Add a storage renamespace for mangling SQL dumpfiles into a new namespace

Summary:
Ref T7149. When users give us dumpfiles for import, they will almost inevitably use the `phabricator` namespace. They need to be renamed to use an instance namespace.

We can do this either by:

  - importing the data first, then renaming; or
  - renaming first, then importing.

This implements the second one, basically `storage renamespace --in dump.sql --from phabricator --to instancename > instance.sql`.

Renaming first is a little hackier since we have to `preg_match()` a SQL dump file, but I think it's better overall:

  - With only one database, it lets you dump/import without downtime.
  - If you have development stuff in a development environment in the `phabricator` namespace, you don't have to move it aside to do an import.
  - No possibility that two people doing an import at the same time on the same box will collide with each other.
  - You can do the rename once and then repeat the import process with the renamed dump more easily.
  - No tricky stuff with modern Phabricator running against an old dump and the database names not matching up.

None of this is super important, but it just makes large dumps a bit easier to work with, and the dumpfile format is regular enough that this seems unlikely to ever really not work.

Test Plan: Renamespaced a dump, did a `diff -u`, saw all the relevant parts changed (and only those parts changed).

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7149

Differential Revision: https://secure.phabricator.com/D12105

src/__phutil_library_map__.php

@@ -2511,6 +2511,7 @@ phutil_register_library_map(array(
     'PhabricatorStorageManagementDumpWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementDumpWorkflow.php',
     'PhabricatorStorageManagementProbeWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementProbeWorkflow.php',
     'PhabricatorStorageManagementQuickstartWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementQuickstartWorkflow.php',
+    'PhabricatorStorageManagementRenamespaceWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementRenamespaceWorkflow.php',
     'PhabricatorStorageManagementShellWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementShellWorkflow.php',
     'PhabricatorStorageManagementStatusWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementStatusWorkflow.php',
     'PhabricatorStorageManagementUpgradeWorkflow' => 'infrastructure/storage/management/workflow/PhabricatorStorageManagementUpgradeWorkflow.php',
@@ -5870,6 +5871,7 @@ phutil_register_library_map(array(
     'PhabricatorStorageManagementDumpWorkflow' => 'PhabricatorStorageManagementWorkflow',
     'PhabricatorStorageManagementProbeWorkflow' => 'PhabricatorStorageManagementWorkflow',
     'PhabricatorStorageManagementQuickstartWorkflow' => 'PhabricatorStorageManagementWorkflow',
+    'PhabricatorStorageManagementRenamespaceWorkflow' => 'PhabricatorStorageManagementWorkflow',
     'PhabricatorStorageManagementShellWorkflow' => 'PhabricatorStorageManagementWorkflow',
     'PhabricatorStorageManagementStatusWorkflow' => 'PhabricatorStorageManagementWorkflow',
     'PhabricatorStorageManagementUpgradeWorkflow' => 'PhabricatorStorageManagementWorkflow',

src/infrastructure/storage/management/workflow/PhabricatorStorageManagementRenamespaceWorkflow.php

@@ -0,0 +1,94 @@
+<?php
+
+final class PhabricatorStorageManagementRenamespaceWorkflow
+  extends PhabricatorStorageManagementWorkflow {
+
+  protected function didConstruct() {
+    $this
+      ->setName('renamespace')
+      ->setExamples(
+        '**renamespace** [__options__] '.
+        '--in __dump.sql__ --from __old__ --to __new__ > __out.sql__')
+      ->setSynopsis(pht('Change the database namespace of a .sql dump file.'))
+      ->setArguments(
+        array(
+          array(
+            'name' => 'in',
+            'param' => 'file',
+            'help' => pht('SQL dumpfile to process.'),
+          ),
+          array(
+            'name' => 'from',
+            'param' => 'namespace',
+            'help' => pht('Current database namespace used by dumpfile.'),
+          ),
+          array(
+            'name' => 'to',
+            'param' => 'namespace',
+            'help' => pht('Desired database namespace for output.'),
+          ),
+        ));
+  }
+
+  public function execute(PhutilArgumentParser $args) {
+    $console = PhutilConsole::getConsole();
+
+    $in = $args->getArg('in');
+    if (!strlen($in)) {
+      throw new PhutilArgumentUsageException(
+        pht('Specify the dumpfile to read with --in.'));
+    }
+
+    $from = $args->getArg('from');
+    if (!strlen($from)) {
+      throw new PhutilArgumentUsageException(
+        pht('Specify namespace to rename from with --from.'));
+    }
+
+    $to = $args->getArg('to');
+    if (!strlen($to)) {
+      throw new PhutilArgumentUsageException(
+        pht('Specify namespace to rename to with --to.'));
+    }
+
+    $patterns = array(
+      'use' => '@^(USE `)([^_]+)(_.*)$@',
+      'create' => '@^(CREATE DATABASE /\*.*?\*/ `)([^_]+)(_.*)$@',
+    );
+
+    $found = array_fill_keys(array_keys($patterns), 0);
+
+    $matches = null;
+    foreach (new LinesOfALargeFile($in) as $line) {
+
+      foreach ($patterns as $key => $pattern) {
+        if (preg_match($pattern, $line, $matches)) {
+          $namespace = $matches[2];
+          if ($namespace != $from) {
+            throw new Exception(
+              pht(
+                'Expected namespace "%s", found "%s": %s.',
+                $from,
+                $namespace,
+                $line));
+          }
+
+          $line = $matches[1].$to.$matches[3];
+          $found[$key]++;
+        }
+      }
+
+      echo $line."\n";
+    }
+
+    // Give the user a chance to catch things if the results are crazy.
+    $console->writeErr(
+      pht(
+        'Adjusted **%s** create statements and **%s** use statements.',
+        new PhutilNumber($found['create']),
+        new PhutilNumber($found['use']))."\n");
+
+    return 0;
+  }
+
+}