Handle HTTP 400 response from LXD for better handling of error messages

Without this you end up with getting json strings that get truncated,
nobody wants to try reading that.

Author: turtle0x1

src/Exception/BadRequestException.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace Opensaucesystems\Lxd\Exception;
+
+use Http\Client\Exception\HttpException;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+class BadRequestException extends HttpException
+{
+    private $fallbackMessage = "LXD produced an error state but we could not parse the response";
+
+    public function __construct(RequestInterface $request, ResponseInterface $response, \Exception $previous = null)
+    {
+        $content = json_decode($response->getBody()->getContents(), true);
+
+        $message = json_last_error() !== 0 ? $this->fallbackMessage : $content["error"];
+
+        parent::__construct($message, $request, $response, $previous);
+    }
+}

src/HttpClient/Plugin/LxdExceptionThower.php

@@ -6,6 +6,7 @@
 use Psr\Http\Message\RequestInterface;
 use Psr\Http\Message\ResponseInterface;
 use Http\Client\Exception\HttpException;
+use Opensaucesystems\Lxd\Exception\BadRequestException;
 use Opensaucesystems\Lxd\Exception\OperationException;
 use Opensaucesystems\Lxd\Exception\AuthenticationFailedException;
 use Opensaucesystems\Lxd\Exception\NotFoundException;
@@ -23,25 +24,29 @@ class LxdExceptionThower implements Plugin
     public function handleRequest(RequestInterface $request, callable $next, callable $first)
     {
         $promise = $next($request);
-        
+
         return $promise->then(function (ResponseInterface $response) use ($request) {
             return $response;
         }, function (\Exception $e) use ($request) {
             if (get_class($e) === HttpException::class) {
                 $response = $e->getResponse();
 
+                if (400 === $response->getStatusCode()) {
+                    throw new BadRequestException($request, $response, $e);
+                }
+
                 if (401 === $response->getStatusCode()) {
                     throw new OperationException($request, $response, $e);
                 }
 
                 if (403 === $response->getStatusCode()) {
                     throw new AuthenticationFailedException($request, $response, $e);
                 }
-                
+
                 if (404 === $response->getStatusCode()) {
                     throw new NotFoundException($request, $response, $e);
                 }
-                
+
                 if (409 === $response->getStatusCode()) {
                     throw new ConflictException($request, $response, $e);
                 }