Get rid of all transport types and settle on Protobuf (#25)

* Get rid of all transport types and settle on Protobuf

hope i don't regret this

* Update Cargo.toml

* Update agent.py

python/djls/commands.py

@@ -0,0 +1,209 @@
+from __future__ import annotations
+
+import importlib.metadata
+import os
+import sys
+import sysconfig
+from abc import ABC
+from abc import abstractmethod
+from typing import ClassVar
+from typing import Generic
+from typing import TypeVar
+
+from google.protobuf.message import Message
+
+from ._typing import override
+from .proto.v1 import check_pb2
+from .proto.v1 import django_pb2
+from .proto.v1 import python_pb2
+
+Request = TypeVar("Request", bound=Message)
+Response = TypeVar("Response", bound=Message)
+
+
+class Command(ABC, Generic[Request, Response]):
+    name: ClassVar[str]
+    request: ClassVar[type[Message]]
+    response: ClassVar[type[Message]]
+
+    def __init_subclass__(cls) -> None:
+        super().__init_subclass__()
+        class_vars = ["name", "request", "response"]
+        for class_var in class_vars:
+            if not hasattr(cls, class_var):
+                raise TypeError(
+                    f"Command subclass {cls.__name__} must define '{class_var}'"
+                )
+
+    @abstractmethod
+    def execute(self, request: Request) -> Response: ...
+
+
+class CheckHealth(Command[check_pb2.HealthRequest, check_pb2.HealthResponse]):
+    name = "check__health"
+    request = check_pb2.HealthRequest
+    response = check_pb2.HealthResponse
+
+    @override
+    def execute(self, request: check_pb2.HealthRequest) -> check_pb2.HealthResponse:
+        return check_pb2.HealthResponse(passed=True)
+
+
+class CheckDjangoAvailable(
+    Command[check_pb2.DjangoAvailableRequest, check_pb2.DjangoAvailableResponse]
+):
+    name = "check__django_available"
+    request = check_pb2.DjangoAvailableRequest
+    response = check_pb2.DjangoAvailableResponse
+
+    @override
+    def execute(
+        self, request: check_pb2.DjangoAvailableRequest
+    ) -> check_pb2.DjangoAvailableResponse:
+        try:
+            import django
+
+            return check_pb2.DjangoAvailableResponse(passed=True)
+        except ImportError:
+            return check_pb2.DjangoAvailableResponse(
+                passed=False, error="Django is not installed"
+            )
+
+
+class CheckAppInstalled(
+    Command[check_pb2.AppInstalledRequest, check_pb2.AppInstalledResponse]
+):
+    name = "check__app_installed"
+    request = check_pb2.AppInstalledRequest
+    response = check_pb2.AppInstalledResponse
+
+    @override
+    def execute(
+        self, request: check_pb2.AppInstalledRequest
+    ) -> check_pb2.AppInstalledResponse:
+        try:
+            from django.apps import apps
+
+            return check_pb2.AppInstalledResponse(
+                passed=apps.is_installed(request.app_name)
+            )
+        except ImportError:
+            return check_pb2.AppInstalledResponse(
+                passed=False, error="Django is not installed"
+            )
+
+
+class PythonGetEnvironment(
+    Command[python_pb2.GetEnvironmentRequest, python_pb2.GetEnvironmentResponse]
+):
+    name = "python__get_environment"
+    request = python_pb2.GetEnvironmentRequest
+    response = python_pb2.GetEnvironmentResponse
+
+    @override
+    def execute(
+        self, request: python_pb2.GetEnvironmentRequest
+    ) -> python_pb2.GetEnvironmentResponse:
+        packages = {}
+        for dist in importlib.metadata.distributions():
+            try:
+                requires = []
+                try:
+                    requires = list(dist.requires) if hasattr(dist, "requires") else []
+                except Exception:
+                    pass
+
+                location = None
+                try:
+                    location = str(dist._path) if hasattr(dist, "_path") else None
+                except Exception:
+                    pass
+
+                packages[dist.metadata["Name"]] = python_pb2.Package(
+                    dist_name=dist.metadata["Name"],
+                    dist_version=dist.metadata["Version"],
+                    dist_location=location,
+                    dist_requires=requires,
+                    dist_requires_python=dist.metadata.get("Requires-Python"),
+                    dist_entry_points=str(dist.entry_points)
+                    if hasattr(dist, "entry_points")
+                    else None,
+                )
+            except Exception:
+                continue
+
+        sysconfig_paths = sysconfig.get_paths()
+
+        version_info = python_pb2.VersionInfo(
+            major=sys.version_info.major,
+            minor=sys.version_info.minor,
+            micro=sys.version_info.micro,
+            releaselevel={
+                "alpha": python_pb2.ReleaseLevel.ALPHA,
+                "beta": python_pb2.ReleaseLevel.BETA,
+                "candidate": python_pb2.ReleaseLevel.CANDIDATE,
+                "final": python_pb2.ReleaseLevel.FINAL,
+            }[sys.version_info.releaselevel],
+            serial=sys.version_info.serial,
+        )
+
+        return python_pb2.GetEnvironmentResponse(
+            python=python_pb2.Python(
+                os=python_pb2.Os(environ={k: v for k, v in os.environ.items()}),
+                site=python_pb2.Site(packages=packages),
+                sys=python_pb2.Sys(
+                    debug_build=hasattr(sys, "gettotalrefcount"),
+                    dev_mode=sys.flags.dev_mode,
+                    is_venv=sys.prefix != sys.base_prefix,
+                    abiflags=sys.abiflags,
+                    base_prefix=sys.base_prefix,
+                    default_encoding=sys.getdefaultencoding(),
+                    executable=sys.executable,
+                    filesystem_encoding=sys.getfilesystemencoding(),
+                    implementation_name=sys.implementation.name,
+                    platform=sys.platform,
+                    prefix=sys.prefix,
+                    builtin_module_names=list(sys.builtin_module_names),
+                    dll_paths=sys.path if sys.platform == "win32" else [],
+                    path=sys.path,
+                    version_info=version_info,
+                ),
+                sysconfig=python_pb2.Sysconfig(
+                    data=sysconfig_paths.get("data", ""),
+                    include=sysconfig_paths.get("include", ""),
+                    platinclude=sysconfig_paths.get("platinclude", ""),
+                    platlib=sysconfig_paths.get("platlib", ""),
+                    platstdlib=sysconfig_paths.get("platstdlib", ""),
+                    purelib=sysconfig_paths.get("purelib", ""),
+                    scripts=sysconfig_paths.get("scripts", ""),
+                    stdlib=sysconfig_paths.get("stdlib", ""),
+                ),
+            )
+        )
+
+
+class DjangoGetProjectInfo(
+    Command[django_pb2.GetProjectInfoRequest, django_pb2.GetProjectInfoResponse]
+):
+    name = "django__get_project_info"
+    request = django_pb2.GetProjectInfoRequest
+    response = django_pb2.GetProjectInfoResponse
+
+    @override
+    def execute(
+        self, request: django_pb2.GetProjectInfoRequest
+    ) -> django_pb2.GetProjectInfoResponse:
+        import django
+
+        return django_pb2.GetProjectInfoResponse(
+            project=django_pb2.Project(version=django.__version__)
+        )
+
+
+COMMANDS = [
+    CheckAppInstalled,
+    CheckDjangoAvailable,
+    CheckHealth,
+    PythonGetEnvironment,
+    DjangoGetProjectInfo,
+]