From d54c14c644448a8ad35c0b02192332acd5364e9e Mon Sep 17 00:00:00 2001
From: epriestley <git@epriestley.com>
Date: Fri, 25 Nov 2016 13:56:08 -0800
Subject: [PATCH] If InnoDB FULLTEXT is available, use it for for fulltext
 indexes

Summary: Ref T11741. I'll wait until the release cut to land this; it just adds a test for InnoDB FULLTEXT being available instead of always returning `false`.

Test Plan:
  - Ran with InnoDB fulltext locally for a day and a half without issues.
  - Ran `bin/storage upgrade`, saw it detect InnoDB fulltext.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11741

Differential Revision: https://secure.phabricator.com/D16946
---
 .../document/PhabricatorSearchDocument.php    | 27 +++++++++++++++----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/src/applications/search/storage/document/PhabricatorSearchDocument.php b/src/applications/search/storage/document/PhabricatorSearchDocument.php
index aee47cb9d3..424a3ccd9b 100644
--- a/src/applications/search/storage/document/PhabricatorSearchDocument.php
+++ b/src/applications/search/storage/document/PhabricatorSearchDocument.php
@@ -40,15 +40,15 @@ final class PhabricatorSearchDocument extends PhabricatorSearchDAO {
   }
 
   public static function newQueryCompiler() {
-    $table = new self();
-    $conn = $table->establishConnection('r');
-
     $compiler = new PhutilSearchQueryCompiler();
 
     if (self::isInnoDBFulltextEngineAvailable()) {
       // The InnoDB fulltext boolean operators are always the same as the
       // default MyISAM operators, so we do not need to adjust the compiler.
     } else {
+      $table = new self();
+      $conn = $table->establishConnection('r');
+
       $operators = queryfx_one(
         $conn,
         'SELECT @@ft_boolean_syntax AS syntax');
@@ -61,8 +61,25 @@ final class PhabricatorSearchDocument extends PhabricatorSearchDAO {
   }
 
   public static function isInnoDBFulltextEngineAvailable() {
-    // For now, never consider this engine to be available.
-    return false;
+    static $available;
+
+    if ($available === null) {
+      $table = new self();
+      $conn = $table->establishConnection('r');
+
+      // If this system variable exists, we can use InnoDB fulltext. If it
+      // does not, this query will throw and we're stuck with MyISAM.
+      try {
+        queryfx_one(
+          $conn,
+          'SELECT @@innodb_ft_max_token_size');
+        $available = true;
+      } catch (AphrontQueryException $x) {
+        $available = false;
+      }
+    }
+
+    return $available;
   }
 
 }