python: script to build python package

python/scripts/build_python_package.py

@@ -0,0 +1,156 @@
+#!/usr/bin/env python
+# Copyright 2023-2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import re
+import subprocess
+import sys
+from pathlib import Path
+
+import click
+
+
+@click.command()
+def main() -> None:
+    repo_root_dir = Path(__file__).parent.parent.parent
+    python_root_dir = repo_root_dir / "python"
+    dist_output_dir = python_root_dir / "dist"
+    rust_root_dir = repo_root_dir / "rust"
+    # Compute paths to files we'll need to restore at the end of the build
+    rust_cli_readme_path = rust_root_dir / "cli" / "README.md"
+    rust_main_rs_path = rust_root_dir / "cli" / "src" / "main.rs"
+    rust_cli_cargo_toml_path = rust_root_dir / "cli" / "Cargo.toml"
+    rust_cli_cargo_lock_path = rust_root_dir / "cli" / "Cargo.lock"
+
+    r = subprocess.run(
+        ["git", "status", "--porcelain"], capture_output=True, cwd=repo_root_dir
+    )
+    if len(r.stdout) > 0 or len(r.stderr) > 0:
+        print("ERROR: the git repository is in a dirty state.")
+        sys.exit(1)
+
+    # delete readme as it causes issues with sdist; we'll restore it later
+    rust_cli_readme_path.unlink()
+
+    try:
+        # get the rust version from Cargo.toml and patch main.rs
+        rust_version = get_rust_version(rust_root_dir)
+        patch_main_rs_with_version(rust_main_rs_path, rust_version)
+
+        # get the python version from magika.__version__ and patch Cargo.toml
+        python_version = get_python_version(python_root_dir)
+        patch_cargo_toml_with_version(rust_cli_cargo_toml_path, python_version)
+
+        # update Cargo.lock
+        r = subprocess.run(
+            ["cargo", "check"],
+            cwd=rust_root_dir / "cli",
+        )
+
+        # build the package
+        r = subprocess.run(
+            ["uv", "build", "--out-dir", str(dist_output_dir)],
+            cwd=python_root_dir,
+        )
+        print(f"Python packages built at {dist_output_dir}")
+    finally:
+        # restore what we modified, no matter what happened
+        r = subprocess.run(
+            [
+                "git",
+                "restore",
+                "--",
+                str(rust_cli_readme_path),
+                str(rust_main_rs_path),
+                str(rust_cli_cargo_toml_path),
+                str(rust_cli_cargo_lock_path),
+            ],
+            capture_output=True,
+            cwd=repo_root_dir,
+        )
+
+
+def get_rust_version(rust_root_dir: Path) -> str:
+    cargo_path = rust_root_dir / "cli" / "Cargo.toml"
+    version = extract_with_regex(cargo_path, 'version = "([A-Za-z0-9.-]+)".*')
+    print(f"Extracted rust version: {version}")
+    return version
+
+
+def get_python_version(python_root_dir: Path) -> str:
+    init_path = python_root_dir / "src" / "magika" / "__init__.py"
+    version = extract_with_regex(init_path, '__version__ = "([A-Za-z0-9.-]+)"')
+    print(f"Extracted python version: {version}")
+    return version
+
+
+def patch_main_rs_with_version(rust_main_rs_path: Path, version: str) -> None:
+    print(f'Patching {rust_main_rs_path} with rust version "{version}"')
+    patch_line_matching_prefix(
+        rust_main_rs_path,
+        "        let binary = clap::crate_version!();",
+        f'        let binary = "{version}";',
+    )
+
+
+def patch_cargo_toml_with_version(cargo_toml_path: Path, version: str) -> None:
+    print(f'Patching {cargo_toml_path} with python version "{version}"')
+    patch_line_matching_prefix(cargo_toml_path, "version = ", f'version = "{version}"')
+
+
+def extract_with_regex(file_path: Path, regex: str) -> str:
+    """Extract a string via regex. This raises an exception if no or more than
+    one matches are found."""
+
+    lines = file_path.read_text().split("\n")
+    output = None
+    for line in lines:
+        m = re.fullmatch(regex, line)
+        if m:
+            if output is not None:
+                raise Exception(
+                    f'ERROR: Found more than one match for "{regex}" in {file_path}'
+                )
+            output = m.group(1)
+    if output is None:
+        raise Exception(f'No hits for "{regex}" in {file_path}')
+    return output
+
+
+def patch_line_matching_prefix(file_path: Path, prefix: str, new_line: str) -> None:
+    """Patch a line starting with a given prefix with a new line. This raises an
+    exception if no such line or more than one lines with a given prefix are
+    found."""
+
+    lines = file_path.read_text().split("\n")
+    already_found = False
+    for line_idx in range(len(lines)):
+        line = lines[line_idx]
+        if line.startswith(prefix):
+            if already_found:
+                raise Exception(
+                    f'ERROR: Found more than one line with prefix "{prefix}" in "{file_path}"'
+                )
+            already_found = True
+            lines[line_idx] = new_line
+
+    if not already_found:
+        raise Exception(
+            f'ERROR: Did not find any line with prefix "{prefix}" in "{file_path}"'
+        )
+    file_path.write_text("\n".join(lines))
+
+
+if __name__ == "__main__":
+    main()