Add basic API error handling for HTTP client

client/src/api/admin.js

@@ -13,11 +13,11 @@ export const getChildPages = (id, options = {}) => {
     url += `&${options.filter}`;
   }
 
-  return get(url);
+  return get(url).then(res => res.body);
 };
 
 export const getPage = (id) => {
   const url = `${ADMIN_API.PAGES}${id}/`;
 
-  return get(url);
+  return get(url).then(res => res.body);
 };

client/src/api/client.js

@@ -1,9 +1,13 @@
+import _ from 'lodash';
+
 const fetch = global.fetch;
 
 // fetch wrapper for JSON APIs.
 export const get = (url) => {
-  const headers = new Headers();
-  headers.append('Content-Type', 'application/json');
+  const headers = new Headers({
+    'Accept': 'application/json',
+    'Content-Type': 'application/json',
+  });
 
   const options = {
     credentials: 'same-origin',
@@ -12,5 +16,23 @@ export const get = (url) => {
   };
 
   return fetch(url, options)
-    .then(response => response.json());
+    .then((res) => {
+      const response = {
+        status: res.status,
+        statusText: res.statusText,
+        headers: res.headers
+      };
+
+      let ret;
+      if (response.status >= 200 && response.status < 300) {
+        ret = res.json().then(json => _.assign(response, { body: json }));
+      } else {
+        ret =  res.text().then((text) => {
+          const err = _.assign(new Error(response.statusText), response, { body: text });
+          throw err;
+        });
+      }
+
+      return ret;
+    });
 };