initial commit. phase 1 complete

frontend/node_modules/openid-client/lib/helpers/decode_jwt.js

@@ -0,0 +1,27 @@
+const base64url = require('./base64url');
+
+module.exports = (token) => {
+  if (typeof token !== 'string' || !token) {
+    throw new TypeError('JWT must be a string');
+  }
+
+  const { 0: header, 1: payload, 2: signature, length } = token.split('.');
+
+  if (length === 5) {
+    throw new TypeError('encrypted JWTs cannot be decoded');
+  }
+
+  if (length !== 3) {
+    throw new Error('JWTs must have three components');
+  }
+
+  try {
+    return {
+      header: JSON.parse(base64url.decode(header)),
+      payload: JSON.parse(base64url.decode(payload)),
+      signature,
+    };
+  } catch (err) {
+    throw new Error('JWT is malformed');
+  }
+};