SAP CAP - How to create an action for uploading files

[sub_han]

Hi,

I am trying to implement an endpoint that allows me to upload files from the browser.
Here is a sample fetch request from the client(browser)

const files =event.getParameter('files');
const file= files[0];
const formData =new FormData();
formData.append(file.name,file);
fetch({
  url:`/item/upload`,
  method:'POST',
  body: formData,
})

How do I implement this action in my .cds file.
It looks like this right now (simplified)

service ItemService {

type statusMessageType {
  ok      : Boolean;
  message:String;
  status: Integer;
  ID:String;
};
  action importEnvironment(fileId :String, envId :String, ver :String) returns statusMessageType;
  action deleteItem(ID:String) returns statusMessageType;
  action addFolder(folderName :String, currentFolderID :String) returns statusMessageType;
  action renameItem(sourceID :String, targetID :String) returns statusMessageType;
  
  action upload() returns statusMessageType;

}

How do I 'catch' the `formData` (body) in this `upload()` action as a parameter? And what type should it have? Binary?

Is this possible?

As a workaround I have implemented it as a normal express endpoint and it works in development.

But when I deploy my app to cloud foundry all my express implemented endpoints such as the following are not found and I get a 404 for them.

app.post('/upload');
app.get('/getItems');

Is this expected since we are not 'supposed' to do it like this?

[former_member771556]

Hi Subhan,
Do you have a solution to the above problem yet

[danilo_apicella1]

Taking your example as a reference, the upload action would need to have a parameter defined as type Binary or LargeBinary. Then, you would need a custom event handler for the action (https://cap.cloud.sap/docs/guides/providing-services#custom-event-handlers). The file would be accessible to you through the req argument of the handler, as one of its parameters (https://cap.cloud.sap/docs/node.js/events#params).

So a hypothetical custom event handler for your action "upload" with argument "file" of type LargeBinary would look like this:

this.on ('upload', (req)=>{
  const file = req.params.file;
  //file upload to s3
})

[shravan_pishike]

@danilo_apicella1 I do have the custom handler written in my code. But it is not triggered on the post call, I get the error before that itself.

I'm using CAP Java.