feat(file): add option to define custom tmp file names

Now one can define `tmpFileName` function inside the config, which can return the file name to be
used for tmp files

Enhances #2

examples/config.js

@@ -134,5 +134,24 @@ module.exports = {
     |
     */
     processManually: []
+
+    /*
+    |--------------------------------------------------------------------------
+    | Temporary file name
+    |--------------------------------------------------------------------------
+    |
+    | Define a function, which should return a string to be used as the
+    | tmp file name.
+    |
+    | If not defined, Bodyparser will use `uuid` as the tmp file name.
+    |
+    | To be defined as. If you are defining the function, then do make sure
+    | to return a value from it.
+    |
+    | tmpFileName () {
+    |   return 'some-unique-value'
+    | }
+    |
+    */
   }
 }

src/BodyParser/index.js

@@ -250,7 +250,7 @@ class BodyParser {
 
       request.multipart.file('*', {}, async (file) => {
         this.files.add(file._fieldName, file)
-        await file.moveToTmp()
+        await file.moveToTmp(this.config.files.tmpFileName)
       })
 
       request.multipart.field((name, value) => {

src/Multipart/File.js

@@ -328,14 +328,22 @@ class File {
    *
    * @method moveToTmp
    *
+   * @package {Function} tmpNameFn
+   *
    * @return {Promise}
    */
-  moveToTmp () {
+  moveToTmp (tmpNameFn) {
     if (this.ended) {
       throw CE.FileMoveException.multipleMoveAttempts(this._fieldName)
     }
 
-    this._tmpPath = path.join(os.tmpdir(), `ab-${uuid()}.tmp`)
+    /**
+     * The function to be used for generating
+     * the tmp file name
+     */
+    tmpNameFn = typeof (tmpNameFn) === 'function' ? tmpNameFn : () => `ab-${uuid()}.tmp`
+
+    this._tmpPath = path.join(os.tmpdir(), tmpNameFn())
     debug('moving file %s to tmp directory %s', this._fieldName, this._tmpPath)
     return this._streamFile(this._tmpPath)
   }

test/unit/body-parser.spec.js

@@ -11,12 +11,13 @@
 
 const test = require('japa')
 const path = require('path')
+const os = require('os')
 const Browser = require('zombie')
 const { Config } = require('@adonisjs/sink')
 const app = require('./app')
 const BodyParser = require('../../src/BodyParser')
-const supertest = require('supertest')
 const TEST_URL = 'http://localhost:4000/'
+const supertest = require('supertest')
 
 test.group('Body Parser', (group) => {
   group.before(() => {
@@ -511,4 +512,28 @@ test.group('Body Parser', (group) => {
     assert.deepEqual(body.files, {})
     assert.deepEqual(body.raw, {})
   })
+
+  test('create custom tmp file name from config', async (assert) => {
+    /**
+     * Post method to handle the form submission
+     */
+    app.post = async function (request, res) {
+      const config = new Config()
+      config.set('bodyParser.files.tmpFileName', function () {
+        return 'abc'
+      })
+
+      const parser = new BodyParser(config)
+      await parser.handle({ request }, function () {})
+      res.writeHead(200, { 'content-type': 'application/json' })
+      res.write(JSON.stringify(request._files['ignore-file'].toJSON()))
+      res.end()
+    }
+
+    const { body } = await supertest(app.server)
+      .post('/')
+      .attach('ignore-file', path.join(__dirname, '../../.gitignore'))
+
+    assert.equal(body.tmpPath, path.join(os.tmpdir(), 'abc'))
+  })
 })