Added install/uninstall commands for pre-push hook

clickusagemd.py

@@ -6,6 +6,8 @@ from typing import Iterator
 import click
 import toml
 
+from lib.githook import install_hook, uninstall_hook
+
 
 def iter_commands(
     module_name: str,
@@ -55,10 +57,14 @@ def generate_usage_md(script: str, version: str):
             print(command, file=fd)
 
 
-@click.command()
-@click.argument("poetry_project_file", type=click.File())
-@click.pass_context
-def cli(ctx, poetry_project_file):
+@click.group()
+def cli():
+    pass
+
+
+@cli.command(help="Generate markdown usage description.")
+@click.argument("poetry_project_file", type=click.File(), default="pyproject.toml")
+def run(ctx, poetry_project_file):
     contents = toml.loads(poetry_project_file.read())
     try:
         scripts = contents["tool"]["poetry"]["scripts"]
@@ -70,5 +76,20 @@ def cli(ctx, poetry_project_file):
         ctx.exit(1)
 
 
+@cli.command(help="Install clickusagemd as pre-push hook.")
+def install():
+    install_hook("./")
+
+
+@cli.command(help="Uninstall clickusagemd pre-push hook.")
+def uninstall():
+    uninstall_hook("./")
+
+
+cli.add_command(run)
+cli.add_command(install)
+cli.add_command(uninstall)
+
+
 if __name__ == "__main__":
     cli()

lib/githook.py

@@ -0,0 +1,68 @@
+import hashlib
+from pathlib import Path
+
+PRE_PUSH_SCRIPT = """#!/bin/sh
+
+if [[ ! -z "$VIRTUAL_ENV" ]]
+then
+    while read -d $'\0' arg ; do
+        echo $arg
+        if [[ "$arg" == '--follow-tags' ]] ; then
+            clickusagemd ${GIT_DIR}pyproject.toml || exit 1
+            git add ${GIT_DIR}USAGE.md || exit 1
+            git commit -m"Autogenerated USAGE.md updated and added."
+            exit 0
+        fi
+    done < /proc/$PPID/cmdline
+fi
+
+exit 0
+"""
+
+
+def is_gitdir(func):
+    def path_check(*args, **kwargs) -> bool:  # dead: disable
+        path = Path(args[0] or "./") / ".git/hooks"
+        if path.exists():
+            return func(path)
+        else:
+            return False
+
+    return path_check
+
+
+@is_gitdir
+def install_hook(path: Path) -> bool:
+    githook = path / "pre-push"
+    if not githook.exists():
+        with githook.open("wt") as fd:
+            fd.write(PRE_PUSH_SCRIPT)
+            fd.close()
+            githook.chmod(0o755)
+            print(f"Hook installed as `{githook}'.")
+            return True
+    else:
+        print(f"A hook is already installed as `{githook}'. Installation aborted.")
+    return False
+
+
+@is_gitdir
+def uninstall_hook(path: Path) -> bool:
+    githook = path / "pre-push"
+    if githook.exists():
+        sha256_hook = hashlib.new("sha256")
+        with githook.open("rb") as fd:
+            sha256_hook.update(fd.read())
+        sha256_const = hashlib.new("sha256")
+        sha256_const.update(PRE_PUSH_SCRIPT.encode("utf-8"))
+
+        if sha256_const.digest() == sha256_hook.digest():
+            githook.unlink()
+            print(f"Hook `{githook}' uninstalled.")
+            return True
+        else:
+            print("The file seems not to be the a clickusagemd hook.")
+    else:
+        print("The clickusagemd hook is not installed.")
+
+    return False