[feature] file params

[Dafaque]

Implement file picking and processing for Action Apps. Picking:

• sutable UI
• sending to backend as multipart or stream

Processing:

• param type ace.FILE (underlying stream, filename, and it's len i guess)
• some fs funcs to be able discover, store and read files
• make ace.result() to be able to accept new type, which causes download
• make http.in.post to be able handle new type into mulipart or stream request

For me use case is to create wrappers around some AI cmd's which has no REST. I want to:

• get file from form
• store it
• pass it's location into cmd
• await for result
• get result file and respond it back to user

[akclace]

Thanks for filing the ticket. I am taking a look at what changes are required for adding file upload/download support for Actions

[akclace]

Added display_type support in param definition, see https://github.com/claceio/clace/blob/fa8a97c5ab6435ee4edbdca14039156f9fd105c6/internal/app/tests/appaction_test.go#L867

For string types, display_type can be FILE/PASSWORD/TEXTAREA. For file, the file is uploaded and saved to a temp directory on the server. args.param_name will reference the temp file name on disk. It can be passed to exec.run to process the file data.

Multiple file type params are supported, each param supports single file upload only. The temp directory is deleted at the end of the action handler function.

Returning output file requires more work. If the run command generates a file on disk, referencing that file name directly will not work when multiple Clace servers are present behind a load balancer (since file will be on one of the machines). The plan is to add a fs.load_file API which will load file from disk to the Clace managed database. The ace.result will return a reference to that uploaded file, so that the API access will work from any machine.