Question: Can PyInfra work with temporary files?

[mmartinortiz]

Hi,

After attending the FOSDEM 2026 talk about PyInfra I decided to start playing around and see how to provision my servers with PyInfra.

Normally, I manage the services on my remote servers with Docker Compose. There is a operation module for Docker, but not for Docker Compose, so I took the following approach:

• Upload a docker-compose.yaml file to the server.
• Upload an .env file with the secrets.
• Run docker compose up via a server.shell command with _sudo_user as an unprivileged user.

It works perfectly if the .env file exists on the machine that runs PyInfra, but I do not want that file to exist. Instead, I want to create a temporary file (like the one provided by NamedTemporaryFile) and populate it with the content to be uploaded as the .env file. I will pick up the secrets from environment variables (or from the command line, I still have to check if that is possible)

Either I use a context manager for the temporary file, or I create it and delete at the end of my Python file, the execution fails because by the time is read to be uploaded, it does not exist anymore. Probably, this is because the plan is done before executed.

Given that use case, is it possible to create temporal files to be uploaded to the remote server?

[mmartinortiz]

I'll, partially, answer myself: I do not know if you can work with temporal files, but you can make use of the io module; here is a snippet:

import io

env_file_content = """\
VAR_1=foo
VAR_2=bar
"""

files.put(
    src=io.StringIO(env_file_content),
    dest="/path/to/.env",
)

This will put/upload the content of env_file_content to a file on the server. Of course, you can do variable interpolation, make use of Pydantic Settings, environment variables, etc.

[Fizzadar]

This is the way (or tempfile).