Better stacktrace and fix problem on async jobs failing response

src/ApiException.js

@@ -18,7 +18,7 @@ export default function ApiException(
   }
 
   this.body = body;
-  this.headers = response.headers.raw();
+  this.headers = response.headers ? response.headers.raw() : {};
   this.statusCode = response.status;
   this.statusText = response.statusText;
   this.requestUrl = url;

src/Client.js

@@ -12,7 +12,7 @@ function queryString(query) {
 
 export default class Client {
   constructor(token, extraHeaders, baseUrl) {
-    this.baseUrl = baseUrl;
+    this.baseUrl = baseUrl.replace(/\/$/, '');
     this.token = token;
     this.extraHeaders = extraHeaders;
   }
@@ -67,10 +67,13 @@ export default class Client {
   buildFetchRequest(method, url, params, body, extraOptions) {
     const options = {
       method,
-      body: body && JSON.stringify(body, undefinedToNull),
       ...(extraOptions || {}),
     };
 
+    if (body) {
+      options.body = JSON.stringify(body, undefinedToNull);
+    }
+
     const headers = {
       ...this.defaultHeaders(),
       ...this.extraHeaders,
@@ -81,7 +84,7 @@ export default class Client {
 
     return {
       url: this.buildUrl(url, params),
-      options: { options, ...headers },
+      options: { ...options, headers },
     };
   }
 

src/InvalidApiRequestException.js

@@ -0,0 +1,10 @@
+export default function InvalidApiRequestException(message, preCallStack) {
+  if ('captureStackTrace' in Error) {
+    Error.captureStackTrace(this, InvalidApiRequestException);
+  } else {
+    this.stack = new Error().stack;
+  }
+
+  this.message = message;
+  this.stack += `\nCaused By:\n${preCallStack}`;
+}

src/utils/generateClient.js

@@ -7,6 +7,7 @@ import serializeJsonApi from './serializeJsonApi';
 import RawClient from '../Client';
 import fetchAllPages from './fetchAllPages';
 import ApiException from '../ApiException';
+import InvalidApiRequestException from '../InvalidApiRequestException';
 import wait from './wait';
 
 const identityRegexp = /\{\(.*?definitions%2F(.*?)%2Fdefinitions%2Fidentity\)}/g;
@@ -206,11 +207,18 @@ export default function generateClient(subdomain, cache, extraMethods = {}) {
                   (link.method === 'PUT' || link.method === 'POST') &&
                   serializeRequest
                 ) {
-                  body = serializeJsonApi(
-                    body,
-                    link,
-                    link.method === 'PUT' && lastUrlId,
-                  );
+                  try {
+                    body = serializeJsonApi(
+                      body,
+                      link,
+                      link.method === 'PUT' && lastUrlId,
+                    );
+                  } catch (e) {
+                    throw new InvalidApiRequestException(
+                      e.message,
+                      preCallStack,
+                    );
+                  }
                 }
 
                 if (link.method === 'POST') {