Merge pull request #2730 from Icinga/bugfix/invalid-icinga-2-api-response-2728

Handle invalid Icinga 2 API response types

library/Icinga/Exception/Json/JsonDecodeException.php

@@ -0,0 +1,11 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Exception\Json;
+
+/**
+ * Exception thrown by {@link \Icinga\Util\Json::decode()} on failure
+ */
+class JsonDecodeException extends JsonException
+{
+}

library/Icinga/Exception/Json/JsonEncodeException.php

@@ -0,0 +1,11 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Exception\Json;
+
+/**
+ * Exception thrown by {@link \Icinga\Util\Json::encode()} on failure
+ */
+class JsonEncodeException extends JsonException
+{
+}

library/Icinga/Exception/Json/JsonException.php

@@ -0,0 +1,13 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Exception\Json;
+
+use Icinga\Exception\IcingaException;
+
+/**
+ * Exception thrown by {@link \Icinga\Util\Json} on failure
+ */
+abstract class JsonException extends IcingaException
+{
+}

library/Icinga/Util/Json.php

@@ -0,0 +1,80 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Util;
+
+use Icinga\Exception\Json\JsonDecodeException;
+use Icinga\Exception\Json\JsonEncodeException;
+
+/**
+ * Wrap {@link json_encode()} and {@link json_decode()} with error handling
+ */
+class Json
+{
+    /**
+     * {@link json_encode()} wrapper
+     *
+     * @param   mixed   $value
+     * @param   int     $options
+     * @param   int     $depth
+     *
+     * @return  string
+     * @throws  JsonEncodeException
+     */
+    public static function encode($value, $options = 0, $depth = 512)
+    {
+        $encoded = json_encode($value, $options, $depth);
+        if (json_last_error() !== JSON_ERROR_NONE) {
+            throw new JsonEncodeException('%s: %s', static::lastErrorMsg(), var_export($value, true));
+        }
+        return $encoded;
+    }
+
+    /**
+     * {@link json_decode()} wrapper
+     *
+     * @param   string  $json
+     * @param   bool    $assoc
+     * @param   int     $depth
+     * @param   int     $options
+     *
+     * @return  mixed
+     * @throws  JsonDecodeException
+     */
+    public static function decode($json, $assoc = false, $depth = 512, $options = 0)
+    {
+        $decoded = json_decode($json, $assoc, $depth, $options);
+        if (json_last_error() !== JSON_ERROR_NONE) {
+            throw new JsonDecodeException('%s: %s', static::lastErrorMsg(), var_export($json, true));
+        }
+        return $decoded;
+    }
+
+    /**
+     * {@link json_last_error_msg()} replacement for PHP < 5.5.0
+     *
+     * @return string
+     */
+    protected static function lastErrorMsg()
+    {
+        if (version_compare(PHP_VERSION, '5.5.0', '>=')) {
+            return json_last_error_msg();
+        }
+
+        // All possible error codes before PHP 5.5.0 (except JSON_ERROR_NONE)
+        switch (json_last_error()) {
+            case JSON_ERROR_DEPTH:
+                return 'Maximum stack depth exceeded';
+            case JSON_ERROR_STATE_MISMATCH:
+                return 'State mismatch (invalid or malformed JSON)';
+            case JSON_ERROR_CTRL_CHAR:
+                return 'Control character error, possibly incorrectly encoded';
+            case JSON_ERROR_SYNTAX:
+                return 'Syntax error';
+            case JSON_ERROR_UTF8:
+                return 'Malformed UTF-8 characters, possibly incorrectly encoded';
+            default:
+                return 'Unknown error';
+        }
+    }
+}

modules/monitoring/library/Monitoring/Command/Transport/ApiCommandTransport.php

@@ -4,6 +4,7 @@
 namespace Icinga\Module\Monitoring\Command\Transport;
 
 use Icinga\Application\Logger;
+use Icinga\Exception\Json\JsonDecodeException;
 use Icinga\Module\Monitoring\Command\IcingaApiCommand;
 use Icinga\Module\Monitoring\Command\IcingaCommand;
 use Icinga\Module\Monitoring\Command\Renderer\IcingaApiCommandRenderer;
@@ -193,12 +194,18 @@ class ApiCommandTransport implements CommandTransportInterface
             $this->getHost(),
             $this->getPort()
         );
-        $response = RestRequest::post($this->getUriFor($command->getEndpoint()))
+
-            ->authenticateWith($this->getUsername(), $this->getPassword())
+        try {
-            ->sendJson()
+            $response = RestRequest::post($this->getUriFor($command->getEndpoint()))
-            ->noStrictSsl()
+                ->authenticateWith($this->getUsername(), $this->getPassword())
-            ->setPayload($command->getData())
+                ->sendJson()
-            ->send();
+                ->noStrictSsl()
+                ->setPayload($command->getData())
+                ->send();
+        } catch (JsonDecodeException $e) {
+            throw new CommandTransportException('Got invalid JSON response from the Icinga 2 API: %s', $e->getMessage());
+        }
+
         if (isset($response['error'])) {
             throw new CommandTransportException(
                 'Can\'t send external Icinga command: %u %s',

modules/monitoring/library/Monitoring/Web/Rest/RestRequest.php

@@ -5,6 +5,7 @@ namespace Icinga\Module\Monitoring\Web\Rest;
 
 use Exception;
 use Icinga\Application\Logger;
+use Icinga\Util\Json;
 
 /**
  * REST Request
@@ -261,35 +262,6 @@ class RestRequest
             fclose($stream);
         }
 
-        $response = @json_decode($result, true);
+        return Json::decode($result, true);
-
-        if ($response === null) {
-            if (version_compare(PHP_VERSION, '5.5.0', '>=')) {
-                throw new Exception(json_last_error_msg());
-            } else {
-                switch (json_last_error()) {
-                    case JSON_ERROR_DEPTH:
-                        $msg = 'The maximum stack depth has been exceeded';
-                        break;
-                    case JSON_ERROR_CTRL_CHAR:
-                        $msg = 'Control character error, possibly incorrectly encoded';
-                        break;
-                    case JSON_ERROR_STATE_MISMATCH:
-                        $msg = 'Invalid or malformed JSON';
-                        break;
-                    case JSON_ERROR_SYNTAX:
-                        $msg = 'Syntax error';
-                        break;
-                    case JSON_ERROR_UTF8:
-                        $msg = 'Malformed UTF-8 characters, possibly incorrectly encoded';
-                        break;
-                    default:
-                        $msg = 'An error occured when parsing a JSON string';
-                }
-                throw new Exception($msg);
-            }
-        }
-
-        return $response;
     }
 }