Remove xpack usage module (#21099)

x-pack/plugins/xpack_main/server/routes/api/v1/xpack_usage.js

@@ -1,54 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License;
- * you may not use this file except in compliance with the Elastic License.
- */
-
-import { wrap as wrapError } from 'boom';
-
-const getClusterUuid = async callCluster => {
-  const { cluster_uuid: uuid } = await callCluster('info', { filterPath: 'cluster_uuid', });
-  return uuid;
-};
-
-/*
- * @return {Object} data from usage stats collectors registered with Monitoring CollectorSet
- * @throws {Error} if the Monitoring CollectorSet is not ready
- */
-const getUsage = async (callCluster, server) => {
-  const { collectorSet } = server.usage;
-  const usage = await collectorSet.bulkFetchUsage(callCluster);
-  const usageObject = collectorSet.toObject(usage);
-  return collectorSet.toApiFieldNames(usageObject);
-};
-
-export function xpackUsageRoute(server) {
-  server.route({
-    path: '/api/_xpack/usage',
-    method: 'GET',
-    async handler(req, reply) {
-      const { server } = req;
-      const { callWithRequest } = server.plugins.elasticsearch.getCluster('data');
-      const callCluster = (...args) => callWithRequest(req, ...args); // All queries from HTTP API must use authentication headers from the request
-
-      try {
-        const [ clusterUuid, xpackUsage ] = await Promise.all([
-          getClusterUuid(callCluster),
-          getUsage(callCluster, server),
-        ]);
-
-        reply({
-          cluster_uuid: clusterUuid,
-          ...xpackUsage
-        });
-      } catch(err) {
-        req.log(['error'], err); // FIXME doesn't seem to log anything useful if ES times out
-        if (err.isBoom) {
-          reply(err);
-        } else {
-          reply(wrapError(err, err.statusCode, err.message));
-        }
-      }
-    }
-  });
-}