lowercase all headers, then normalize on the way out

package.json

@@ -30,6 +30,7 @@
   "dependencies": {
     "accepts": "^1.3.3",
     "cookie": "^0.3.1",
+    "header-case-normalizer": "^1.0.3",
     "lodash.clonedeep": "^4.5.0",
     "lodash.get": "^4.4.2",
     "lodash.has": "^4.5.2",

src/events/response.js

@@ -1,7 +1,9 @@
 'use strict'
 const _toString = require('lodash.tostring')
+const _transform = require('lodash.transform')
 const cookie = require('cookie')
 const mime = require('mime')
+const normalizeHeader = require('header-case-normalizer')
 
 const corsHeader = {
   'Access-Control-Allow-Origin': '*',
@@ -42,18 +44,11 @@ class Response {
     this.body = ''
 
     /**
-     * Map of headers to include with the request
+     * Map of lowercase headers to include with the request
      * @type {{}}
      */
     this.headers = {}
 
-    /**
-     * Map of headers with lowercase keys
-     * @type {{}}
-     * @private
-     */
-    this._headers = {}
-
     if (typeof opts.headers === 'object') {
       for (const key in opts.headers) {
         this.set(key, opts.headers[key])
@@ -124,7 +119,9 @@ class Response {
 
     const res = {
       statusCode: this.statusCode,
-      headers: this.headers,
+      headers: _transform(this.headers, (result, val, key) => {
+        result[normalizeHeader(key)] = val
+      }),
       body: body,
     }
 
@@ -199,7 +196,7 @@ class Response {
    * @public
    */
   get (field) {
-    return this._headers[field.toLowerCase()]
+    return this.headers[field.toLowerCase()]
   }
 
   /**
@@ -225,8 +222,7 @@ class Response {
         ? val.map(_toString)
         : _toString(val)
 
-      this.headers[field] = value
-      this._headers[field.toLowerCase()] = value
+      this.headers[field.toLowerCase()] = value
     } else {
       for (const key in field) {
         this.set(key, field[key])

test/events/response.test.js

@@ -5,23 +5,23 @@ const Response = require('../../src/events/response')
 describe('events', () => {
   describe('Response', () => {
     describe('#set', () => {
-      it('should set key with value in headers object', () => {
+      it('should set a lowercase key with value in headers object', () => {
         const res = new Response()
         expect(res.headers).to.eql({})
         res.set('Some', 'Header')
-        expect(res.headers['Some']).to.eq('Header')
+        expect(res.headers['some']).to.eq('Header')
       })
 
       it('should force a string', () => {
         const res = new Response()
         res.set('X-Limit', 2000)
-        expect(res.headers['X-Limit']).to.eq('2000')
+        expect(res.headers['x-limit']).to.eq('2000')
       })
 
       it('should set a list of header values', () => {
         const res = new Response()
         res.set('X-Limits', [100, 200])
-        expect(res.headers['X-Limits']).to.eql(['100', '200'])
+        expect(res.headers['x-limits']).to.eql(['100', '200'])
       })
 
       it('should set a an object of headers', () => {
@@ -30,8 +30,8 @@ describe('events', () => {
           'X-Limit': 200,
           'X-Blah': 'meh',
         })
-        expect(res.headers['X-Limit']).to.eq('200')
-        expect(res.headers['X-Blah']).to.eq('meh')
+        expect(res.headers['x-limit']).to.eq('200')
+        expect(res.headers['x-blah']).to.eq('meh')
       })
 
       it('should be chainable', () => {
@@ -41,8 +41,8 @@ describe('events', () => {
         })
           .set('X-Limit', 200)
 
-        expect(res.headers['X-Limit']).to.eq('200')
-        expect(res.headers['X-Blah']).to.eq('meh')
+        expect(res.headers['x-limit']).to.eq('200')
+        expect(res.headers['x-blah']).to.eq('meh')
       })
     })
 
@@ -51,22 +51,22 @@ describe('events', () => {
         const res = new Response()
         expect(res.headers).to.eql({})
         res.append('Some', 'Header')
-        expect(res.headers['Some']).to.eq('Header')
+        expect(res.headers['some']).to.eq('Header')
       })
 
       it('should be overriden with set', () => {
         const res = new Response()
         res.append('X-Limits', [100, 200])
         res.set('X-Limits', 300)
-        expect(res.headers['X-Limits']).to.eq('300')
+        expect(res.headers['x-limits']).to.eq('300')
       })
 
       it('should be chainable', () => {
         const res = new Response()
         res.append('X-Blah', 'meh')
           .append('X-Blah', 200)
 
-        expect(res.headers['X-Blah']).to.eql(['meh', '200'])
+        expect(res.headers['x-blah']).to.eql(['meh', '200'])
       })
     })
 
@@ -82,13 +82,13 @@ describe('events', () => {
       it('should set content type with mime look up', () => {
         const res = new Response()
         res.contentType('html')
-        expect(res.headers['Content-Type']).to.eq('text/html')
+        expect(res.headers['content-type']).to.eq('text/html')
       })
 
       it('should set content string with / content type', () => {
         const res = new Response()
         res.contentType('text/plain')
-        expect(res.headers['Content-Type']).to.eq('text/plain')
+        expect(res.headers['content-type']).to.eq('text/plain')
       })
     })
 
@@ -109,33 +109,33 @@ describe('events', () => {
       it('should add cookie header', () => {
         const res = new Response()
         res.cookie('some', 'value')
-        expect(res.headers['Set-Cookie']).to.eql('some=value; Path=/')
+        expect(res.headers['set-cookie']).to.eql('some=value; Path=/')
       })
 
       it('should be chainable', () => {
         const res = new Response()
         res.cookie('some', 'value')
           .cookie('another', 'value')
 
-        expect(res.headers['Set-Cookie']).to.eql(['some=value; Path=/', 'another=value; Path=/'])
+        expect(res.headers['set-cookie']).to.eql(['some=value; Path=/', 'another=value; Path=/'])
       })
 
       it('should handle a JSON-able object', () => {
         const res = new Response()
         res.cookie('guy', { blah: 'meh' })
-        expect(res.headers['Set-Cookie']).to.eql(`guy=${encodeURIComponent('j:{"blah":"meh"}')}; Path=/`)
+        expect(res.headers['set-cookie']).to.eql(`guy=${encodeURIComponent('j:{"blah":"meh"}')}; Path=/`)
       })
 
       it('should support options', () => {
         const res = new Response()
         res.cookie('some', 'value', { secure: true, httpOnly: true })
-        expect(res.headers['Set-Cookie']).to.eql('some=value; Path=/; HttpOnly; Secure')
+        expect(res.headers['set-cookie']).to.eql('some=value; Path=/; HttpOnly; Secure')
       })
 
       it('should set max-age relative to now', () => {
         const res = new Response()
         res.cookie('some', 'value', { maxAge: 1000 })
-        expect(res.headers['Set-Cookie'][0]).not.to.contain('Thu, 01 Jan 1970 00:00:01 GMT')
+        expect(res.headers['set-cookie'][0]).not.to.contain('Thu, 01 Jan 1970 00:00:01 GMT')
       })
     })
 
@@ -149,6 +149,17 @@ describe('events', () => {
         })
       })
 
+      it('should return normalized headers', () => {
+        const res = new Response({
+          headers: { 'X-Some-Header': 'some-val' },
+        })
+        expect(res.send('blah')).to.eql({
+          statusCode: 200,
+          headers: { 'Content-Type': 'text/plain', 'X-Some-Header': 'some-val' },
+          body: 'blah',
+        })
+      })
+
       it('should not overwrite content type if set', () => {
         const res = new Response()
         res.contentType('html')
@@ -251,7 +262,7 @@ describe('events', () => {
         const res = new Response({
           headers: { 'X-Some': 'Thing' },
         })
-        expect(res.headers['X-Some']).to.eq('Thing')
+        expect(res.headers['x-some']).to.eq('Thing')
         res.set('Blah', '1')
         expect(Object.keys(res.headers)).to.have.lengthOf(2)
       })
@@ -260,7 +271,7 @@ describe('events', () => {
         const res = new Response({
           cors: true,
         })
-        expect(res.headers['Access-Control-Allow-Origin']).to.eq('*')
+        expect(res.headers['access-control-allow-origin']).to.eq('*')
       })
     })
   })