Support Firebase / GCP cloud functions

[ThomasKientz]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

Support serverless firebase and GCP

Motivation

Currently we can't use this plugin with serverless GCP (or Firebase).

As explained here fastify/fastify#946 (comment) and in the doc for firebase, we need to use req.rawBody in order to parse files from multipart.

Example

No response

[reyhankaplan]

I needed this plugin and got it working with the patch below, but it might have some issues as I haven't fully tested it yet. However, it could be a starting point for a PR.

diff --git a/node_modules/@fastify/multipart/index.js b/node_modules/@fastify/multipart/index.js
index 4e2d1b3..8c7bc75 100644
--- a/node_modules/@fastify/multipart/index.js
+++ b/node_modules/@fastify/multipart/index.js
@@ -27,7 +27,8 @@ const InvalidJSONFieldError = createError('FST_INVALID_JSON_FIELD_ERROR', 'a req
 const FileBufferNotFoundError = createError('FST_FILE_BUFFER_NOT_FOUND', 'the file buffer was not found', 500)
 const NoFormData = createError('FST_NO_FORM_DATA', 'FormData is not available', 500)
 
-function setMultipart (req, _payload, done) {
+function setMultipart (req, payload, done) {
+  req.rawBody = payload.rawBody
   req[kMultipart] = true
   done()
 }
@@ -297,7 +298,15 @@ function fastifyMultipart (fastify, options, done) {
       process.nextTick(() => cleanup(err))
     })
 
-    request.pipe(bb)
+    if (request.rawBody) {
+      const stream = Readable.from(request.rawBody)
+      stream.pipe(bb)
+    } else {
+      request.pipe(bb)
+    }
 
     function onField (name, fieldValue, fieldnameTruncated, valueTruncated, encoding, contentType) {
       // don't overwrite prototypes

[Uzlopak]

GCF is a glorified express requesthandler with enabled bodyparser. module for json

So if you sent a payload with content type application/json the request.body is an object as the json payload is parsed by gcf. In GCF request.rawBody is afaik always set in POST, PUT, PATCH methods and is the payload as Buffer..

So if your modified setMultipart is only called if the content-type matches, than it could be fine. I wonder if we really need to take the Buffer to pipe it to Busboy, but I guess it is what it is. Maybe it makes sense to make a new plugin option pipeRequest (<< bad name, transformRequest?), which is by default

function pipeRequest(request, bb) {
   request.pipe(bb)
}

And you can change it in case of gcf to

function pipeRequest(request, bb) {
  Readable.from(request.rawBody).pipe(bb)
}

Then if you have other cloud platforms or whatever. you only need to modify that option and dont need any special cases here and there.

[reyhankaplan]

transformRequest would be great. Also, thanks for your detailed answer!