added some multipart tests

package.json

@@ -35,6 +35,7 @@
     "performance": "npm run lint && node performanceTest/test"
   },
   "devDependencies": {
+    "@fastify/multipart": "7.2.0",
     "@types/aws-lambda": "8.10.106",
     "aws-lambda": "^1.0.7",
     "aws-serverless-express": "^3.4.0",

test/multipart.test.js

@@ -0,0 +1,106 @@
+const { test } = require('tap')
+const fastify = require('fastify')
+const awsLambdaFastify = require('../index')
+const multipart = require('@fastify/multipart')
+
+test('should parse the multipart form-data successfully given raw multipart form data', async (t) => {
+  t.plan(8)
+
+  const app = fastify()
+  const evt = {
+    version: '2.0',
+    httpMethod: 'POST',
+    path: '/test',
+    headers: {
+      'content-type': 'multipart/form-data; boundary=----WebKitFormBoundaryDP6Z1qHQSzB6Pf8c'
+    },
+    body: ['------WebKitFormBoundaryDP6Z1qHQSzB6Pf8c',
+      'Content-Disposition: form-data; name="uploadFile1"; filename="test.txt"',
+      'Content-Type: text/plain',
+      '',
+      'Hello World!',
+      '------WebKitFormBoundaryDP6Z1qHQSzB6Pf8c--'
+    ].join('\r\n'),
+    isBase64Encoded: false
+  }
+
+  app.register(multipart, { attachFieldsToBody: true })
+  app.post('/test', async (request, reply) => {
+    t.equal(request.body.uploadFile1.fieldname, 'uploadFile1')
+    t.equal(request.body.uploadFile1.filename, 'test.txt')
+    t.equal(request.body.uploadFile1.encoding, '7bit')
+    t.equal(request.body.uploadFile1.mimetype, 'text/plain')
+    t.equal(Buffer.from(request.body.uploadFile1._buf).toString('utf-8'), 'Hello World!')
+    reply.send({ hello: 'world' })
+  })
+  const proxy = awsLambdaFastify(app, { serializeLambdaArguments: true })
+  const ret = await proxy(evt)
+  t.equal(ret.statusCode, 200)
+  t.equal(ret.body, '{"hello":"world"}')
+  t.equal(ret.isBase64Encoded, false)
+})
+
+test('should parse the multipart form-data successfully given base64 encoded form data', async (t) => {
+  t.plan(8)
+
+  const app = fastify()
+  const evt = {
+    version: '2.0',
+    httpMethod: 'POST',
+    path: '/test',
+    headers: {
+      'content-type': 'multipart/form-data; boundary=----WebKitFormBoundaryDP6Z1qHQSzB6Pf8c'
+    },
+    body: `LS0tLS0tV2ViS2l0Rm9ybUJvdW5kYXJ5RFA2WjFxSFFTekI2UGY4Yw0KQ29udGVudC1EaXNwb3NpdGlvbjogZm9ybS1kYXRhOyBuYW1lPSJ1cGxvYWRGaWxlMSI7IGZpb
+      GVuYW1lPSJ0ZXN0LnR4dCINCkNvbnRlbnQtVHlwZTogdGV4dC9wbGFpbg0KDQpIZWxsbyBXb3JsZCENCi0tLS0tLVdlYktpdEZvcm1Cb3VuZGFyeURQNloxcUhRU3pCNl
+      BmOGMNCkNvbnRlbnQtRGlzcG9zaXRpb246IGZvcm0tZGF0YTsgbmFtZT0idXBsb2FkRmlsZTIiOyBmaWxlbmFtZT0iIg0KQ29udGVudC1UeXBlOiBhcHBsaWNhdGlvbi9
+      vY3RldC1zdHJlYW0NCg0KDQotLS0tLS1XZWJLaXRGb3JtQm91bmRhcnlEUDZaMXFIUVN6QjZQZjhjLS0NCg==`,
+    isBase64Encoded: true
+  }
+
+  app.register(multipart, { attachFieldsToBody: true })
+  app.post('/test', async (request, reply) => {
+    t.equal(request.body.uploadFile1.fieldname, 'uploadFile1')
+    t.equal(request.body.uploadFile1.filename, 'test.txt')
+    t.equal(request.body.uploadFile1.encoding, '7bit')
+    t.equal(request.body.uploadFile1.mimetype, 'text/plain')
+    t.equal(Buffer.from(request.body.uploadFile1._buf).toString('utf-8'), 'Hello World!')
+    reply.send({ hello: 'world' })
+  })
+  const proxy = awsLambdaFastify(app, { serializeLambdaArguments: true })
+  const ret = await proxy(evt)
+  t.equal(ret.statusCode, 200)
+  t.equal(ret.body, '{"hello":"world"}')
+  t.equal(ret.isBase64Encoded, false)
+})
+
+test('should parse the multipart form-data successfully given utf8 encoded form data', async (t) => {
+  t.plan(7)
+
+  const app = fastify()
+  const evt = {
+    version: '2.0',
+    httpMethod: 'POST',
+    path: '/test',
+    headers: {
+      'content-type': 'multipart/form-data; boundary=xYzZY'
+    },
+    body: '--xYzZY\r\nContent-Disposition: form-data; name="html"\r\n\r\n<p>Hello World</p>\r\n--xYzZY--\r\n',
+    isBase64Encoded: false
+  }
+
+  app.register(multipart, { attachFieldsToBody: true })
+  app.post('/test', async (request, reply) => {
+    console.log(request.body)
+    t.equal(request.body.html.fieldname, 'html')
+    t.equal(request.body.html.encoding, '7bit')
+    t.equal(request.body.html.mimetype, 'text/plain')
+    t.equal(request.body.html.value, '<p>Hello World</p>')
+    reply.send({ hello: 'world' })
+  })
+  const proxy = awsLambdaFastify(app, { serializeLambdaArguments: true })
+  const ret = await proxy(evt)
+  t.equal(ret.statusCode, 200)
+  t.equal(ret.body, '{"hello":"world"}')
+  t.equal(ret.isBase64Encoded, false)
+})