Merge pull request aiokitchen#181 from aiokitchen/feature/grpc-server…

…-service

GRPC service

aiomisc/service/grpc_server.py

@@ -0,0 +1,108 @@
+import asyncio
+import logging
+import re
+import sys
+from concurrent.futures import Executor
+from types import MappingProxyType
+from typing import Any, Optional, Sequence, Set, Tuple
+
+from .base import Service
+
+
+try:
+    import grpc.aio
+except ImportError as e:
+    raise ImportError(
+        "You must install 'grpcio' manually or using extras 'aiomisc[grpc]'",
+    ) from e
+
+log = logging.getLogger(__name__)
+
+if sys.version_info >= (3, 9):
+    PortFuture = asyncio.Future[int]
+else:
+    PortFuture = asyncio.Future
+
+
+class GRPCService(Service):
+    GRACEFUL_STOP_TIME: float = 60.
+
+    _ADDRESS_REGEXP = re.compile(
+        r"(?P<address>(\[((([([0-9a-fA-F:]*)+)])?|([\w.]+))):(\d+)",
+    )
+
+    _server: grpc.aio.Server
+    _server_args: MappingProxyType
+    _insecure_ports: Set[Tuple[str, PortFuture]]
+    _secure_ports: Set[Tuple[str, grpc.ServerCredentials, PortFuture]]
+
+    def __init__(
+        self, *,
+        migration_thread_pool: Optional[Executor] = None,
+        handlers: Optional[Sequence[grpc.GenericRpcHandler]] = None,
+        interceptors: Optional[Sequence[Any]] = None,
+        options: Optional[Sequence[Tuple[str, Any]]] = None,
+        maximum_concurrent_rpcs: Optional[int] = None,
+        compression: Optional[grpc.Compression] = None,
+        **kwds: Any,
+    ):
+        self._server_args = MappingProxyType({
+            "compression": compression,
+            "handlers": handlers,
+            "interceptors": interceptors,
+            "maximum_concurrent_rpcs": maximum_concurrent_rpcs,
+            "migration_thread_pool": migration_thread_pool,
+            "options": options,
+        })
+        self._services: Set[grpc.GenericRpcHandler] = set()
+        self._insecure_ports = set()
+        self._secure_ports = set()
+        super().__init__(**kwds)
+
+    @classmethod
+    def _log_port(cls, msg: str, address: str, bind_port: Any) -> None:
+        match: Optional[re.Match] = cls._ADDRESS_REGEXP.match(address)
+
+        if match is not None:
+            groups = match.groupdict()
+            address = groups["address"]
+
+        log.info("%s: grpc://%s:%s", msg, address, bind_port)
+
+    async def start(self) -> None:
+        self._server = grpc.aio.server(**self._server_args)
+
+        for address, future in self._insecure_ports:
+            port = self._server.add_insecure_port(address)
+            future.set_result(port)
+            self._log_port("Listening insecure address", address, port)
+
+        for address, credentials, future in self._secure_ports:
+            port = self._server.add_secure_port(address, credentials)
+            future.set_result(port)
+            self._log_port("Listening secure address", address, port)
+
+        self._server.add_generic_rpc_handlers(tuple(self._services))
+        await self._server.start()
+
+    async def stop(self, exception: Optional[Exception] = None) -> None:
+        await self._server.stop(self.GRACEFUL_STOP_TIME)
+
+    def add_generic_rpc_handlers(
+        self, generic_rpc_handlers: Sequence[grpc.GenericRpcHandler],
+    ) -> None:
+        for service in generic_rpc_handlers:
+            self._services.add(service)
+
+    def add_insecure_port(self, address: str) -> PortFuture:
+        future: PortFuture = asyncio.Future()
+        self._insecure_ports.add((address, future))
+        return future
+
+    def add_secure_port(
+        self, address: str,
+        server_credentials: grpc.ServerCredentials,
+    ) -> PortFuture:
+        future: PortFuture = asyncio.Future()
+        self._secure_ports.add((address, server_credentials, future))
+        return future

docs/source/services.rst

@@ -666,6 +666,79 @@ Class ``ASGIHTTPSSLService`` is similar to ``ASGIHTTPService`` but creates
 HTTPS server. You must pass SSL-required options (see ``TLSServer`` class).
 
 
+.. _grpc-service::
+
+GRPC service
+++++++++++++
+
+This is an example of a GRPC service which is defined in a file and loads a
+`hello.proto` file without code generation, this example is one of the examples
+from `grpcio`, the other examples will work as expected.
+
+Proto definition:
+
+.. code-block::
+
+    syntax = "proto3";
+
+    package helloworld;
+
+    // The greeting service definition.
+    service Greeter {
+      // Sends a greeting
+      rpc SayHello (HelloRequest) returns (HelloReply) {}
+    }
+
+    // The request message containing the user's name.
+    message HelloRequest {
+      string name = 1;
+    }
+
+    // The response message containing the greetings
+    message HelloReply {
+      string message = 1;
+    }
+
+
+Service initialization example:
+
+
+.. code-block:: python
+
+    import grpc
+
+    import aiomisc
+    from aiomisc.service.grpc_server import GRPCService
+
+
+    protos, services = grpc.protos_and_services("hello.proto")
+
+
+    class Greeter(services.GreeterServicer):
+        async def SayHello(self, request, context):
+            return protos.HelloReply(message='Hello, %s!' % request.name)
+
+
+    def main():
+        grpc_service = GRPCService(compression=grpc.Compression.Gzip)
+        services.add_GreeterServicer_to_server(
+            Greeter(), grpc_service,
+        )
+        grpc_service.add_insecure_port('[::]:0')
+        grpc_service.add_insecure_port('[::1]:0')
+        grpc_service.add_insecure_port('127.0.0.1:0')
+        grpc_service.add_insecure_port('localhost:0')
+        grpc_service.add_secure_port('localhost:0', grpc.local_server_credentials())
+        grpc_service.add_secure_port('[::]:0', grpc.local_server_credentials())
+
+        with aiomisc.entrypoint(grpc_service) as loop:
+            loop.run_forever()
+
+
+    if __name__ == '__main__':
+        main()
+
+
 .. _memory-tracer:
 
 Memory Tracer