callWithRequest should pass the context that the API method would get…

… when called normally instead of assuming client is the context for everything

src/plugins/elasticsearch/lib/call_with_request.js

@@ -2,15 +2,21 @@ const _ = require('lodash');
 const Promise = require('bluebird');
 const Boom = require('boom');
 const getBasicAuthRealm = require('./get_basic_auth_realm');
+const toPath = require('lodash/internal/toPath');
 
 module.exports = (client) => {
   return (req, endpoint, params = {}) => {
     if (req.headers.authorization) {
       _.set(params, 'headers.authorization', req.headers.authorization);
     }
-    const api = _.get(client, endpoint);
+    const path = toPath(endpoint);
+    const api = _.get(client, path);
+    let apiContext = _.get(client, path.slice(0, -1));
+    if (_.isEmpty(apiContext)) {
+      apiContext = client;
+    }
     if (!api) throw new Error(`callWithRequest called with an invalid endpoint: ${endpoint}`);
-    return api.call(client, params)
+    return api.call(apiContext, params)
       .catch((err) => {
         if (err.status === 401) {
           // TODO: The err.message is temporary until we have support for getting headers in the client.