Add a very basic cache status page

Summary:
Ref T5501. This is just getting version detection and availability right, probably.

Eventually, this will get lifted up a bit and "$remedy" will turn into setup issues (or maybe one setup issue saying "your cache setup is messed up, click here to understand why").

Test Plan:
{F362935}

I intend to shove these up to production one-by-one since production is APC and local is Opcache + APCu.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T5501

Differential Revision: https://secure.phabricator.com/D12314

src/applications/config/controller/PhabricatorConfigCacheController.php

@@ -0,0 +1,172 @@
+<?php
+
+final class PhabricatorConfigCacheController
+  extends PhabricatorConfigController {
+
+  public function handleRequest(AphrontRequest $request) {
+    $viewer = $this->getViewer();
+
+    $nav = $this->buildSideNavView();
+    $nav->selectFilter('cache/');
+
+    $title = pht('Cache Status');
+
+    $crumbs = $this
+      ->buildApplicationCrumbs()
+      ->addTextCrumb(pht('Cache Status'));
+
+    $nav->setCrumbs($crumbs);
+
+    list($remedy, $properties) = $this->getProperties();
+
+    $property_list = id(new PHUIPropertyListView());
+    foreach ($properties as $property) {
+      list($name, $value) = $property;
+      $property_list->addProperty($name, $value);
+    }
+
+
+    $box = id(new PHUIObjectBoxView())
+      ->setFormErrors($remedy)
+      ->setHeaderText(pht('Cache'))
+      ->addPropertyList($property_list);
+
+    $nav->appendChild($box);
+
+    return $this->buildApplicationPage(
+      $nav,
+      array(
+        'title' => $title,
+      ));
+  }
+
+  private function getProperties() {
+    $remedy = array();
+
+    $properties = array();
+
+    // NOTE: If APCu is installed, it reports that APC is installed.
+    if (extension_loaded('apc') && !extension_loaded('apcu')) {
+      $cache_installed = true;
+      $cache_name = pht('APC');
+      $cache_version = phpversion('apc');
+      $cache_enabled = (bool)ini_get('apc.enabled');
+      if (!$cache_enabled) {
+        $remedy[] = pht('Enable APC');
+      }
+      $datacache_installed = true;
+      $datacache_name = pht('APC User Cache');
+      $datacache_version = phpversion('apc');
+      $datacache_enabled = true;
+    } else {
+      if (extension_loaded('Zend OPcache')) {
+        $cache_installed = true;
+        $cache_name = pht('Zend Opcache');
+        $cache_enabled = (bool)ini_get('opcache.enable');
+        $cache_version = phpversion('Zend OPcache');
+        if (!$cache_enabled) {
+          $remedy[] = pht('Enable Opcache.');
+        }
+      } else {
+        if (version_compare(phpversion(), '5.5', '>=')) {
+          $remedy[] = pht('Install OPcache.');
+        } else {
+          $remedy[] = pht('Install APC.');
+        }
+
+        $cache_installed = false;
+        $cache_name = pht('None');
+        $cache_enabled = false;
+        $cache_version = null;
+      }
+
+      if (extension_loaded('apcu')) {
+        $datacache_installed = true;
+        $datacache_name = pht('APCu');
+        $datacache_version = phpversion('apcu');
+        $datacache_enabled = (bool)ini_get('apc.enabled');
+      } else {
+        if (version_compare(phpversion(), '5.5', '>=')) {
+          $remedy[] = pht('Install APCu.');
+        } else {
+          // We already suggested installing APC above.
+        }
+
+        $datacache_installed = false;
+        $datacache_name = pht('None');
+        $datacache_version = null;
+        $datacache_enabled = false;
+      }
+    }
+
+    if ($cache_installed) {
+      $cache_property = $this->renderYes($cache_name);
+    } else {
+      $cache_property = $this->renderNo($cache_name);
+    }
+
+    if ($cache_enabled) {
+      $cache_enabled_property = $this->renderYes(pht('Enabled'));
+    } else {
+      $cache_enabled_property = $this->renderNo(pht('Not Enabled'));
+    }
+
+    $properties[] = array(pht('Opcode Cache'), $cache_property);
+    $properties[] = array(pht('Enabled'), $cache_enabled_property);
+    if ($cache_version) {
+      $properties[] = array(
+        pht('Version'),
+        $this->renderInfo($cache_version),
+      );
+    }
+
+    if ($datacache_installed) {
+      $datacache_property = $this->renderYes($datacache_name);
+    } else {
+      $datacache_property = $this->renderNo($datacache_name);
+    }
+
+    if ($datacache_enabled) {
+      $datacache_enabled_property = $this->renderYes(pht('Enabled'));
+    } else {
+      $datacache_enabled_property = $this->renderNo(pht('Not Enabled'));
+    }
+
+    $properties[] = array(pht('Data Cache'), $datacache_property);
+    $properties[] = array(pht('Enabled'), $datacache_enabled_property);
+    if ($datacache_version) {
+      $properties[] = array(
+        pht('Version'),
+        $this->renderInfo($datacache_version),
+      );
+    }
+
+
+    return array($remedy, $properties);
+  }
+
+  private function renderYes($info) {
+    return array(
+      id(new PHUIIconView())->setIconFont('fa-check', 'green'),
+      ' ',
+      $info,
+    );
+  }
+
+  private function renderNo($info) {
+    return array(
+      id(new PHUIIconView())->setIconFont('fa-times-circle', 'red'),
+      ' ',
+      $info,
+    );
+  }
+
+  private function renderInfo($info) {
+    return array(
+      id(new PHUIIconView())->setIconFont('fa-info-circle', 'grey'),
+      ' ',
+      $info,
+    );
+  }
+
+}