Add http keepalive setting for more efficient local testing

src/client-factory.js

@@ -9,7 +9,7 @@ module.exports = function clientFactory (config, creds, region) {
   async function client (params = {}) {
     let selectedRegion = params.region || region
     try {
-      return await request(params, creds, selectedRegion)
+      return await request(params, creds, selectedRegion, config)
     }
     catch (err) {
       errorHandler(err)
@@ -60,7 +60,7 @@ module.exports = function clientFactory (config, creds, region) {
             let result = await method.request(params)
             let metadata = { service, name }
             try {
-              return await request({ ...params, ...result }, creds, selectedRegion, metadata)
+              return await request({ ...params, ...result }, creds, selectedRegion, config, metadata)
             }
             catch (err) {
               if (method.error) {

src/index.js

@@ -10,6 +10,7 @@ let clientFactory = require('./client-factory')
  * @param {string} [config.region] AWS service region (e.g. `us-west-1`); can be overridden per request
  * @param {string} [config.profile] Credential profile name to use
  * @param {boolean} [config.autoloadPlugins=true] Attempt to automatically load aws-lite plugins
+ * @param {boolean} [config.keepAlive=true] Disable Node.js's connection keepalive, helpful for local-only testing
  *
  * @returns {Promise<function>} Client async function
  */

src/request.js

@@ -1,7 +1,7 @@
 let https = require('https')
 let aws4 = require('aws4')
 
-module.exports = function request (params, creds, region, metadata) {
+module.exports = function request (params, creds, region, config, metadata) {
   return new Promise((resolve, reject) => {
     params.path = params.path || params.endpoint
 
@@ -17,6 +17,10 @@ module.exports = function request (params, creds, region, metadata) {
     }
 
     let options = aws4.sign({ ...params, region }, creds)
+
+    // Disable keep-alive locally (or wait Node's default 5s for sockets to time out)
+    options.agent = new https.Agent({ keepAlive: config.keepAlive ?? useAWS() })
+
     let req = https.request(options, res => {
       let data = []
       let { headers = {}, statusCode } = res
@@ -37,3 +41,16 @@ module.exports = function request (params, creds, region, metadata) {
     req.end(options.body || '')
   })
 }
+
+// Probably this is going to need some refactoring in Arc 11
+// Certainly it is not reliable in !Arc local Lambda emulation
+let nonLocalEnvs = [ 'staging', 'production' ]
+function useAWS () {
+  let { ARC_ENV, ARC_LOCAL, ARC_SANDBOX } = process.env
+  // Testing is always local
+  if (ARC_ENV === 'testing') return false
+  // Local, but using AWS resources
+  if (nonLocalEnvs.includes(ARC_ENV) && ARC_SANDBOX && !ARC_LOCAL) return false
+  // Assumed to be AWS
+  return true
+}