Adding option to select between two behaviour when file over fileSize

Author: ShakMR

.gitignore

@@ -6,6 +6,7 @@ ehthumbs.db
 Desktop.ini
 .directory
 *~
+.idea
 npm-debug.log
 node_modules
 *.log

README.md

@@ -40,6 +40,7 @@ The **req.files.foo** object will contain the following:
 * `req.files.foo.mv`: A function to move the file elsewhere on your server
 * `req.files.foo.mimetype`: The mimetype of your file
 * `req.files.foo.data`: A buffer representation of your file
+* `req.files.foo.truncated`: A boolean that represents if the file is over the size limit
 
 ### Full Example
 **Your node.js code:**
@@ -120,6 +121,7 @@ Option | Acceptable Values | Details
 --- | --- | ---
 safeFileNames | <ul><li><code>false</code>&nbsp;**(default)**</li><li><code>true</code></li><li>regex</li></ul> | Strips characters from the upload's filename. You can use custom regex to determine what to strip. If set to `true`, non-alphanumeric characters _except_ dashes and underscores will be stripped. This option is off by default.<br /><br />**Example #1 (strip slashes from file names):** `app.use(fileUpload({ safeFileNames: /\\/g }))`<br />**Example #2:** `app.use(fileUpload({ safeFileNames: true }))`
 preserveExtension | <ul><li><code>false</code>&nbsp;**(default)**</li><li><code>true</code></li><li><code>*Number*</code></li></ul> | Preserves filename extension when using <code>safeFileNames</code> option. If set to <code>true</code>, will default to an extension length of 3. If set to <code>*Number*</code>, this will be the max allowable extension length. If an extension is smaller than the extension length, it remains untouched. If the extension is longer, it is shifted.<br /><br />**Example #1 (true):**<br /><code>app.use(fileUpload({ safeFileNames: true, preserveExtension: true }));</code><br />*myFileName.ext* --> *myFileName.ext*<br /><br />**Example #2 (max extension length 2, extension shifted):**<br /><code>app.use(fileUpload({ safeFileNames: true, preserveExtension: 2 }));</code><br />*myFileName.ext* --> *myFileNamee.xt*
+abortOnLimit | <ul><li><code>false</code>&nbsp;**(default)**</li><li><code>true</code></ul> | Returns a HTTP 413 when the file is bigger than the size limit if true. Otherwise, it will add a <code>truncate = true</code> to the resulting file structure.
 
 # Help Wanted
 Pull Requests are welcomed!

lib/index.js

@@ -74,8 +74,10 @@ function processMultipart(options, req, res, next) {
     let safeFileNameRegex = /[^\w-]/g;
 
     file.on('limit', () => {
-      res.writeHead(413, {'Connection': 'close'});
-      res.end('File size limit has been reached');
+      if (options.abortOnLimit) {
+        res.writeHead(413, {'Connection': 'close'});
+        res.end('File size limit has been reached');
+      }
     });
 
     file.on('data', function(data) {
@@ -138,6 +140,7 @@ function processMultipart(options, req, res, next) {
         name: filename,
         data: buf,
         encoding: encoding,
+        truncated: file.truncated,
         mimetype: mime,
         mv: function(path, callback) {
           // Callback is passed in, use the callback API
@@ -161,8 +164,8 @@ function processMultipart(options, req, res, next) {
           /**
            * Local function that moves the file to a different location on the filesystem
            * Takes two function arguments to make it compatible w/ Promise or Callback APIs
-           * @param {Function} successFunc 
-           * @param {Function} errorFunc 
+           * @param {Function} successFunc
+           * @param {Function} errorFunc
            */
           function doMove(successFunc, errorFunc) {
             const fstream = fs.createWriteStream(path);

test/fileLimitUploads.spec.js

@@ -2,35 +2,65 @@
 
 const path = require('path');
 const request = require('supertest');
+const assert = require('assert');
 const server = require('./server');
-const app = server.setup({
-  limits: {fileSize: 200 * 1024} // set 200kb upload limit
-});
 const clearUploadsDir = server.clearUploadsDir;
 const fileDir = server.fileDir;
 
 describe('Test Single File Upload With File Size Limit', function() {
-  it(`upload 'basketball.png' (~154kb) with 200kb size limit`, function(done) {
-    let filePath = path.join(fileDir, 'basketball.png');
+  let app;
 
+  beforeEach(function() {
     clearUploadsDir();
+  });
+
+  describe('abort connection on limit reached', function() {
+    before(function() {
+      app = server.setup({
+        limits: {fileSize: 200 * 1024}, // set 200kb upload limit
+        abortOnLimit: true
+      });
+    });
+
+    it(`upload 'basketball.png' (~154kb) with 200kb size limit`, function(done) {
+      let filePath = path.join(fileDir, 'basketball.png');
 
-    request(app)
-      .post('/upload/single')
-      .attach('testFile', filePath)
-      .expect(200)
-      .end(done);
+      request(app)
+        .post('/upload/single/truncated')
+        .attach('testFile', filePath)
+        .expect(200)
+        .end(done);
+    });
+
+    it(`fail when uploading 'car.png' (~269kb) with 200kb size limit`, function(done) {
+      let filePath = path.join(fileDir, 'car.png');
+
+      request(app)
+        .post('/upload/single/truncated')
+        .attach('testFile', filePath)
+        .expect(413)
+        .end(done);
+    });
   });
 
-  it(`fail when uploading 'car.png' (~269kb) with 200kb size limit`, function(done) {
-    let filePath = path.join(fileDir, 'car.png');
+  describe('pass truncated file to the next handler', function() {
+    before(function() {
+      app = server.setup({
+        limits: {fileSize: 200 * 1024} // set 200kb upload limit
+      });
+    });
 
-    clearUploadsDir();
+    it(`fail when uploading 'car.png' (~269kb) with 200kb size limit`, function(done) {
+      let filePath = path.join(fileDir, 'car.png');
 
-    request(app)
-      .post('/upload/single')
-      .attach('testFile', filePath)
-      .expect(413)
-      .end(done);
+      request(app)
+        .post('/upload/single/truncated')
+        .attach('testFile', filePath)
+        .expect(400)
+        .end(function(err, res) {
+          assert.ok(res.error.text === 'File too big');
+          done();
+        });
+    });
   });
 });

test/server.js

@@ -92,6 +92,19 @@ const setup = function(fileUploadOptions) {
     });
   });
 
+  app.all('/upload/single/truncated', function(req, res) {
+    if (!req.files) {
+      return res.status(400).send('No files were uploaded.');
+    }
+
+    if (req.files.testFile.truncated) {
+      // status 400 to differentiate from ending the request in the on limit
+      return res.status(400).send(`File too big`);
+    }
+
+    return res.status(200).send('Upload succeed');
+  });
+
   app.all('/upload/multiple', function(req, res) {
     if (!req.files) {
       return res.status(400).send('No files were uploaded.');