HitchTrigger

HitchTrigger is a self contained build tool designed to trigger blocks of build commands when a condition is met that necessitates a rebuild.

The conditions can be one or more combined of any of the following:

• A file or files (e.g. source files) have changed.
• A specified (build) directory did not exist.
• A period of time has elapsed.
• A 'watched' variable has changed its value.
• An exception occurred the previous time the commands were run (always by default).

To install from pypi:

$ hitch install hitchtrigger

Use

import hitchtrigger

monitor = hitchtrigger.Monitor(
    "/path/to/project.watch"
    #override=["virtualenv", ],
)

# Will run in the following cases:
#
## The command block has never been run before.
## An exception was triggered within the context manager on the previous run.
## venv directory is non-existent.
## A period of 7 days has elapsed
## A previous block named 'previousblock' was run.
## Either requirements.txt or dev_requirements.txt have been modified (file modification dates are monitored).
## Var "v=1" is changed (e.g. to "v=2").
## The line 'override=["virtualenv", ]' is uncommented.

with monitor.block(
    "virtualenv",
    monitor.nonexistent("venv") | monitor.not_run_since(days=7) | monitor.was_run("previousblock")
    monitor.modified(["requirements.txt", "dev_requirements.txt"]) | monitor.var(v=1)
).context() as trigger:
    if trigger:
        print(trigger.why)  # Prints out reason for running

        Path("venv").rmtree(ignore_errors=True)
        virtualenv("venv").run()
        pip("install", "-r", "requirements.txt").run()
        pip("freeze").stdout(Path("freeze.txt")).run()
        pip("install", "dev_requirements.txt").run()