resurgence

Restart a process when files are changed

inspiration

File watchers are standard in many development workflows, but most utilities only handle execution of short-running processes (compilation, transpilation, formatting, linting). But what if the process runs infinitely?

When developing with PyQt for derivat and the curses for bible, I wanted to see how code changes would affect the graphical / terminal interface. I couldn't use standard file watchers, because they either

• would become unresponsive on first execution (application startup), never returning to to event loop and respond
• couldn't kill the previous process and thus would continuously spawn another application instance.

resurgence is a product of this need - kill the previous process, if still running, and execute the specified command again, using the updated application source.

requirements

• python 2.6+
• psutil

installation

$ pip install https://www.github.com/rwev/resurgence/archive/master.zip

usage

$ resurgence --help
resurgence.py [options]
Options:
  -h, --help            show this help message and exit
  -w, --cwd             Observe the current working directory
  -t REGEX_FILE_PATTERNS_TO_OBSERVE, --extensions=REGEX_FILE_PATTERNS_TO_OBSERVE
                        Comma-separated, spaceless list of file patterns to be
                        observed
  -d ADDITIONAL_SUBDIRECTORIES_TO_OBSERVE, --dirs=ADDITIONAL_SUBDIRECTORIES_TO_OBSERVE
                        Comma-separated, spaceless list of subdirectories
                        (below the working directory) to be observed
  -x COMMAND_TO_RUN_STR, --command=COMMAND_TO_RUN_STR
                        Command to run, restart on detected file changes, in
                        single quotes
  -i FILE_CHECK_INTERVAL_SECONDS, --interval=FILE_CHECK_INTERVAL_SECONDS
                        Interval in seconds between checks for file changes.

alternatives

• when-changed, also a Python utility, 3rd party dependency watchdog, can't restart processes
• entr, C utility, offers -r option to restart process, usable in Unix pipes