feat: add packaging setup (#9)

Author: zah

README.md

@@ -8,7 +8,21 @@ An unfinished prototype of a recorder of Python programs that produces [CodeTrac
 
 ### Usage
 
-you can currently use it directly with
+Install the package with `pip` or `uv`:
+
+```bash
+pip install codetracer-python-recorder
+```
+
+Then invoke the recorder as a command line tool:
+
+```bash
+codetracer-record <path to python file>
+# produces several trace json files in the current directory
+# or in the folder of `$CODETRACER_DB_TRACE_PATH` if such an env var is defined
+```
+
+During development you can also run it directly with
 
 ```bash
 python trace.py <path to python file>

pyproject.toml

@@ -0,0 +1,24 @@
+[build-system]
+requires = ["setuptools>=61"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "codetracer-python-recorder"
+version = "0.1.0"
+description = "Prototype recorder of Python programs producing CodeTracer traces"
+authors = [{name = "Metacraft Labs Ltd"}]
+license = {text = "MIT"}
+readme = "README.md"
+requires-python = ">=3.8"
+classifiers = [
+    "License :: OSI Approved :: MIT License",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3 :: Only",
+]
+
+[tool.setuptools]
+py-modules = ["trace"]
+package-dir = {"" = "src"}
+
+[project.scripts]
+codetracer-record = "trace:main"

src/trace.py

@@ -200,17 +200,23 @@ def local_trace(frame: types.FrameType, event: str, arg: Any):
     return tracer
 
 
-if __name__ == "__main__":
-    if len(sys.argv) < 2:
-        raise SystemExit("Usage: trace.py <program.py>")
+def main(argv: List[str] | None = None) -> None:
+    """Entry point for the command line interface."""
 
-    program_path = sys.argv[1]
+    if len(argv) < 1:
+        raise SystemExit("Usage: codetracer-record <program.py>")
+
+    program_path = argv[0]
     tracer = trace_program(program_path)
 
-    meta = {"workdir": os.getcwd(), "program": sys.argv[0], "args": sys.argv[1:]}
+    meta = {"workdir": os.getcwd(), "program": sys.argv[0], "args": argv}
     with open("trace_metadata.json", "w") as f:
         json.dump(meta, f, indent=2)
     with open("trace_paths.json", "w") as f:
         json.dump(tracer.paths, f, indent=2)
     with open("trace.json", "w") as f:
         json.dump(tracer.events, f, indent=2)
+
+
+if __name__ == "__main__":  # pragma: no cover - CLI passthrough
+    main(sys.argv[1:])