FIX: Removed unnecessary database_is_ready call.

This shaves about 45ms from every request (PHP 7.1 on a 2013 rMBP), 
cutting down execution time of a “hello world” controller by about 33%.

database_is_ready is still used in dev/build and ?flush=1 to stop people
from people bypassing security by DOSing the database or otherwise
forcing a DatabaseException

src/Security/AuthenticationMiddleware.php

@@ -7,6 +7,7 @@ use SilverStripe\Control\HTTPResponse;
 use SilverStripe\Control\Middleware\HTTPMiddleware;
 use SilverStripe\Core\Config\Configurable;
 use SilverStripe\ORM\ValidationException;
+use SilverStripe\ORM\Connect\DatabaseException;
 
 class AuthenticationMiddleware implements HTTPMiddleware
 {
@@ -44,7 +45,6 @@ class AuthenticationMiddleware implements HTTPMiddleware
      */
     public function process(HTTPRequest $request, callable $delegate)
     {
-        if (Security::database_is_ready()) {
         try {
             $this
                 ->getAuthenticationHandler()
@@ -54,7 +54,8 @@ class AuthenticationMiddleware implements HTTPMiddleware
                 "Bad log-in details: " . $e->getMessage(),
                 400
             );
-            }
+        } catch (DatabaseException $e) {
+            // Database isn't ready, carry on.
         }
 
         return $delegate($request);

src/Security/BasicAuth.php

@@ -10,6 +10,7 @@ use SilverStripe\Control\HTTPResponse_Exception;
 use SilverStripe\Core\Config\Configurable;
 use SilverStripe\Dev\Debug;
 use SilverStripe\Security\MemberAuthenticator\MemberAuthenticator;
+use SilverStripe\ORM\Connect\DatabaseException;
 
 /**
  * Provides an interface to HTTP basic authentication.
@@ -72,7 +73,7 @@ class BasicAuth
         $permissionCode = null,
         $tryUsingSessionLogin = true
     ) {
-        if (!Security::database_is_ready() || (Director::is_cli() && static::config()->get('ignore_cli'))) {
+        if ((Director::is_cli() && static::config()->get('ignore_cli'))) {
             return true;
         }
 
@@ -94,6 +95,7 @@ class BasicAuth
 
         $member = null;
 
+        try {
             if ($request->getHeader('PHP_AUTH_USER') && $request->getHeader('PHP_AUTH_PW')) {
                 /** @var MemberAuthenticator $authenticator */
                 $authenticators = Security::singleton()->getApplicableAuthenticators(Authenticator::LOGIN);
@@ -108,6 +110,10 @@ class BasicAuth
                     }
                 }
             }
+        } catch (DatabaseException $e) {
+            // Database isn't ready, let people in
+            return true;
+        }
 
         if ($member instanceof Member) {
             Security::setCurrentUser($member);

src/Security/MemberAuthenticator/CookieAuthenticationHandler.php

@@ -107,8 +107,7 @@ class CookieAuthenticationHandler implements AuthenticationHandler
         $uidAndToken = Cookie::get($this->getTokenCookieName());
         $deviceID = Cookie::get($this->getDeviceCookieName());
 
-        // @todo Consider better placement of database_is_ready test
-        if ($deviceID === null || strpos($uidAndToken, ':') === false || !Security::database_is_ready()) {
+        if ($deviceID === null || strpos($uidAndToken, ':') === false) {
             return null;
         }