploy_path}}/shared";

	foreach ( get( 'shared_dirs' ) as $dir ) {
		// Remove from source.
		run( "if [ -d $(echo {{release_path}}/$dir) ]; then rm -rf {{release_path}}/$dir; fi" );

		// Create shared dir if it does not exist.
		run( "mkdir -p $sharedPath/$dir" );

		// Create path to shared dir in release dir if it does not exist.
		// (symlink will not create the path and will fail otherwise)
		run( "mkdir -p `dirname {{release_path}}/$dir`" );

		// Symlink shared dir to release dir
		$change_directory = 'cd {{release_path}}/' . dirname( $dir );
		$parent_levels    = str_repeat( '../', substr_count( $dir, '/' ) + 2 );
		$create_symlink   = "ln -nfs {$parent_levels}shared/$dir " . basename( $dir );

		run( "$change_directory && $create_symlink" );
	}

	foreach ( get( 'shared_files' ) as $file ) {
		$dirname = dirname( $file );
		// Remove from source.
		run( "if [ -f $(echo {{release_path}}/$file) ]; then rm -rf {{release_path}}/$file; fi" );
		// Ensure dir is available in release
		run( "if [ ! -d $(echo {{release_path}}/$dirname) ]; then mkdir -p {{release_path}}/$dirname;fi" );

		// Create dir of shared file
		run( "mkdir -p $sharedPath/" . $dirname );

		// Touch shared
		run( "touch $sharedPath/$file" );

		// Symlink shared dir to release dir
		$change_directory = 'cd {{release_path}}/' . dirname( $file );
		$parent_levels    = str_repeat( '../', substr_count( $file, '/' ) + 2 );
		$create_symlink   = "ln -sfn {$parent_levels}shared/$file " . basename( $file );

		run( "$change_directory && $create_symlink" );
	}
} )->desc( 'Creating symlinks for shared files' );

/**
 * Create symlink to last release.
 *
 * This is a copy of the default `deploy:symlink` task, but modified to create relative symlinks.
 *
 * See https://github.com/deployphp/deployer/issues/503
 *
 * On many shared hosting platforms, the user is chroot'd into a child directory, so absolute symlinks
 * fail because they require permission to execute on each folder in the path, all the way up to /
 *  - https://unix.stackexchange.com/a/21339/18886
 *  - https://gist.github.com/mkrisher/74721/revisions#diff-01cf30e04b9c4489ed9e927b99e3b66dR45
 *
 * Also, the symlinks need to be set relative to the symlink's target directory.
 *  - https://unix.stackexchange.com/a/15285/18886
 *  - https://askubuntu.com/a/524635
 */
task( 'deploy:symlink', function() {
	$relative_release_path = '.' . substr(
		env( 'release_path' ),
		strlen( env( 'deploy_path' ) )
	);
	env( 'relative_release_path', $relative_release_path );

	run( "cd {{deploy_path}} && ln -sfn {{relative_release_path}} current" ); // Atomic override symlink.
	run( "cd {{deploy_path}} && rm release" ); // Remove release link.
} )->desc( 'Creating symlink to release' );

/**
 * Rollback to previous release.
 *
 * This is a copy of the default `rollback` task, but modified to create relative symlinks. See
 * `deploy:symlink` for details.
 */
task( 'rollback', function() {
	$releases = env( 'releases_list' );

	if ( isset( $releases[1] ) ) {
		$releaseDir = "./releases/{$releases[1]}";

		// Symlink to old release.
		run( "cd {{deploy_path}} && ln -nfs $releaseDir current" );

		// Remove release
		run( "rm -rf ./releases/{$releases[0]}" );

		writeln( "Rollback to `{$releases[1]}` release was successful." );
	} else {
		writeln( "<comment>No more releases you can revert to.</comment>" );
	}
} )->desc( 'Rollback to previous release' );