Improved agent (#240)

* improves agent

- reverts spdy for now (causing issues with alias)
- sets up an agent pool of 4 max sockets with a 10s keep alive timeout
- better error handling and re-initialization

* improves agent

- reverts spdy for now (causing issues with alias)
- sets up an agent pool of 4 max sockets with a 10s keep alive timeout
- better error handling and re-initialization

lib/agent.js

@@ -1,6 +1,7 @@
 // Packages
 const {parse} = require('url')
-const http2 = require('spdy')
+const http = require('http')
+const https = require('https')
 const fetch = require('node-fetch')
 
 /**
@@ -18,8 +19,6 @@ module.exports = class Agent {
   constructor(url, {tls = true, debug} = {}) {
     this._url = url
     const parsed = parse(url)
-    this._host = parsed.hostname
-    this._port = parsed.port
     this._protocol = parsed.protocol
     this._debug = debug
     if (tls) {
@@ -28,30 +27,28 @@ module.exports = class Agent {
   }
 
   _initAgent() {
-    if (this._protocol !== 'https:') {
-      return
-    }
-
-    this._agent = http2.createAgent({
-      host: this._host,
-      port: this._port || 443
-    }).once('error', err => this._onError(err))
+    const module = this._protocol === 'https:' ? https : http
+    const agent = this._agent = new module.Agent({
+      keepAlive: true,
+      keepAliveMsecs: 10000,
+      maxSockets: 8
+    }).on('error', err => this._onError(err, agent))
   }
 
-  _onError(err) {
+  _onError(err, agent) {
     if (this._debug) {
       console.log('> [debug] agent connection error', err.stack)
     }
-    this._error = err
+    if (this._agent === agent) {
+      this._agent = null
+    }
   }
 
   fetch(path, opts = {}) {
-    if (this._error) {
+    if (!this._agent) {
       if (this._debug) {
-        console.log('> [debug] re-initializing agent after error')
+        console.log('> [debug] re-initializing agent')
       }
-
-      this._error = null
       this._initAgent()
     }
 
@@ -78,7 +75,7 @@ module.exports = class Agent {
     }
 
     if (this._agent) {
-      this._agent.close()
+      this._agent.destroy()
     }
   }
 }

lib/alias.js

@@ -230,13 +230,6 @@ module.exports = class Alias extends Now {
       console.log(`> Verification ${chalk.bold('OK')}!`)
     }
 
-    // unfortunately there's a situation where the verification
-    // ownership code path in the `catch` above makes the
-    // agent unexpectedly close. this is a workaround until
-    // we figure out what's going on with `node-spdy`
-    this._agent.close()
-    this._agent._initAgent()
-
     const newAlias = await this.createAlias(depl, alias)
     if (!newAlias) {
       throw new Error(`Unexpected error occurred while setting up alias: ${JSON.stringify(newAlias)}`)