feat: expose busboy defCharset, highWaterMark and fileHwm options

README.md

@@ -129,6 +129,9 @@ Key | Description
 `limits` | Limits of the uploaded data
 `preservePath` | Keep the full client-supplied path in `file.originalname` instead of just the base name
 `defParamCharset` | Default character set to use for values of part header parameters (e.g. filename) that are not extended parameters (that contain an explicit charset). Default: `'latin1'`
+`defCharset` | Default character set to use for text field values that do not declare one. Default: `'utf8'`
+`highWaterMark` | `highWaterMark` of the multipart parser stream. Default: busboy's default
+`fileHwm` | `highWaterMark` of each file stream (`file.stream`). Default: busboy's default
 
 In an average web app, only `dest` might be required, and configured as shown in
 the following example.

index.js

@@ -20,6 +20,9 @@ function Multer (options) {
   this.limits = options.limits
   this.preservePath = options.preservePath
   this.defParamCharset = options.defParamCharset || 'latin1'
+  this.defCharset = options.defCharset
+  this.highWaterMark = options.highWaterMark
+  this.fileHwm = options.fileHwm
   this.fileFilter = options.fileFilter || allowAll
 }
 
@@ -49,6 +52,9 @@ Multer.prototype._makeMiddleware = function (fields, fileStrategy) {
       limits: this.limits,
       preservePath: this.preservePath,
       defParamCharset: this.defParamCharset,
+      defCharset: this.defCharset,
+      highWaterMark: this.highWaterMark,
+      fileHwm: this.fileHwm,
       storage: this.storage,
       fileFilter: wrappedFileFilter,
       fileStrategy: fileStrategy
@@ -80,6 +86,9 @@ Multer.prototype.any = function () {
       limits: this.limits,
       preservePath: this.preservePath,
       defParamCharset: this.defParamCharset,
+      defCharset: this.defCharset,
+      highWaterMark: this.highWaterMark,
+      fileHwm: this.fileHwm,
       storage: this.storage,
       fileFilter: this.fileFilter,
       fileStrategy: 'ARRAY'

lib/make-middleware.js

@@ -89,6 +89,9 @@ function makeMiddleware (setup) {
     var fileStrategy = options.fileStrategy
     var preservePath = options.preservePath
     var defParamCharset = options.defParamCharset
+    var defCharset = options.defCharset
+    var highWaterMark = options.highWaterMark
+    var fileHwm = options.fileHwm
 
     req.body = Object.create(null)
 
@@ -198,7 +201,10 @@ function makeMiddleware (setup) {
         headers: req.headers,
         limits: busboyLimits,
         preservePath: preservePath,
-        defParamCharset: defParamCharset
+        defParamCharset: defParamCharset,
+        defCharset: defCharset,
+        highWaterMark: highWaterMark,
+        fileHwm: fileHwm
       })
     } catch (err) {
       return next(err)

test/busboy-options.js

@@ -0,0 +1,131 @@
+/* eslint-env mocha */
+
+var assert = require('assert')
+var stream = require('stream')
+
+var multer = require('../')
+
+// Multipart body with one text field whose value is "åäö" encoded as latin1
+// (bytes e5 e4 f6) and no charset declared for the part.
+function latin1FieldRequest () {
+  var boundary = 'AaB03x'
+  var body = Buffer.concat([
+    Buffer.from('--' + boundary + '\r\nContent-Disposition: form-data; name="name"\r\n\r\n'),
+    Buffer.from([0xe5, 0xe4, 0xf6]),
+    Buffer.from('\r\n--' + boundary + '--\r\n')
+  ])
+  var req = new stream.PassThrough()
+
+  req.headers = {
+    'content-type': 'multipart/form-data; boundary=' + boundary,
+    'content-length': body.length
+  }
+  req.end(body)
+
+  return req
+}
+
+function fileRequest () {
+  var boundary = 'AaB03x'
+  var body = [
+    '--' + boundary,
+    'Content-Disposition: form-data; name="file"; filename="a.txt"',
+    'Content-Type: text/plain',
+    '',
+    'file content',
+    '--' + boundary + '--',
+    ''
+  ].join('\r\n')
+  var req = new stream.PassThrough()
+
+  req.headers = {
+    'content-type': 'multipart/form-data; boundary=' + boundary,
+    'content-length': body.length
+  }
+  req.end(body)
+
+  return req
+}
+
+// Storage engine that records the file stream's highWaterMark.
+function recordingStorage (record) {
+  return {
+    _handleFile: function (req, file, cb) {
+      record.readableHighWaterMark = file.stream.readableHighWaterMark
+      file.stream.resume()
+      file.stream.on('end', function () { cb(null, {}) })
+    },
+    _removeFile: function (req, file, cb) { cb(null) }
+  }
+}
+
+describe('busboy options', function () {
+  it('should decode text fields as utf8 by default', function (done) {
+    var upload = multer()
+    var req = latin1FieldRequest()
+
+    upload.none()(req, null, function (err) {
+      assert.ifError(err)
+      // latin1 bytes are not valid utf8, so the value is decoded with replacement characters
+      assert.notStrictEqual(req.body.name, 'åäö')
+      assert.ok(req.body.name.indexOf('\ufffd') !== -1)
+      done()
+    })
+  })
+
+  it('should decode text fields with the given defCharset', function (done) {
+    var upload = multer({ defCharset: 'latin1' })
+    var req = latin1FieldRequest()
+
+    upload.none()(req, null, function (err) {
+      assert.ifError(err)
+      assert.strictEqual(req.body.name, 'åäö')
+      done()
+    })
+  })
+
+  it('should apply defCharset to .any() as well', function (done) {
+    var upload = multer({ defCharset: 'latin1' })
+    var req = latin1FieldRequest()
+
+    upload.any()(req, null, function (err) {
+      assert.ifError(err)
+      assert.strictEqual(req.body.name, 'åäö')
+      done()
+    })
+  })
+
+  it('should keep the default file stream highWaterMark when fileHwm is not set', function (done) {
+    var record = {}
+    var upload = multer({ storage: recordingStorage(record) })
+
+    upload.single('file')(fileRequest(), null, function (err) {
+      assert.ifError(err)
+      assert.strictEqual(record.readableHighWaterMark, new stream.Readable().readableHighWaterMark)
+      done()
+    })
+  })
+
+  it('should pass fileHwm to the file streams', function (done) {
+    var record = {}
+    var upload = multer({ storage: recordingStorage(record), fileHwm: 1024 })
+
+    upload.single('file')(fileRequest(), null, function (err) {
+      assert.ifError(err)
+      assert.strictEqual(record.readableHighWaterMark, 1024)
+      done()
+    })
+  })
+
+  it('should accept highWaterMark for the parser stream', function (done) {
+    var record = {}
+    var upload = multer({ storage: recordingStorage(record), highWaterMark: 1024 })
+    var req = fileRequest()
+
+    upload.single('file')(req, null, function (err) {
+      assert.ifError(err)
+      assert.strictEqual(req.file.originalname, 'a.txt')
+      done()
+    })
+  })
+})