Juniper Rocket Multipart

The current crate provides with a handler that allows using multipart/data-form requests on a Rocket webserver with Juniper.

It replicates the default behavior of Juniper for requests with content-type header of application/json and application/graphql.

Disclaimer

The current crate is a still on-going process as it lacks yet :

• Unit tests
• Rebuilding the provided map objects
• Max bytes read per file is still hardcoded

Yet it should be functional. Use it at your own risks.

How to use

You can load the GraphQLUploadWrapper the same way you load the GraphQLRequest as both are data guards. The main difference will be that instead, you'll call the execution of the query through the operations property of the wrapper.

Below is basic example :

#[rocket::post("/upload", data = "<request>")]
pub async fn upload<'r>(
   request: GraphQLUploadWrapper,
   schema: &State<Schema>,
) -> GraphQLResponse {
   request.operations.execute(&*schema, &Context).await
}

Fetching the uploaded files

In order to fetch the uploaded files You'll need to implement your own context object That will pass the buffered files to your execution methods.

Example :

struct Ctx{
  files: Option<HashMap<String, TempFile>>
};
impl juniper::Context for Ctx {}

You'll then be able to inject the buffered files to your operations like this :

struct Ctx{ files: Option<HashMap<String, TempFile>> };
impl juniper::Context for Ctx {}

#[rocket::post("/upload", data = "<request>")]
pub async fn upload<'r>(
   request: GraphQLUploadWrapper,
   schema: &State<Schema>,
) -> GraphQLResponse {
  request.operations.execute(&*schema, &Ctx{ files: request.files }).await
}

Notes about processed files

The Wrapper does nothing special with the uploaded files aside allocating them in heap memory through the Hashmap which means they won't be stored anywhere, not even in a temporary folder, unless you decide to.

See TempFile for more available data and information around uploaded files.