Post an parsed Mail-Attachment to API

General
1

Hey,
I've done my first steps with Node Red and got some experiences with it.
But now I stuck on the Problem, that the file won't be send to the API.
It seems the File-Content is missing.

But let's start from the beginning... what I have so far:

First of all, I have a flow, which parse my incomming Mails to find Emails, which are invoices and have an attachment.
(This part work like a charm).

It looks like this:

screenshot_10_00_47
screenshot_10_00_471236×435 58.5 KB

So far, so good. There you see the content of the file is an buffer with the Data.

So let's jump to the next flow, who should send this file to a REST-API. Thats what it looks like:

image
image932×190 21.1 KB

The Function-Node "API-Template" contain the following source-code.
Because of try & error, I tried two ways to construct the Payload:

FIRST (full written):

const { payload: {attachment} } = msg;
node.warn(msg)
        
const body = '----AaB03x\r\n'+
            'Content-Disposition: form-data; name="type"\r\n'+
            'voucher\r\n'+
            '----AaB03x\r\n'+
            'Content-Disposition: form-data; name="file"; filename="'+attachment.filename.replace(" ","")+'"\r\n'+
            'Content-Type: '+attachment.contentType+'\r\n'+
            'Content-Transfer-Encoding: binary\r\n'+
            attachment.content+'\r\n'+
            '\r\n'+
            '----AaB03x\r\n';
            
    const headers = {};
    headers["Content-Type"]="multipart/form-data; boundary=--AaB03x";
    headers["Authorization"]="Bearer <my-secret-token-stay-here>";
    headers["Accept"]="application/json";
    headers["Content-Length"]=body.length.toString();

return {payload:body, headers};

The Request for the First Try looks like this:

image
image705×583 68.8 KB

SECOND (as Object):

const { payload: {attachment} } = msg;
node.warn(msg)

msg.headers = {
    'Content-Type': 'multipart/form-data',
    'Authorization': 'Bearer <my-secret-token-stay-here>',
    'Content-Transfer-Encoding':'binary',
    'Content-Length': attachment.content.length.toString()
};
msg.payload = {
    'file' : {
        'value': attachment.content.toString('binary'),
        'options': {
            'filename': attachment.filename.replace(" ",""),
        },
    'type':'voucher'
    },
}

return msg

The Request for Second-Try looks like this:

image
image727×559 98 KB

But the API-Response for both requests is: statusCode: 500.

API-Documentation notice: If no file is provided, the file upload endpoint returns HTTP status 500 .

BTW: The above Requests are piped to http-request node which do a POST to the API-Endpoint.

So the question at all: What's wrong with the way I send the file-content. Did I miss something?