minor cleanup

Author: nemtsov

README.md

@@ -10,8 +10,8 @@ If you've used the Google APIs, provided a `?fields=` query-string to get a
 and wanted to do the same for your own server, now you can do so with this
 middleware.
 
-*Underneath, this middleware uses [json-mask](https://github.com/nemtsov/json-mask).
-Use it directly without this middleware if you need more flexibility.*
+_Underneath, this middleware uses [json-mask](https://github.com/nemtsov/json-mask).
+Use it directly without this middleware if you need more flexibility._
 
 # Installation
 
@@ -22,26 +22,29 @@ npm install express-partial-response
 # Usage
 
 ```js
-const express = require('express')
-const partialResponse = require('express-partial-response')
-const app = express()
+const express = require('express');
+const partialResponse = require('express-partial-response');
+const app = express();
 
-app.use(partialResponse())
+app.use(partialResponse());
 
-app.get('/', function (req, res, next) {
+app.get('/', (req, res) => {
   res.json({
-    firstName: 'Mohandas'
-    , lastName: 'Gandhi'
-    , aliases: [{
-      firstName: 'Mahatma'
-      , lastName: 'Gandhi'
-    }, {
-      firstName: 'Bapu'
-    }]
-  })
-})
-
-app.listen(4000)
+    firstName: 'Mohandas',
+    lastName: 'Gandhi',
+    aliases: [
+      {
+        firstName: 'Mahatma',
+        lastName: 'Gandhi'
+      },
+      {
+        firstName: 'Bapu'
+      }
+    ]
+  });
+});
+
+app.listen(4000);
 ```
 
 Let's test it:
@@ -70,9 +73,11 @@ Look at [json-mask](https://github.com/nemtsov/json-mask) for the available synt
 `query` specifies the query-string to use. Defaults to `fields`
 
 ```js
-app.use(partialResponse({
-  query: 'filter'
-}))
+app.use(
+  partialResponse({
+    query: 'filter'
+  })
+);
 ```
 
 # License

example/package.json

@@ -1,7 +1,6 @@
 {
   "name": "example",
   "version": "1.0.0",
-  "description": "",
   "main": "server.js",
   "scripts": {
     "start": "node server.js"

example/server.js

@@ -4,7 +4,7 @@ const app = express();
 
 app.use(partialResponse());
 
-app.get('/', function(req, res, next) {
+app.get('/', (req, res) => {
   res.json({
     firstName: 'Mohandas',
     lastName: 'Gandhi',
@@ -20,7 +20,7 @@ app.get('/', function(req, res, next) {
   });
 });
 
-app.listen(4000, function() {
+app.listen(4000, () => {
   const prefix = "curl 'http://localhost:4000?fields=%s'";
   console.log('Server running on :4000, try the following:');
   console.log(prefix, '*');

index.js

@@ -1,38 +1,34 @@
 const jsonMask = require('json-mask');
 
-const badCode = code => code >= 300 || code < 200;
+function isBadCode(statusCode) {
+  return statusCode < 200 || statusCode >= 300;
+}
 
-module.exports = function(opt) {
-  opt = opt || {};
+module.exports = function(options = {}) {
+  options = { query: 'fields', ...options };
 
-  function partialResponse(obj, fields) {
-    if (!fields) return obj;
-    return jsonMask(obj, fields);
-  }
-
-  function wrap(orig) {
+  function wrap(resJson) {
     return function(obj) {
-      const param = this.req.query[opt.query || 'fields'];
-      if (1 === arguments.length) {
-        if (badCode(this.statusCode)) {
-          return orig(this.statusCode, arguments[0]);
-        } else {
-          return orig(partialResponse(obj, param));
+      const fields = this.req.query[options.query];
+
+      // deprecated API that are still supported in v4
+      if (arguments.length > 1) {
+        // res.json(obj, status)
+        if ('number' === typeof arguments[1] && !isBadCode(arguments[1])) {
+          return resJson(jsonMask(obj, fields), arguments[1]);
         }
-      }
 
-      if ('number' === typeof arguments[1] && !badCode(arguments[1])) {
-        // res.json(body, status) backwards compat
-        return orig(partialResponse(obj, param), arguments[1]);
-      }
+        // res.json(status, obj)
+        if ('number' === typeof obj && !isBadCode(obj)) {
+          return resJson(obj, jsonMask(arguments[1], fields));
+        }
 
-      if ('number' === typeof obj && !badCode(obj)) {
-        // res.json(status, body) backwards compat
-        return orig(obj, partialResponse(arguments[1], param));
+        return resJson(...arguments);
       }
 
-      // The original actually returns this.send(body)
-      return orig(obj, arguments[1]);
+      return isBadCode(this.statusCode)
+        ? resJson(...arguments)
+        : resJson(jsonMask(obj, fields));
     };
   }