feat: add contentType option

README.md

@@ -54,6 +54,14 @@ of the `Range` request header.
 Enable or disable setting `Cache-Control` response header, defaults to
 true. Disabling this will ignore the `immutable` and `maxAge` options.
 
+##### contentType
+
+By default, this library uses the `mime` module to set the `Content-Type`
+of the response based on the file extension of the requested file.
+
+To disable this functionality, set `contentType` to `false`.
+The `Content-Type` header will need to be set manually if disabled.
+
 ##### dotfiles
 
 Set how "dotfiles" are treated when encountered. A dotfile is a file

lib/send.js

@@ -101,6 +101,10 @@ function normalizeOptions (options) {
     ? Boolean(options.cacheControl)
     : true
 
+  const contentType = options.contentType !== undefined
+    ? Boolean(options.contentType)
+    : true
+
   const etag = options.etag !== undefined
     ? Boolean(options.etag)
     : true
@@ -137,6 +141,7 @@ function normalizeOptions (options) {
   return {
     acceptRanges,
     cacheControl,
+    contentType,
     etag,
     dotfiles,
     extensions,
@@ -489,13 +494,15 @@ function sendFileDirectly (request, path, stat, options) {
   }
 
   // set content-type
-  let type = mime.getType(path) || mime.default_type
-  debug('content-type %s', type)
-  if (type && isUtf8MimeType(type)) {
-    type += '; charset=utf-8'
-  }
-  if (type) {
-    headers['Content-Type'] = type
+  if (options.contentType) {
+    let type = mime.getType(path) || mime.default_type
+    debug('content-type %s', type)
+    if (type && isUtf8MimeType(type)) {
+      type += '; charset=utf-8'
+    }
+    if (type) {
+      headers['Content-Type'] = type
+    }
   }
 
   // conditional GET support

test/send.1.test.js

@@ -13,7 +13,7 @@ const { shouldNotHaveHeader, createServer } = require('./utils')
 const fixtures = path.join(__dirname, 'fixtures')
 
 test('send(file, options)', function (t) {
-  t.plan(10)
+  t.plan(11)
 
   t.test('acceptRanges', function (t) {
     t.plan(2)
@@ -60,6 +60,19 @@ test('send(file, options)', function (t) {
     })
   })
 
+  t.test('contentType', function (t) {
+    t.plan(1)
+
+    t.test('should support disabling content-type', function (t) {
+      t.plan(2)
+
+      request(createServer({ contentType: false, root: fixtures }))
+        .get('/name.txt')
+        .expect(shouldNotHaveHeader('Content-Type', t))
+        .expect(200, err => t.error(err))
+    })
+  })
+
   t.test('etag', function (t) {
     t.plan(1)
 

types/index.d.ts

@@ -44,6 +44,11 @@ declare namespace send {
      */
     cacheControl?: boolean | undefined;
 
+    /**
+     * Enable or disable setting Content-Type response header, defaults to true.
+     */
+    contentType?: boolean | undefined;
+
     /**
      * Set how "dotfiles" are treated when encountered.
      * A dotfile is a file or directory that begins with a dot (".").

types/index.test-d.ts

@@ -26,14 +26,22 @@ const req: any = {}
 }
 
 {
-  const result = await send(req, '/test.html', { maxAge: 0, root: __dirname + '/wwwroot' })
+  const result = await send(req, '/test.html', { contentType: true, maxAge: 0, root: __dirname + '/wwwroot' })
 
   expectType<SendResult>(result)
   expectType<number>(result.statusCode)
   expectType<Record<string, string>>(result.headers)
   expectType<Readable>(result.stream)
 }
 
+{
+  const result = await send(req, '/test.html', { contentType: false, root: __dirname + '/wwwroot' })
+
+  expectType<SendResult>(result)
+  expectType<number>(result.statusCode)
+  expectType<Record<string, string>>(result.headers)
+  expectType<Readable>(result.stream)
+}
 
 const result = await send(req, '/test.html')
 switch (result.type) {