Manually UTF-8 then B64 encode credentials.

btoa only supports 8-bit characters.

Author: oampo

package.json

@@ -6,6 +6,7 @@
     "react-scripts": "0.9.5"
   },
   "dependencies": {
+    "base64-js": "^1.2.1",
     "jwt-decode": "^2.2.0",
     "react": "^15.5.4",
     "react-dom": "^15.5.4",
@@ -14,6 +15,7 @@
     "redux": "^3.6.0",
     "redux-form": "^6.6.3",
     "redux-thunk": "^2.2.0",
+    "text-encoding": "^0.6.4",
     "validator": "^7.0.0"
   },
   "scripts": {

src/actions/auth.js

@@ -1,5 +1,7 @@
 import jwtDecode from 'jwt-decode';
 import {SubmissionError} from 'redux-form';
+import {fromByteArray} from 'base64-js';
+import {TextEncoder} from 'text-encoding';
 
 import {API_BASE_URL} from '../config';
 import {normalizeResponseErrors} from './utils';
@@ -17,6 +19,13 @@ export const setCurrentUser = currentUser => ({
     currentUser
 });
 
+// Encode a JS string as Base-64 encoded UTF-8
+const base64EncodingUTF8 = str => {
+    const encoded = new TextEncoder('utf-8').encode(str);
+    const b64Encoded = fromByteArray(encoded);
+    return b64Encoded;
+};
+
 // Stores the auth token in state and localStorage, and decodes and stores
 // the user data stored in the token
 const storeAuthInfo = (authToken, dispatch) => {
@@ -29,7 +38,7 @@ const storeAuthInfo = (authToken, dispatch) => {
 export const login = (username, password) => dispatch => {
     // Base64 encode the string username:password, used in the basic
     // auth field
-    const token = btoa(`${username}:${password}`);
+    const token = base64EncodingUTF8(`${username}:${password}`);
     return (
         fetch(`${API_BASE_URL}/auth/login`, {
             method: 'POST',

yarn.lock

@@ -889,6 +889,10 @@ base64-js@^1.0.2:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.2.0.tgz#a39992d723584811982be5e290bb6a53d86700f1"
 
+base64-js@^1.2.1:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.2.1.tgz#a91947da1f4a516ea38e5b4ec0ec3773675e0886"
+
 [email protected]:
   version "0.5.3"
   resolved "https://registry.yarnpkg.com/batch/-/batch-0.5.3.tgz#3f3414f380321743bfc1042f9a83ff1d5824d464"
@@ -4958,6 +4962,10 @@ test-exclude@^3.3.0:
     read-pkg-up "^1.0.1"
     require-main-filename "^1.0.1"
 
+text-encoding@^0.6.4:
+  version "0.6.4"
+  resolved "https://registry.yarnpkg.com/text-encoding/-/text-encoding-0.6.4.tgz#e399a982257a276dae428bb92845cb71bdc26d19"
+
 text-table@~0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/text-table/-/text-table-0.2.0.tgz#7f5ee823ae805207c00af2df4a84ec3fcfa570b4"