Better handling of log file failures (#9539)

Fix issues when APP_LOG is empty, unwritable , or pointed at a directory.
APP_LOG takes precedence over $config['log_file'] now.

DO NOT DELETE THIS TEXT

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app/Checks.php

@@ -220,6 +220,18 @@ class Checks
             $commands[] = "usermod -a -G $group $current_user";
         }
 
+        // check for invalid log setting
+        $log_file = config('app.log') ?: Config::get('log_file', base_path('logs/librenms.log'));
+        if (!is_file($log_file) || !is_writable($log_file)) {
+            // override for proper error output
+            $dirs = [$log_file];
+            $install_dir = $log_file;
+            $commands = [
+                '<h3>Cannot write to log file: &quot;' . $log_file . '&quot;</h3>',
+                'Make sure it exists and is writable, or change your LOG_DIR setting.'
+            ];
+        }
+
         // selinux:
         $commands[] = '<h4>If using SELinux you may also need:</h4>';
         foreach ($dirs as $dir) {
@@ -230,6 +242,7 @@ class Checks
         // use pre-compiled template because we probably can't compile it.
         $template = file_get_contents(base_path('resources/views/errors/static/file_permissions.html'));
         $content = str_replace('!!!!CONTENT!!!!', '<p>' . implode('</p><p>', $commands) . '</p>', $template);
+        $content = str_replace('!!!!LOG_FILE!!!!', $log_file, $content);
 
         return SymfonyResponse::create($content);
     }

app/Providers/AppServiceProvider.php

@@ -18,7 +18,6 @@ class AppServiceProvider extends ServiceProvider
      * Bootstrap any application services.
      *
      * @return void
-     * @throws DatabaseConnectException caught by App\Exceptions\Handler and displayed to the user
      */
     public function boot()
     {
@@ -28,9 +27,9 @@ class AppServiceProvider extends ServiceProvider
         // load config
         Config::load();
 
-        // direct log output to librenms.log
+        // replace early boot logging redirect log to config location, unless APP_LOG is set
         Log::getMonolog()->popHandler(); // remove existing errorlog logger
-        Log::useFiles(Config::get('log_file', base_path('logs/librenms.log')), 'error');
+        Log::useFiles(config('app.log') ?: Config::get('log_file', base_path('logs/librenms.log')), 'error');
 
         // Blade directives (Yucky because of < L5.5)
         Blade::directive('config', function ($key) {

bootstrap/app.php

@@ -42,8 +42,8 @@ $app->singleton(
 );
 
 $app->configureMonologUsing(function (Monolog\Logger $logger) use ($app) {
-    $path = $app->basePath(config('app.log'));
-    $logger->pushHandler(new \Monolog\Handler\StreamHandler($path));
+    $path = config('app.log') ?: $app->basePath('logs/librenms.log');
+    $logger->pushHandler(new \Monolog\Handler\StreamHandler($path, \Monolog\Logger::toMonologLevel(config('app.log_level', 'debug'))));
 });
 
 /*

config/app.php

@@ -120,9 +120,9 @@ return [
     |
     */
 
-    'log' => env('APP_LOG', 'logs/librenms.log'),  // log to the default file, until boot
+    'log' => env('APP_LOG'),  // log file to write to
 
-    'log_level' => env('APP_LOG_LEVEL', 'debug'),
+    'log_level' => env('APP_LOG_LEVEL', 'error'),
 
     /*
     |--------------------------------------------------------------------------

resources/views/errors/file_permissions.blade.php

@@ -10,7 +10,4 @@
     @foreach($commands as $command)
         <p>{{ $command }}</p>
     @endforeach
-    <hr class="separator"/>
-
-    <p>@lang("If that doesn't fix the issue. You can find how to get help at") <a href="https://docs.librenms.org/Support">https://docs.librenms.org/Support</a>.</p>
 @endsection

resources/views/errors/static/file_permissions.html

@@ -70,6 +70,7 @@
     !!!!CONTENT!!!!
 
     <hr class="separator"/>
+    <p>Check your log for more details.  (<i>!!!!LOG_FILE!!!!</i>)</p>
 
     <p>If that doesn't fix the issue. You can find how to get help at <a href="https://docs.librenms.org/Support">https://docs.librenms.org/Support</a>.</p>
 </div>

resources/views/layouts/error.blade.php

@@ -68,6 +68,7 @@
     @yield('content')
 
     <hr class="separator"/>
+    <p>@lang("Check your log for more details.") ({{ $log_file ?: 'librenms.log' }})</p>
 
     <p>@lang("If you need additional help, you can find how to get help at") <a href="https://docs.librenms.org/Support">https://docs.librenms.org/Support</a>.</p>
 </div>