REST API Error: Content type 'application/octet-stream' not supported

Based on what I've found, yes, this appears to be a deliberate change in the FME Flow REST API v4 design rather than a bug.

When I upgraded to 26.1 I noted that v4 httpcaller upload action now expects a JSON or structured request body, rather than the simpler upload patterns commonly used in v3

This webinar is worth a watch Migrating FME Flow REST API Calls from V3 to V4 - FME by Safe Software

Also I found a Safe Software community discussion on v4 uploads states that:

"In API v4 ... support only the multipart form data"

for upload-style endpoints such as resource uploads and migration imports.

So instead of

Content-Type: application/octet-stream

use

Content-Type: multipart/form-data

preview what you intend to send, should look like 

curl -X POST \
  -H "Authorization: fmetoken token=XXXX" \
  -F "file=@MyWorkspace.fmw" \
  https://<flow>/fmeapiv4/repositories/MyRepo/items/upload

Thanks ​@j.botterill. Tried with multipart/form-data as well and getting the error message “The request body type was unexpected. Was expecting multipart/form-data."

When including the -F “file=${filename}” it returns a blank response. so may be an issue with how i’ve defined the content-disposition

Here’s what I’ve been sending through 

                response=$(curl -s -X POST \

                            -H "accept: application/json" \

                            -H "Content-Type: multipart/form-data" \

                            -H "Authorization: fmetoken token=${fmetoken}" \

                            -H "Content-Disposition: attachment; filename=\"${filename}\"" \

                            -F "files=${filename}" \

                                  --data-binary "@${filename}")

Awesome thanks for the help ​@j.botterill will try that out and hopefully can figure things out using that approach