This http call imports a flow file into H2O Flow. First the raw curl command, second the corresponding IntelliJ http file

import-flow.http

###

POST http://localhost:54321/3/NodePersistentStorage.bin/notebook/my-model
Content-Type: multipart/form-data; boundary=WebAppBoundary

--WebAppBoundary
Content-Disposition: form-data; name="file"; filename="my-model.flow"

< path/to/my-model.flow
--WebAppBoundary--

###

import-flow.sh

    curl http://localhost:54321/3/NodePersistentStorage.bin/notebook/my-model \
         -H "Content-Type: multipart/form-data" \
         -F "file=@path/to/my-model.flow"