Add migration to encourage rebuilding repository identities

Summary: Ref T12164. Defines a new manual activity that suggests rebuilding repository identities before Phabricator begins to rely on them.

Test Plan:
- Ran migration, observed expected setup issue: {F5788217}
- Ran `bin/config done identities` and observed setup issue get marked as done.
- Ran `/bin/storage upgrade --apply phabricator:20170912.ferret.01.activity.php` to make sure I didn't break the reindex migration; observed reindex setup issue appear as expected.
- Ran `./bin/config done reindex` and observed reindex issue cleared as expected.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin, PHID-OPKG-gm6ozazyms6q6i22gyam

Maniphest Tasks: T12164

Differential Revision: https://secure.phabricator.com/D19497

resources/sql/autopatches/20180809.repo_identities.activity.php

@@ -0,0 +1,20 @@
+<?php
+
+// Advise installs to rebuild the repository identities.
+
+// If the install has no commits (or no commits that lack an
+// authorIdentityPHID), don't require a rebuild.
+$commits = id(new PhabricatorRepositoryCommit())
+  ->loadAllWhere('authorIdentityPHID IS NULL LIMIT 1');
+
+if (!$commits) {
+  return;
+}
+
+try {
+  id(new PhabricatorConfigManualActivity())
+    ->setActivityType(PhabricatorConfigManualActivity::TYPE_IDENTITIES)
+    ->save();
+} catch (AphrontDuplicateKeyQueryException $ex) {
+  // If we've already noted that this activity is required, just move on.
+}

src/applications/config/check/PhabricatorManualActivitySetupCheck.php

@@ -13,10 +13,21 @@ final class PhabricatorManualActivitySetupCheck
     foreach ($activities as $activity) {
       $type = $activity->getActivityType();
 
-      // For now, there is only one type of manual activity. It's not clear
-      // if we're really going to have too much more of this stuff so this
-      // is a bit under-designed for now.
+      switch ($type) {
+        case PhabricatorConfigManualActivity::TYPE_REINDEX:
+          $this->raiseSearchReindexIssue();
+          break;
 
+        case PhabricatorConfigManualActivity::TYPE_IDENTITIES:
+          $this->raiseRebuildIdentitiesIssue();
+          break;
+
+        default:
+      }
+    }
+  }
+
+  private function raiseSearchReindexIssue() {
     $activity_name = pht('Rebuild Search Index');
     $activity_summary = pht(
       'The search index algorithm has been updated and the index needs '.
@@ -60,16 +71,76 @@ final class PhabricatorManualActivitySetupCheck
     $message[] = phutil_tag(
       'pre',
       array(),
-        (string)csprintf('phabricator/ $ ./bin/config done %R', $type));
+      'phabricator/ $ ./bin/config done reindex');
 
     $activity_message = phutil_implode_html("\n\n", $message);
 
-      $this->newIssue('manual.'.$type)
+    $this->newIssue('manual.reindex')
+      ->setName($activity_name)
+      ->setSummary($activity_summary)
+      ->setMessage($activity_message);
+  }
+
+  private function raiseRebuildIdentitiesIssue() {
+    $activity_name = pht('Rebuild Repository Identities');
+    $activity_summary = pht(
+      'The mapping from VCS users to Phabricator users has changed '.
+      'and must be rebuilt.');
+
+    $message = array();
+
+    $message[] = pht(
+      'The way Phabricator attributes VCS activity to Phabricator users '.
+      'has changed. There is a new indirection layer between the strings '.
+      'that appear as VCS authors and committers (such as "John Developer '.
+      '<johnd@bigcorp.com>") and the Phabricator user that gets associated '.
+      'with VCS commits. This is to support situations where users '.
+      'are incorrectly associated with commits by Phabricator making bad '.
+      'guesses about the identity of the corresponding Phabricator user. '.
+      'This also helps with situations where existing repositories are '.
+      'imported without having created accounts for all the committers to '.
+      'that repository. Until you rebuild these repository identities, you '.
+      'are likely to encounter problems with future Phabricator features '.
+      'which will rely on the existence of these identities.');
+
+    $message[] = pht(
+      'You can rebuild repository identities while Phabricator is running.');
+
+    $message[] = pht(
+      'To rebuild identities, run this command:');
+
+    $message[] = phutil_tag(
+      'pre',
+      array(),
+      (string)csprintf(
+        'phabricator/ $ ./bin/repository rebuild-identities --all'));
+
+    $message[] = pht(
+      'You can find more information about this new identity mapping '.
+      'here: %s',
+      phutil_tag(
+        'a',
+        array(
+          'href' => 'https://phurl.io/u/repoIdentities',
+          'target' => '_blank',
+        ),
+        'https://phurl.io/u/repoIdentities'));
+
+    $message[] = pht(
+      'After rebuilding repository identities, run this command to clear '.
+      'this setup warning:');
+
+    $message[] = phutil_tag(
+      'pre',
+      array(),
+      'phabricator/ $ ./bin/config done identities');
+
+    $activity_message = phutil_implode_html("\n\n", $message);
+
+    $this->newIssue('manual.identities')
       ->setName($activity_name)
       ->setSummary($activity_summary)
       ->setMessage($activity_message);
   }
 
 }
-
-}

src/applications/config/storage/PhabricatorConfigManualActivity.php

@@ -7,6 +7,8 @@ final class PhabricatorConfigManualActivity
   protected $parameters = array();
 
   const TYPE_REINDEX = 'reindex';
+  const TYPE_IDENTITIES = 'identities';
+
 
   protected function getConfiguration() {
     return array(