Schema upgrade script.

Summary:
Created a script the runs all the necessary patches for db schema.
Stores information in the db about the latest patch that was applied.

Test Plan:
Created two test files '024.test.sql' and '023.test.sql' in this order.
'023' creates a database and '024' creates a table in this db. First ran
'./upgrade_schema.php 23' and made sure that patches were applied in order.
Then ran './upgrade_schema.php' to make sure db was up-to-date. Checked
manually from the db that the database and table exists.

Reviewed By: epriestley
Reviewers: epriestley
CC: jungejason, epriestley, tuomaspelkonen
Differential Revision: 115

scripts/sql/upgrade_schema.php

@@ -0,0 +1,142 @@
+#!/usr/bin/env php
+<?php
+
+/*
+ * Copyright 2011 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+$root = dirname(dirname(dirname(__FILE__)));
+require_once $root.'/scripts/__init_script__.php';
+require_once $root.'/scripts/__init_env__.php';
+
+const TABLE_NAME = 'schema_version';
+
+if (isset($argv[1]) && !is_numeric($argv[1])) {
+  print
+    "USAGE: ./update_schema.php [first_patch_version]\n\n".
+    "run './update_schema.php 12' to apply all patches starting from ".
+    "version 12.\n".
+    "run './update_schema.php' to apply all patches that are new since\n".
+    "the last time this script was run\n\n";
+  exit(0);
+}
+
+// Use always the version from the commandline if it is defined
+$next_version = isset($argv[1]) ? (int)$argv[1] : null;
+
+// Dummy class needed for creating our database
+class DummyUser extends PhabricatorLiskDAO {
+  public function getApplicationName() {
+    return 'user';
+  }
+}
+
+// Class needed for setting up the actual SQL connection
+class PhabricatorSchemaVersion extends PhabricatorLiskDAO {
+  public function getApplicationName() {
+    return 'meta_data';
+  }
+}
+
+// Connect to 'phabricator_user' db first to create our db
+$conn = id(new DummyUser())->establishConnection('w');
+$create_sql = <<<END
+CREATE DATABASE IF NOT EXISTS `phabricator_meta_data`;
+END;
+queryfx($conn, $create_sql);
+
+// 'phabricator_meta_data' database exists, let's connect to it now
+$conn = id(new PhabricatorSchemaVersion())->establishConnection('w');
+$create_sql = <<<END
+CREATE TABLE IF NOT EXISTS phabricator_meta_data.`schema_version` (
+  `version` INTEGER not null
+);
+END;
+queryfx($conn, $create_sql);
+
+// Get the version only if commandline argument wasn't given
+if ($next_version === null) {
+  $version = queryfx_one(
+    $conn,
+    'SELECT * FROM %T',
+    TABLE_NAME);
+
+  if (!$version) {
+    print "*** No version information in the database ***\n";
+    print "*** Give the first patch version which to  ***\n";
+    print "*** apply as the command line argument     ***\n";
+    exit(-1);
+  }
+
+  $next_version = $version['version'] + 1;
+}
+
+// Find the patch files
+$patches_dir = $root.'/resources/sql/patches/';
+$finder = id(new FileFinder($patches_dir))
+  ->withSuffix('sql');
+$results = $finder->find();
+
+$patches = array();
+foreach ($results as $r) {
+  $matches = array();
+  if (preg_match('/(\d+)\..*\.sql$/', $r, $matches)) {
+    $patches[] = array('version' => (int)$matches[1],
+                       'file' => $r);
+  } else {
+    print
+      "*** WARNING : File {$r} does not follow the normal naming ".
+      "convention. ***\n";
+  }
+}
+
+// Files are in some 'random' order returned by the operating system
+// We need to apply them in proper order
+$patches = isort($patches, 'version');
+
+$patch_applied = false;
+foreach ($patches as $patch) {
+  if ($patch['version'] < $next_version) {
+    continue;
+  }
+
+  print "Applying patch {$patch['file']}\n";
+
+  $path = Filesystem::resolvePath($patches_dir.$patch['file']);
+
+  $user = PhabricatorEnv::getEnvConfig('mysql.user');
+  $pass = PhabricatorEnv::getEnvConfig('mysql.pass');
+  $host = PhabricatorEnv::getEnvConfig('mysql.host');
+
+  list($stdout, $stderr) = execx(
+    "mysql --user=%s --password=%s --host=%s < %s",
+    $user, $pass, $host, $path);
+
+  if ($stderr) {
+    print $stderr;
+    exit(-1);
+  }
+
+  // Patch was successful, update the db with the latest applied patch version
+  // 'DELETE' and 'INSERT' instead of update, because the table might be empty
+  queryfx($conn, 'DELETE FROM %T', TABLE_NAME);
+  queryfx($conn, 'INSERT INTO %T values (%d)', TABLE_NAME, $patch['version']);
+
+  $patch_applied = true;
+}
+
+if (!$patch_applied) {
+  print "Your database is already up-to-date\n";
+}