feat: basically finish pkgconfig generation

packer/src/sarasacw_omrf_packer/metadata.py

@@ -0,0 +1,60 @@
+import json
+import subprocess
+from typing import Any
+from pathlib import Path
+import tomli
+
+
+# YYC MARK:
+# We use `tomli` with at least 2.4.0 version by design.
+# Considering that Cargo has approve the change allowing TOML 1.1 syntax in `Cargo.toml`,
+# Python embedded `toml` package, which only support TOML 1.0 syntax until Python 3.15,
+# is not suit for parsing `Cargo.toml` in future.
+# So we use the upstream of official `toml` package, i.e. `tomli` as our solution.
+# And according to the document if `tomli`, the version starting support TOML 1.1 syntax is 2.4.0.
+
+_TOKEN_PACKAGES: str = "packages"
+_TOKEN_PACKAGE_MANIFEST_PATH: str = "manifest_path"
+_TOKEN_TARGET_DIRECTORY: str = "target_directory"
+
+
+class Metadata:
+    __cargo_toml_path: Path
+    __cargo_metadata: dict[str, Any]
+    __cargo_toml: dict[str, Any]
+
+    def __init__(self, cargo_toml: Path) -> None:
+        self.__cargo_toml_path = cargo_toml
+        self.__cargo_toml = Metadata.__extract_cargo_toml(cargo_toml)
+        self.__cargo_metadata = Metadata.__extract_cargo_metadata(cargo_toml)
+
+    @staticmethod
+    def __extract_cargo_toml(cargo_toml: Path) -> dict[str, Any]:
+        with open(cargo_toml, "rb") as f:
+            return tomli.load(f)
+
+    @staticmethod
+    def __extract_cargo_metadata(cargo_toml: Path) -> dict[str, Any]:
+        cmd = [
+            "cargo",
+            "metadata",
+            "--no-deps",
+            "--format-version",
+            "1",
+            "--manifest-path",
+            str(cargo_toml),
+        ]
+        proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        try:
+            stdout, stderr = proc.communicate(timeout=10)
+        except subprocess.TimeoutExpired:
+            proc.kill()
+            proc.communicate()
+            raise RuntimeError("fail to fetch cargo metadata: timed out")
+        if proc.returncode != 0:
+            raise RuntimeError(
+                "fail to fetch cargo metadata: "
+                + stderr.decode("utf-8", errors="ignore")
+            )
+        else:
+            return json.loads(stdout)