From f420e045be827fad6345f0f190d687938f47c959 Mon Sep 17 00:00:00 2001
From: Misha Wolfson <misha@ginkgobioworks.com>
Date: Thu, 15 Dec 2016 17:55:59 -0500
Subject: [PATCH] Refactor setting resolution from command line and config file

---
 lib/spserver.js | 97 +++++++++++++++++++++++++++++++++----------------
 1 file changed, 65 insertions(+), 32 deletions(-)

diff --git a/lib/spserver.js b/lib/spserver.js
index b7cb21c..b9f7e55 100644
--- a/lib/spserver.js
+++ b/lib/spserver.js
@@ -10,9 +10,15 @@ var nStatic = require('node-static');
 var config = require('./config');
 var logger = require('./logger');
 
-var env = config.get('NODE_ENV');
 
-var spserver = function (settings) {
+// The different config sources sometimes manipulate different setting names.
+// E.g. command line flags maniuplate root settings, but config files can
+// manipulate settings at the prod/debug level. Resolve all of these into a
+// final object of settings.
+function _resolveFinalSettings(settings) {
+  var finalSettings = {};
+  var env = config.get('NODE_ENV');
+
   if (!settings) {
     settings = config.get();
   }
@@ -20,9 +26,55 @@ var spserver = function (settings) {
     settings[env] = {};
   }
 
-  var fileServer = new nStatic.Server(path.resolve(settings.serve || settings[env].server));
+  // For 'name', 'file', 'serve', and 'port', default to the global setting rather than an
+  // individual environment's setting, because it might have been set via command-line flags
+  _(['name', 'file', 'serve', 'port']).forEach(function (field) {
+    finalSettings[field] = settings[field] || settings[env][field];
+  });
 
-  var base = generateBase(path.resolve(settings.file || settings[env].file), settings);
+  // For 'staticOptions', there are no command-line flags, so individual configuration options
+  // override global defaults where set
+  finalSettings.staticOptions = _.defaultsDeep(settings.staticOptions, settings[env].staticOptions);
+
+  // Make a template function so we can just pass that in downstream
+  finalSettings.template = (settings.template || settings[env].template) ?
+    function (contents) {
+      // Note: template is run with _original_, non-resolved settings
+      return _.template(contents)(settings);
+    } : null;
+
+  return finalSettings;
+}
+
+function generateBase(file, finalSettings) {
+  if (!file) {
+    return null;
+  }
+
+  if (_.endsWith(file, 'js')) {
+    return require(file);
+  }
+
+  var contents = fs.readFileSync(file);
+  if (finalSettings.template) {
+    contents = finalSettings.template(contents);
+  }
+
+  return function(req, res) {
+    res.writeHead(200, {'Content-Type': 'text/html'});
+    res.end(contents);
+  };
+}
+
+var spserver = function (settings) {
+  var finalSettings = _resolveFinalSettings(settings);
+
+  var fileServer = new nStatic.Server(
+    path.resolve(finalSettings.serve),
+    finalSettings.staticOptions
+  );
+
+  var base = generateBase(path.resolve(finalSettings.file), finalSettings);
 
   var server = http.createServer(function (req, res) {
     logger.debug('[REQ] GET:', req.url);
@@ -52,37 +104,18 @@ var spserver = function (settings) {
     }).resume();
   });
 
-  server.listen(settings.port || settings[env].port);
+  server.listen(finalSettings.port);
 
-  logger.info('Static server',
-              settings.name,
-              'is listening on port',
-              settings.port || settings[env].port,
-              'with public folder',
-              settings.serve || settings[env].serve);
+  logger.info(
+    'Started single-page server: ' + finalSettings.name +
+    ', base file: ' + finalSettings.file +
+    ', static folder: ' + finalSettings.serve +
+    ', port: ' + finalSettings.port
+  );
+
+  return server;
 };
 
 spserver.generateBase = generateBase;
 
-function generateBase(file, settings) {
-  if (!file) {
-    return null;
-  }
-
-  if (_.endsWith(file, 'js')) {
-    return require(file);
-  }
-
-  var contents = fs.readFileSync(file);
-
-  if (settings.template || settings[env] && settings[env].template) {
-    contents = _.template(contents)(settings);
-  }
-
-  return function(req, res) {
-    res.writeHead(200, {'Content-Type': 'text/html'});
-    res.end(contents);
-  };
-}
-
 module.exports = spserver;