refactor: Extract createHttpServer Function and Replace Temp with Query

Signed-off-by: BoHong Li <a60814billy@gmail.com>

app.js

@@ -26,30 +26,33 @@ var response = require('./lib/response')
 var models = require('./lib/models')
 var csp = require('./lib/csp')
 
+function createHttpServer () {
+  if (config.useSSL) {
+    const ca = (function () {
+      let i, len, results
+      results = []
+      for (i = 0, len = config.sslCAPath.length; i < len; i++) {
+        results.push(fs.readFileSync(config.sslCAPath[i], 'utf8'))
+      }
+      return results
+    })()
+    const options = {
+      key: fs.readFileSync(config.sslKeyPath, 'utf8'),
+      cert: fs.readFileSync(config.sslCertPath, 'utf8'),
+      ca: ca,
+      dhparam: fs.readFileSync(config.dhParamPath, 'utf8'),
+      requestCert: false,
+      rejectUnauthorized: false
+    }
+    return require('https').createServer(options, app)
+  } else {
+    return require('http').createServer(app)
+  }
+}
+
 // server setup
 var app = express()
-var server = null
+var server = createHttpServer()
-if (config.useSSL) {
-  var ca = (function () {
-    var i, len, results
-    results = []
-    for (i = 0, len = config.sslCAPath.length; i < len; i++) {
-      results.push(fs.readFileSync(config.sslCAPath[i], 'utf8'))
-    }
-    return results
-  })()
-  var options = {
-    key: fs.readFileSync(config.sslKeyPath, 'utf8'),
-    cert: fs.readFileSync(config.sslCertPath, 'utf8'),
-    ca: ca,
-    dhparam: fs.readFileSync(config.dhParamPath, 'utf8'),
-    requestCert: false,
-    rejectUnauthorized: false
-  }
-  server = require('https').createServer(options, app)
-} else {
-  server = require('http').createServer(app)
-}
 
 // logger
 app.use(morgan('combined', {