refactor to not rely on babel

Author: dougmoscrop

.babelrc

@@ -1,9 +1,8 @@
 extends: eslint:recommended
-parser: babel-eslint
+
 rules:
   strict: 0
 
 env:
   node: true
   es6: true
-

.eslintrc

@@ -1,3 +1,5 @@
+'use strict';
+
 /**
  * A connection handler for Amazon ES.
  *
@@ -9,125 +11,116 @@
  * @class HttpConnector
  */
 
-import AWS from 'aws-sdk';
-import HttpConnector from 'elasticsearch/src/lib/connectors/http'
-import _ from 'elasticsearch/src/lib/utils';
-import zlib from 'zlib';
+const AWS = require('aws-sdk');
+const HttpConnector = require('elasticsearch/src/lib/connectors/http');
+const zlib = require('zlib');
 
 class HttpAmazonESConnector extends HttpConnector {
   constructor(host, config) {
     super(host, config);
-    const { protocol, port } = host;
+
+    const protocol = host.protocol;
+    const port = host.port;
     const endpoint = new AWS.Endpoint(host.host);
 
     if (protocol) endpoint.protocol = protocol.replace(/:?$/, ":");
     if (port) endpoint.port = port;
 
-    this.AWS = AWS;
     this.awsConfig = config.awsConfig || AWS.config;
     this.endpoint = endpoint;
     this.httpOptions = config.httpOptions || this.awsConfig.httpOptions;
+    this.httpClient = new AWS.NodeHttpClient();
   }
 
-  async request(params, cb) {
-    let incoming;
-    let timeoutId;
-    let request;
+  request(params, cb) {
+    const reqParams = this.makeReqParams(params);
+    const request = this.createRequest(params, reqParams);
+    const signer = new AWS.Signers.V4(request, 'es');
+
     let req;
     let status = 0;
     let headers = {};
-    let log = this.log;
     let response;
-    const AWS = this.AWS;
+    let incoming;
 
-    let reqParams = this.makeReqParams(params);
     // general clean-up procedure to run after the request
     // completes, has an error, or is aborted.
-    let cleanUp = _.bind(function (err) {
-      clearTimeout(timeoutId);
-
+    const cleanUp = (err) => {
       req && req.removeAllListeners();
       incoming && incoming.removeAllListeners();
 
-      if ((err instanceof Error) === false) {
-        err = void 0;
-      }
-
-      log.trace(params.method, reqParams, params.body, response, status);
-      if (err) {
+      this.log.trace(params.method, reqParams, params.body, response, status);
+      if (err instanceof Error) {
         cb(err);
       } else {
-        cb(err, response, status, headers);
+        cb(null, response, status, headers);
       }
-    }, this);
-
-    request = new AWS.HttpRequest(this.endpoint);
-
-    // copy across params
-    for (let p in reqParams) {
-      request[p] = reqParams[p];
-    }
-    request.region = this.awsConfig.region;
-    if (params.body) request.body = params.body;
-    if (!request.headers) request.headers = {};
-    request.headers['presigned-expires'] = false;
-    request.headers['Host'] = this.endpoint.host;
+    };
 
     // load creds
-    let CREDS;
-    try {
-      CREDS = await this.getAWSCredentials();
-
-      // Sign the request (Sigv4)
-      let signer = new AWS.Signers.V4(request, 'es');
-      signer.addAuthorization(CREDS, new Date());
-    } catch (e) {
-      if (e && e.message) e.message = `AWS Credentials error: ${e.message}`;
-      cleanUp(e);
-      return () => {};
-    }
-
-    let send = new AWS.NodeHttpClient();
-    req = send.handleRequest(request, this.httpOptions, function (_incoming) {
-      incoming = _incoming;
-      status = incoming.statusCode;
-      headers = incoming.headers;
-      response = '';
-
-      let encoding = (headers['content-encoding'] || '').toLowerCase();
-      if (encoding === 'gzip' || encoding === 'deflate') {
-        incoming = incoming.pipe(zlib.createUnzip());
-      }
-
-      incoming.setEncoding('utf8');
-      incoming.on('data', function (d) {
-        response += d;
+    return this.getAWSCredentials()
+      .then(creds => {
+        // Sign the request (Sigv4)
+        signer.addAuthorization(creds, new Date());
+
+        req = this.httpClient.handleRequest(request, this.httpOptions, function (_incoming) {
+          incoming = _incoming;
+          status = incoming.statusCode;
+          headers = incoming.headers;
+          response = '';
+
+          let encoding = (headers['content-encoding'] || '').toLowerCase();
+          if (encoding === 'gzip' || encoding === 'deflate') {
+            incoming = incoming.pipe(zlib.createUnzip());
+          }
+
+          incoming.setEncoding('utf8');
+          incoming.on('data', function (d) {
+            response += d;
+          });
+
+          incoming.on('error', cleanUp);
+          incoming.on('end', cleanUp);
+        }, cleanUp);
+
+        req.on('error', cleanUp);
+
+        req.setNoDelay(true);
+        req.setSocketKeepAlive(true);
+      })
+      .then(() => {
+        return () => req.abort();
+      })
+      .catch(e => {
+        if (e && e.message) e.message = `AWS Credentials error: ${e.message}`;
+        cleanUp(e);
+        return () => {};
       });
-
-      incoming.on('error', cleanUp);
-      incoming.on('end', cleanUp);
-    }, cleanUp);
-
-    req.on('error', cleanUp);
-
-    req.setNoDelay(true);
-    req.setSocketKeepAlive(true);
-
-    return function () {
-      req.abort();
-    };
   }
 
   getAWSCredentials() {
-    const { awsConfig } = this;
-
     return new Promise((resolve, reject) => {
-      awsConfig.getCredentials((err, creds) => {
+      this.awsConfig.getCredentials((err, creds) => {
         if (err) return reject(err);
         return resolve(creds);
       });
     });
   }
+
+  createRequest(params, reqParams) {
+    const request = new AWS.HttpRequest(this.endpoint);
+
+    // copy across params
+    Object.assign(request, reqParams);
+
+    request.region = this.awsConfig.region;
+    if (params.body) request.body = params.body;
+    if (!request.headers) request.headers = {};
+    request.headers['presigned-expires'] = false;
+    request.headers['Host'] = this.endpoint.host;
+
+    return request;
+  }
 }
 
 module.exports = HttpAmazonESConnector;