Merge pull request #83 from nat-n/client-streaming

Client streaming

.gitignore

@@ -12,4 +12,5 @@ dist
 **/*.egg-info
 output
 .idea
+.DS_Store
 .tox

betterproto/__init__.py

@@ -5,8 +5,9 @@ import json
 import struct
 import sys
 from abc import ABC
-from base64 import b64encode, b64decode
+from base64 import b64decode, b64encode
 from datetime import datetime, timedelta, timezone
+import stringcase
 from typing import (
     Any,
     AsyncGenerator,
@@ -14,28 +15,20 @@ from typing import (
     Collection,
     Dict,
     Generator,
+    Iterator,
     List,
     Mapping,
     Optional,
     Set,
+    SupportsBytes,
     Tuple,
     Type,
-    TypeVar,
     Union,
     get_type_hints,
-    TYPE_CHECKING,
 )
-
+from ._types import ST, T
-
-import grpclib.const
-import stringcase
-
 from .casing import safe_snake_case
-
+from .grpc.grpclib_client import ServiceStub
-if TYPE_CHECKING:
-    from grpclib._protocols import IProtoMessage
-    from grpclib.client import Channel
-    from grpclib.metadata import Deadline
 
 if not (sys.version_info.major == 3 and sys.version_info.minor >= 7):
     # Apply backport of datetime.fromisoformat from 3.7
@@ -429,10 +422,6 @@ def parse_fields(value: bytes) -> Generator[ParsedField, None, None]:
         )
 
 
-# Bound type variable to allow methods to return `self` of subclasses
-T = TypeVar("T", bound="Message")
-
-
 class ProtoClassMetadata:
     oneof_group_by_field: Dict[str, str]
     oneof_field_by_group: Dict[str, Set[dataclasses.Field]]
@@ -451,7 +440,7 @@ class ProtoClassMetadata:
 
     def __init__(self, cls: Type["Message"]):
         by_field = {}
-        by_group = {}
+        by_group: Dict[str, Set] = {}
         by_field_name = {}
         by_field_number = {}
 
@@ -604,7 +593,7 @@ class Message(ABC):
             serialize_empty = False
             if isinstance(value, Message) and value._serialized_on_wire:
                 # Empty messages can still be sent on the wire if they were
-                # set (or received empty).
+                # set (or recieved empty).
                 serialize_empty = True
 
             if value == self._get_field_default(field_name) and not (
@@ -791,7 +780,7 @@ class Message(ABC):
 
     def to_dict(
         self, casing: Casing = Casing.CAMEL, include_default_values: bool = False
-    ) -> dict:
+    ) -> Dict[str, Any]:
         """
         Returns a dict representation of this message instance which can be
         used to serialize to e.g. JSON. Defaults to camel casing for
@@ -1024,83 +1013,3 @@ def _get_wrapper(proto_type: str) -> Type:
         TYPE_STRING: StringValue,
         TYPE_BYTES: BytesValue,
     }[proto_type]
-
-
-_Value = Union[str, bytes]
-_MetadataLike = Union[Mapping[str, _Value], Collection[Tuple[str, _Value]]]
-
-
-class ServiceStub(ABC):
-    """
-    Base class for async gRPC service stubs.
-    """
-
-    def __init__(
-        self,
-        channel: "Channel",
-        *,
-        timeout: Optional[float] = None,
-        deadline: Optional["Deadline"] = None,
-        metadata: Optional[_MetadataLike] = None,
-    ) -> None:
-        self.channel = channel
-        self.timeout = timeout
-        self.deadline = deadline
-        self.metadata = metadata
-
-    def __resolve_request_kwargs(
-        self,
-        timeout: Optional[float],
-        deadline: Optional["Deadline"],
-        metadata: Optional[_MetadataLike],
-    ):
-        return {
-            "timeout": self.timeout if timeout is None else timeout,
-            "deadline": self.deadline if deadline is None else deadline,
-            "metadata": self.metadata if metadata is None else metadata,
-        }
-
-    async def _unary_unary(
-        self,
-        route: str,
-        request: "IProtoMessage",
-        response_type: Type[T],
-        *,
-        timeout: Optional[float] = None,
-        deadline: Optional["Deadline"] = None,
-        metadata: Optional[_MetadataLike] = None,
-    ) -> T:
-        """Make a unary request and return the response."""
-        async with self.channel.request(
-            route,
-            grpclib.const.Cardinality.UNARY_UNARY,
-            type(request),
-            response_type,
-            **self.__resolve_request_kwargs(timeout, deadline, metadata),
-        ) as stream:
-            await stream.send_message(request, end=True)
-            response = await stream.recv_message()
-            assert response is not None
-            return response
-
-    async def _unary_stream(
-        self,
-        route: str,
-        request: "IProtoMessage",
-        response_type: Type[T],
-        *,
-        timeout: Optional[float] = None,
-        deadline: Optional["Deadline"] = None,
-        metadata: Optional[_MetadataLike] = None,
-    ) -> AsyncGenerator[T, None]:
-        """Make a unary request and return the stream response iterator."""
-        async with self.channel.request(
-            route,
-            grpclib.const.Cardinality.UNARY_STREAM,
-            type(request),
-            response_type,
-            **self.__resolve_request_kwargs(timeout, deadline, metadata),
-        ) as stream:
-            await stream.send_message(request, end=True)
-            async for message in stream:
-                yield message

betterproto/_types.py

@@ -0,0 +1,9 @@
+from typing import TYPE_CHECKING, TypeVar
+
+if TYPE_CHECKING:
+    from . import Message
+    from grpclib._protocols import IProtoMessage
+
+# Bound type variable to allow methods to return `self` of subclasses
+T = TypeVar("T", bound="Message")
+ST = TypeVar("ST", bound="IProtoMessage")

betterproto/grpc/grpclib_client.py

@@ -0,0 +1,170 @@
+from abc import ABC
+import asyncio
+import grpclib.const
+from typing import (
+    Any,
+    AsyncIterable,
+    AsyncIterator,
+    Collection,
+    Iterable,
+    Mapping,
+    Optional,
+    Tuple,
+    TYPE_CHECKING,
+    Type,
+    Union,
+)
+from .._types import ST, T
+
+if TYPE_CHECKING:
+    from grpclib._protocols import IProtoMessage
+    from grpclib.client import Channel, Stream
+    from grpclib.metadata import Deadline
+
+
+_Value = Union[str, bytes]
+_MetadataLike = Union[Mapping[str, _Value], Collection[Tuple[str, _Value]]]
+_MessageSource = Union[Iterable["IProtoMessage"], AsyncIterable["IProtoMessage"]]
+
+
+class ServiceStub(ABC):
+    """
+    Base class for async gRPC clients.
+    """
+
+    def __init__(
+        self,
+        channel: "Channel",
+        *,
+        timeout: Optional[float] = None,
+        deadline: Optional["Deadline"] = None,
+        metadata: Optional[_MetadataLike] = None,
+    ) -> None:
+        self.channel = channel
+        self.timeout = timeout
+        self.deadline = deadline
+        self.metadata = metadata
+
+    def __resolve_request_kwargs(
+        self,
+        timeout: Optional[float],
+        deadline: Optional["Deadline"],
+        metadata: Optional[_MetadataLike],
+    ):
+        return {
+            "timeout": self.timeout if timeout is None else timeout,
+            "deadline": self.deadline if deadline is None else deadline,
+            "metadata": self.metadata if metadata is None else metadata,
+        }
+
+    async def _unary_unary(
+        self,
+        route: str,
+        request: "IProtoMessage",
+        response_type: Type[T],
+        *,
+        timeout: Optional[float] = None,
+        deadline: Optional["Deadline"] = None,
+        metadata: Optional[_MetadataLike] = None,
+    ) -> T:
+        """Make a unary request and return the response."""
+        async with self.channel.request(
+            route,
+            grpclib.const.Cardinality.UNARY_UNARY,
+            type(request),
+            response_type,
+            **self.__resolve_request_kwargs(timeout, deadline, metadata),
+        ) as stream:
+            await stream.send_message(request, end=True)
+            response = await stream.recv_message()
+            assert response is not None
+            return response
+
+    async def _unary_stream(
+        self,
+        route: str,
+        request: "IProtoMessage",
+        response_type: Type[T],
+        *,
+        timeout: Optional[float] = None,
+        deadline: Optional["Deadline"] = None,
+        metadata: Optional[_MetadataLike] = None,
+    ) -> AsyncIterator[T]:
+        """Make a unary request and return the stream response iterator."""
+        async with self.channel.request(
+            route,
+            grpclib.const.Cardinality.UNARY_STREAM,
+            type(request),
+            response_type,
+            **self.__resolve_request_kwargs(timeout, deadline, metadata),
+        ) as stream:
+            await stream.send_message(request, end=True)
+            async for message in stream:
+                yield message
+
+    async def _stream_unary(
+        self,
+        route: str,
+        request_iterator: _MessageSource,
+        request_type: Type[ST],
+        response_type: Type[T],
+        *,
+        timeout: Optional[float] = None,
+        deadline: Optional["Deadline"] = None,
+        metadata: Optional[_MetadataLike] = None,
+    ) -> T:
+        """Make a stream request and return the response."""
+        async with self.channel.request(
+            route,
+            grpclib.const.Cardinality.STREAM_UNARY,
+            request_type,
+            response_type,
+            **self.__resolve_request_kwargs(timeout, deadline, metadata),
+        ) as stream:
+            await self._send_messages(stream, request_iterator)
+            response = await stream.recv_message()
+            assert response is not None
+            return response
+
+    async def _stream_stream(
+        self,
+        route: str,
+        request_iterator: _MessageSource,
+        request_type: Type[ST],
+        response_type: Type[T],
+        *,
+        timeout: Optional[float] = None,
+        deadline: Optional["Deadline"] = None,
+        metadata: Optional[_MetadataLike] = None,
+    ) -> AsyncIterator[T]:
+        """
+        Make a stream request and return an AsyncIterator to iterate over response
+        messages.
+        """
+        async with self.channel.request(
+            route,
+            grpclib.const.Cardinality.STREAM_STREAM,
+            request_type,
+            response_type,
+            **self.__resolve_request_kwargs(timeout, deadline, metadata),
+        ) as stream:
+            await stream.send_request()
+            sending_task = asyncio.ensure_future(
+                self._send_messages(stream, request_iterator)
+            )
+            try:
+                async for response in stream:
+                    yield response
+            except:
+                sending_task.cancel()
+                raise
+
+    @staticmethod
+    async def _send_messages(stream, messages: _MessageSource):
+        if isinstance(messages, AsyncIterable):
+            async for message in messages:
+                await stream.send_message(message)
+        else:
+            for message in messages:
+                await stream.send_message(message)
+        await stream.end()

betterproto/grpc/util/async_channel.py

@@ -0,0 +1,198 @@
+import asyncio
+from typing import (
+    AsyncIterable,
+    AsyncIterator,
+    Iterable,
+    Optional,
+    TypeVar,
+    Union,
+)
+
+T = TypeVar("T")
+
+
+class ChannelClosed(Exception):
+    """
+    An exception raised on an attempt to send through a closed channel
+    """
+
+    pass
+
+
+class ChannelDone(Exception):
+    """
+    An exception raised on an attempt to send recieve from a channel that is both closed
+    and empty.
+    """
+
+    pass
+
+
+class AsyncChannel(AsyncIterable[T]):
+    """
+    A buffered async channel for sending items between coroutines with FIFO ordering.
+
+    This makes decoupled bidirection steaming gRPC requests easy if used like:
+
+    .. code-block:: python
+        client = GeneratedStub(grpclib_chan)
+        request_chan = await AsyncChannel()
+        # We can start be sending all the requests we already have
+        await request_chan.send_from([ReqestObject(...), ReqestObject(...)])
+        async for response in client.rpc_call(request_chan):
+            # The response iterator will remain active until the connection is closed
+            ...
+            # More items can be sent at any time
+            await request_chan.send(ReqestObject(...))
+            ...
+            # The channel must be closed to complete the gRPC connection
+            request_chan.close()
+
+    Items can be sent through the channel by either:
+    - providing an iterable to the send_from method
+    - passing them to the send method one at a time
+
+    Items can be recieved from the channel by either:
+    - iterating over the channel with a for loop to get all items
+    - calling the recieve method to get one item at a time
+
+    If the channel is empty then recievers will wait until either an item appears or the
+    channel is closed.
+
+    Once the channel is closed then subsequent attempt to send through the channel will
+    fail with a ChannelClosed exception.
+
+    When th channel is closed and empty then it is done, and further attempts to recieve
+    from it will fail with a ChannelDone exception
+
+    If multiple coroutines recieve from the channel concurrently, each item sent will be
+    recieved by only one of the recievers.
+
+    :param source:
+        An optional iterable will items that should be sent through the channel
+        immediately.
+    :param buffer_limit:
+        Limit the number of items that can be buffered in the channel, A value less than
+        1 implies no limit. If the channel is full then attempts to send more items will
+        result in the sender waiting until an item is recieved from the channel.
+    :param close:
+        If set to True then the channel will automatically close after exhausting source
+        or immediately if no source is provided.
+    """
+
+    def __init__(
+        self, *, buffer_limit: int = 0, close: bool = False,
+    ):
+        self._queue: asyncio.Queue[Union[T, object]] = asyncio.Queue(buffer_limit)
+        self._closed = False
+        self._waiting_recievers: int = 0
+        # Track whether flush has been invoked so it can only happen once
+        self._flushed = False
+
+    def __aiter__(self) -> AsyncIterator[T]:
+        return self
+
+    async def __anext__(self) -> T:
+        if self.done():
+            raise StopAsyncIteration
+        self._waiting_recievers += 1
+        try:
+            result = await self._queue.get()
+            if result is self.__flush:
+                raise StopAsyncIteration
+            return result
+        finally:
+            self._waiting_recievers -= 1
+            self._queue.task_done()
+
+    def closed(self) -> bool:
+        """
+        Returns True if this channel is closed and no-longer accepting new items
+        """
+        return self._closed
+
+    def done(self) -> bool:
+        """
+        Check if this channel is done.
+
+        :return: True if this channel is closed and and has been drained of items in
+        which case any further attempts to recieve an item from this channel will raise
+        a ChannelDone exception.
+        """
+        # After close the channel is not yet done until there is at least one waiting
+        # reciever per enqueued item.
+        return self._closed and self._queue.qsize() <= self._waiting_recievers
+
+    async def send_from(
+        self, source: Union[Iterable[T], AsyncIterable[T]], close: bool = False
+    ) -> "AsyncChannel[T]":
+        """
+        Iterates the given [Async]Iterable and sends all the resulting items.
+        If close is set to True then subsequent send calls will be rejected with a
+        ChannelClosed exception.
+        :param source: an iterable of items to send
+        :param close:
+            if True then the channel will be closed after the source has been exhausted
+
+        """
+        if self._closed:
+            raise ChannelClosed("Cannot send through a closed channel")
+        if isinstance(source, AsyncIterable):
+            async for item in source:
+                await self._queue.put(item)
+        else:
+            for item in source:
+                await self._queue.put(item)
+        if close:
+            # Complete the closing process
+            self.close()
+        return self
+
+    async def send(self, item: T) -> "AsyncChannel[T]":
+        """
+        Send a single item over this channel.
+        :param item: The item to send
+        """
+        if self._closed:
+            raise ChannelClosed("Cannot send through a closed channel")
+        await self._queue.put(item)
+        return self
+
+    async def recieve(self) -> Optional[T]:
+        """
+        Returns the next item from this channel when it becomes available,
+        or None if the channel is closed before another item is sent.
+        :return: An item from the channel
+        """
+        if self.done():
+            raise ChannelDone("Cannot recieve from a closed channel")
+        self._waiting_recievers += 1
+        try:
+            result = await self._queue.get()
+            if result is self.__flush:
+                return None
+            return result
+        finally:
+            self._waiting_recievers -= 1
+            self._queue.task_done()
+
+    def close(self):
+        """
+        Close this channel to new items
+        """
+        self._closed = True
+        asyncio.ensure_future(self._flush_queue())
+
+    async def _flush_queue(self):
+        """
+        To be called after the channel is closed. Pushes a number of self.__flush
+        objects to the queue to ensure no waiting consumers get deadlocked.
+        """
+        if not self._flushed:
+            self._flushed = True
+            deadlocked_recievers = max(0, self._waiting_recievers - self._queue.qsize())
+            for _ in range(deadlocked_recievers):
+                await self._queue.put(self.__flush)
+
+    # A special signal object for flushing the queue when the channel is closed
+    __flush = object()

betterproto/plugin.py

@@ -6,10 +6,10 @@ import re
 import stringcase
 import sys
 import textwrap
-from typing import List
+from typing import List, Union
+import betterproto
 from betterproto.casing import safe_snake_case
 from betterproto.compile.importing import get_ref_type
-import betterproto
 
 try:
     # betterproto[compiler] specific dependencies
@@ -58,8 +58,8 @@ def py_type(
         raise NotImplementedError(f"Unknown type {descriptor.type}")
 
 
-def get_py_zero(type_num: int) -> str:
+def get_py_zero(type_num: int) -> Union[str, float]:
-    zero = 0
+    zero: Union[str, float] = 0
     if type_num in []:
         zero = 0.0
     elif type_num == 8:
@@ -311,9 +311,6 @@ def generate_code(request, response):
                 }
 
                 for j, method in enumerate(service.method):
-                    if method.client_streaming:
-                        raise NotImplementedError("Client streaming not yet supported")
-
                     input_message = None
                     input_type = get_ref_type(
                         package, output["imports"], method.input_type
@@ -347,8 +344,12 @@ def generate_code(request, response):
                         }
                     )
 
+                    if method.client_streaming:
+                        output["typing_imports"].add("AsyncIterable")
+                        output["typing_imports"].add("Iterable")
+                        output["typing_imports"].add("Union")
                     if method.server_streaming:
-                        output["typing_imports"].add("AsyncGenerator")
+                        output["typing_imports"].add("AsyncIterator")
 
                 output["services"].append(data)
 

betterproto/templates/template.py.j2

@@ -63,11 +63,28 @@ class {{ service.py_name }}Stub(betterproto.ServiceStub):
 
     {% endif %}
     {% for method in service.methods %}
-    async def {{ method.py_name }}(self{% if method.input_message and method.input_message.properties %}, *, {% for field in method.input_message.properties %}{{ field.py_name }}: {% if field.zero == "None" and not field.type.startswith("Optional[") %}Optional[{{ field.type }}]{% else %}{{ field.type }}{% endif %} = {{ field.zero }}{% if not loop.last %}, {% endif %}{% endfor %}{% endif %}) -> {% if method.server_streaming %}AsyncGenerator[{{ method.output }}, None]{% else %}{{ method.output }}{% endif %}:
+    async def {{ method.py_name }}(self
+        {%- if not method.client_streaming -%}
+            {%- if method.input_message and method.input_message.properties -%}, *,
+                {%- for field in method.input_message.properties -%}
+                    {{ field.py_name }}: {% if field.zero == "None" and not field.type.startswith("Optional[") -%}
+                                            Optional[{{ field.type }}]
+                                         {%- else -%}
+                                            {{ field.type }}
+                                         {%- endif -%} = {{ field.zero }}
+                    {%- if not loop.last %}, {% endif -%}
+                {%- endfor -%}
+            {%- endif -%}
+        {%- else -%}
+            {# Client streaming: need a request iterator instead #}
+            , request_iterator: Union[AsyncIterable["{{ method.input }}"], Iterable["{{ method.input }}"]]
+        {%- endif -%}
+            ) -> {% if method.server_streaming %}AsyncIterator[{{ method.output }}]{% else %}{{ method.output }}{% endif %}:
         {% if method.comment %}
 {{ method.comment }}
 
         {% endif %}
+        {% if not method.client_streaming %}
         request = {{ method.input }}()
         {% for field in method.input_message.properties %}
             {% if field.field_type == 'message' %}
@@ -77,20 +94,41 @@ class {{ service.py_name }}Stub(betterproto.ServiceStub):
         request.{{ field.py_name }} = {{ field.py_name }}
             {% endif %}
         {% endfor %}
+        {% endif %}
 
         {% if method.server_streaming %}
+            {% if method.client_streaming %}
+        async for response in self._stream_stream(
+            "{{ method.route }}",
+            request_iterator,
+            {{ method.input }},
+            {{ method.output }},
+        ):
+            yield response
+            {% else %}{# i.e. not client streaming #}
         async for response in self._unary_stream(
             "{{ method.route }}",
             request,
             {{ method.output }},
         ):
             yield response
-        {% else %}
+
+            {% endif %}{# if client streaming #}
+        {% else %}{# i.e. not server streaming #}
+            {% if method.client_streaming %}
+        return await self._stream_unary(
+            "{{ method.route }}",
+            request_iterator,
+            {{ method.input }},
+            {{ method.output }}
+        )
+            {% else %}{# i.e. not client streaming #}
         return await self._unary_unary(
             "{{ method.route }}",
             request,
-            {{ method.output }},
+            {{ method.output }}
         )
+            {% endif %}{# client streaming #}
         {% endif %}
 
     {% endfor %}

betterproto/tests/generate.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python
-import glob
+import asyncio
 import os
+from pathlib import Path
 import shutil
 import subprocess
 import sys
@@ -20,58 +21,63 @@ from betterproto.tests.util import (
 os.environ["PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION"] = "python"
 
 
-def clear_directory(path: str):
+def clear_directory(dir_path: Path):
-    for file_or_directory in glob.glob(os.path.join(path, "*")):
+    for file_or_directory in dir_path.glob("*"):
-        if os.path.isdir(file_or_directory):
+        if file_or_directory.is_dir():
             shutil.rmtree(file_or_directory)
         else:
-            os.remove(file_or_directory)
+            file_or_directory.unlink()
 
 
-def generate(whitelist: Set[str]):
+async def generate(whitelist: Set[str], verbose: bool):
-    path_whitelist = {os.path.realpath(e) for e in whitelist if os.path.exists(e)}
+    test_case_names = set(get_directories(inputs_path)) - {"__pycache__"}
-    name_whitelist = {e for e in whitelist if not os.path.exists(e)}
 
-    test_case_names = set(get_directories(inputs_path))
+    path_whitelist = set()
-
+    name_whitelist = set()
-    failed_test_cases = []
+    for item in whitelist:
+        if item in test_case_names:
+            name_whitelist.add(item)
+            continue
+        path_whitelist.add(item)
 
+    generation_tasks = []
     for test_case_name in sorted(test_case_names):
-        test_case_input_path = os.path.realpath(
+        test_case_input_path = inputs_path.joinpath(test_case_name).resolve()
-            os.path.join(inputs_path, test_case_name)
-        )
-
         if (
             whitelist
-            and test_case_input_path not in path_whitelist
+            and str(test_case_input_path) not in path_whitelist
             and test_case_name not in name_whitelist
         ):
             continue
+        generation_tasks.append(
+            generate_test_case_output(test_case_input_path, test_case_name, verbose)
+        )
 
-        print(f"Generating output for {test_case_name}")
+    failed_test_cases = []
-        try:
+    # Wait for all subprocs and match any failures to names to report
-            generate_test_case_output(test_case_name, test_case_input_path)
+    for test_case_name, result in zip(
-        except subprocess.CalledProcessError as e:
+        sorted(test_case_names), await asyncio.gather(*generation_tasks)
+    ):
+        if result != 0:
             failed_test_cases.append(test_case_name)
 
     if failed_test_cases:
-        sys.stderr.write("\nFailed to generate the following test cases:\n")
+        sys.stderr.write(
+            "\n\033[31;1;4mFailed to generate the following test cases:\033[0m\n"
+        )
         for failed_test_case in failed_test_cases:
             sys.stderr.write(f"- {failed_test_case}\n")
 
 
-def generate_test_case_output(test_case_name, test_case_input_path=None):
+async def generate_test_case_output(
-    if not test_case_input_path:
+    test_case_input_path: Path, test_case_name: str, verbose: bool
-        test_case_input_path = os.path.realpath(
+) -> int:
-            os.path.join(inputs_path, test_case_name)
+    """
-        )
+    Returns the max of the subprocess return values
+    """
 
-    test_case_output_path_reference = os.path.join(
+    test_case_output_path_reference = output_path_reference.joinpath(test_case_name)
-        output_path_reference, test_case_name
+    test_case_output_path_betterproto = output_path_betterproto.joinpath(test_case_name)
-    )
-    test_case_output_path_betterproto = os.path.join(
-        output_path_betterproto, test_case_name
-    )
 
     os.makedirs(test_case_output_path_reference, exist_ok=True)
     os.makedirs(test_case_output_path_betterproto, exist_ok=True)
@@ -79,14 +85,36 @@ def generate_test_case_output(test_case_name, test_case_input_path=None):
     clear_directory(test_case_output_path_reference)
     clear_directory(test_case_output_path_betterproto)
 
-    protoc_reference(test_case_input_path, test_case_output_path_reference)
+    (
-    protoc_plugin(test_case_input_path, test_case_output_path_betterproto)
+        (ref_out, ref_err, ref_code),
+        (plg_out, plg_err, plg_code),
+    ) = await asyncio.gather(
+        protoc_reference(test_case_input_path, test_case_output_path_reference),
+        protoc_plugin(test_case_input_path, test_case_output_path_betterproto),
+    )
+
+    message = f"Generated output for {test_case_name!r}"
+    if verbose:
+        print(f"\033[31;1;4m{message}\033[0m")
+        if ref_out:
+            sys.stdout.buffer.write(ref_out)
+        if ref_err:
+            sys.stderr.buffer.write(ref_err)
+        if plg_out:
+            sys.stdout.buffer.write(plg_out)
+        if plg_err:
+            sys.stderr.buffer.write(plg_err)
+        sys.stdout.buffer.flush()
+        sys.stderr.buffer.flush()
+    else:
+        print(message)
+
+    return max(ref_code, plg_code)
 
 
 HELP = "\n".join(
-    [
+    (
-        "Usage: python generate.py",
+        "Usage: python generate.py [-h] [-v] [DIRECTORIES or NAMES]",
-        "       python generate.py [DIRECTORIES or NAMES]",
         "Generate python classes for standard tests.",
         "",
         "DIRECTORIES    One or more relative or absolute directories of test-cases to generate classes for.",
@@ -94,7 +122,7 @@ HELP = "\n".join(
         "",
         "NAMES          One or more test-case names to generate classes for.",
         "               python generate.py bool double enums",
-    ]
+    )
 )
 
 
@@ -102,9 +130,13 @@ def main():
     if set(sys.argv).intersection({"-h", "--help"}):
         print(HELP)
         return
-    whitelist = set(sys.argv[1:])
+    if sys.argv[1:2] == ["-v"]:
-
+        verbose = True
-    generate(whitelist)
+        whitelist = set(sys.argv[2:])
+    else:
+        verbose = False
+        whitelist = set(sys.argv[1:])
+    asyncio.get_event_loop().run_until_complete(generate(whitelist, verbose))
 
 
 if __name__ == "__main__":

betterproto/tests/grpc/test_grpclib_client.py

@@ -0,0 +1,154 @@
+import asyncio
+from betterproto.tests.output_betterproto.service.service import (
+    DoThingResponse,
+    DoThingRequest,
+    GetThingRequest,
+    GetThingResponse,
+    TestStub as ThingServiceClient,
+)
+import grpclib
+from grpclib.testing import ChannelFor
+import pytest
+from betterproto.grpc.util.async_channel import AsyncChannel
+from .thing_service import ThingService
+
+
+async def _test_client(client, name="clean room", **kwargs):
+    response = await client.do_thing(name=name)
+    assert response.names == [name]
+
+
+def _assert_request_meta_recieved(deadline, metadata):
+    def server_side_test(stream):
+        assert stream.deadline._timestamp == pytest.approx(
+            deadline._timestamp, 1
+        ), "The provided deadline should be recieved serverside"
+        assert (
+            stream.metadata["authorization"] == metadata["authorization"]
+        ), "The provided authorization metadata should be recieved serverside"
+
+    return server_side_test
+
+
+@pytest.mark.asyncio
+async def test_simple_service_call():
+    async with ChannelFor([ThingService()]) as channel:
+        await _test_client(ThingServiceClient(channel))
+
+
+@pytest.mark.asyncio
+async def test_service_call_with_upfront_request_params():
+    # Setting deadline
+    deadline = grpclib.metadata.Deadline.from_timeout(22)
+    metadata = {"authorization": "12345"}
+    async with ChannelFor(
+        [ThingService(test_hook=_assert_request_meta_recieved(deadline, metadata),)]
+    ) as channel:
+        await _test_client(
+            ThingServiceClient(channel, deadline=deadline, metadata=metadata)
+        )
+
+    # Setting timeout
+    timeout = 99
+    deadline = grpclib.metadata.Deadline.from_timeout(timeout)
+    metadata = {"authorization": "12345"}
+    async with ChannelFor(
+        [ThingService(test_hook=_assert_request_meta_recieved(deadline, metadata),)]
+    ) as channel:
+        await _test_client(
+            ThingServiceClient(channel, timeout=timeout, metadata=metadata)
+        )
+
+
+@pytest.mark.asyncio
+async def test_service_call_lower_level_with_overrides():
+    THING_TO_DO = "get milk"
+
+    # Setting deadline
+    deadline = grpclib.metadata.Deadline.from_timeout(22)
+    metadata = {"authorization": "12345"}
+    kwarg_deadline = grpclib.metadata.Deadline.from_timeout(28)
+    kwarg_metadata = {"authorization": "12345"}
+    async with ChannelFor(
+        [ThingService(test_hook=_assert_request_meta_recieved(deadline, metadata),)]
+    ) as channel:
+        client = ThingServiceClient(channel, deadline=deadline, metadata=metadata)
+        response = await client._unary_unary(
+            "/service.Test/DoThing",
+            DoThingRequest(THING_TO_DO),
+            DoThingResponse,
+            deadline=kwarg_deadline,
+            metadata=kwarg_metadata,
+        )
+        assert response.names == [THING_TO_DO]
+
+    # Setting timeout
+    timeout = 99
+    deadline = grpclib.metadata.Deadline.from_timeout(timeout)
+    metadata = {"authorization": "12345"}
+    kwarg_timeout = 9000
+    kwarg_deadline = grpclib.metadata.Deadline.from_timeout(kwarg_timeout)
+    kwarg_metadata = {"authorization": "09876"}
+    async with ChannelFor(
+        [
+            ThingService(
+                test_hook=_assert_request_meta_recieved(kwarg_deadline, kwarg_metadata),
+            )
+        ]
+    ) as channel:
+        client = ThingServiceClient(channel, deadline=deadline, metadata=metadata)
+        response = await client._unary_unary(
+            "/service.Test/DoThing",
+            DoThingRequest(THING_TO_DO),
+            DoThingResponse,
+            timeout=kwarg_timeout,
+            metadata=kwarg_metadata,
+        )
+        assert response.names == [THING_TO_DO]
+
+
+@pytest.mark.asyncio
+async def test_async_gen_for_unary_stream_request():
+    thing_name = "my milkshakes"
+
+    async with ChannelFor([ThingService()]) as channel:
+        client = ThingServiceClient(channel)
+        expected_versions = [5, 4, 3, 2, 1]
+        async for response in client.get_thing_versions(name=thing_name):
+            assert response.name == thing_name
+            assert response.version == expected_versions.pop()
+
+
+@pytest.mark.asyncio
+async def test_async_gen_for_stream_stream_request():
+    some_things = ["cake", "cricket", "coral reef"]
+    more_things = ["ball", "that", "56kmodem", "liberal humanism", "cheesesticks"]
+    expected_things = (*some_things, *more_things)
+
+    async with ChannelFor([ThingService()]) as channel:
+        client = ThingServiceClient(channel)
+        # Use an AsyncChannel to decouple sending and recieving, it'll send some_things
+        # immediately and we'll use it to send more_things later, after recieving some
+        # results
+        request_chan = AsyncChannel()
+        send_initial_requests = asyncio.ensure_future(
+            request_chan.send_from(GetThingRequest(name) for name in some_things)
+        )
+        response_index = 0
+        async for response in client.get_different_things(request_chan):
+            assert response.name == expected_things[response_index]
+            assert response.version == response_index + 1
+            response_index += 1
+            if more_things:
+                # Send some more requests as we recieve reponses to be sure coordination of
+                # send/recieve events doesn't matter
+                await request_chan.send(GetThingRequest(more_things.pop(0)))
+            elif not send_initial_requests.done():
+                # Make sure the sending task it completed
+                await send_initial_requests
+            else:
+                # No more things to send make sure channel is closed
+                request_chan.close()
+        assert response_index == len(
+            expected_things
+        ), "Didn't recieve all exptected responses"

betterproto/tests/grpc/test_stream_stream.py

@@ -0,0 +1,100 @@
+import asyncio
+import betterproto
+from betterproto.grpc.util.async_channel import AsyncChannel
+from dataclasses import dataclass
+import pytest
+from typing import AsyncIterator
+
+
+@dataclass
+class Message(betterproto.Message):
+    body: str = betterproto.string_field(1)
+
+
+@pytest.fixture
+def expected_responses():
+    return [Message("Hello world 1"), Message("Hello world 2"), Message("Done")]
+
+
+class ClientStub:
+    async def connect(self, requests: AsyncIterator):
+        await asyncio.sleep(0.1)
+        async for request in requests:
+            await asyncio.sleep(0.1)
+            yield request
+        await asyncio.sleep(0.1)
+        yield Message("Done")
+
+
+async def to_list(generator: AsyncIterator):
+    result = []
+    async for value in generator:
+        result.append(value)
+    return result
+
+
+@pytest.fixture
+def client():
+    # channel = Channel(host='127.0.0.1', port=50051)
+    # return ClientStub(channel)
+    return ClientStub()
+
+
+@pytest.mark.asyncio
+async def test_send_from_before_connect_and_close_automatically(
+    client, expected_responses
+):
+    requests = AsyncChannel()
+    await requests.send_from(
+        [Message(body="Hello world 1"), Message(body="Hello world 2")], close=True
+    )
+    responses = client.connect(requests)
+
+    assert await to_list(responses) == expected_responses
+
+
+@pytest.mark.asyncio
+async def test_send_from_after_connect_and_close_automatically(
+    client, expected_responses
+):
+    requests = AsyncChannel()
+    responses = client.connect(requests)
+    await requests.send_from(
+        [Message(body="Hello world 1"), Message(body="Hello world 2")], close=True
+    )
+
+    assert await to_list(responses) == expected_responses
+
+
+@pytest.mark.asyncio
+async def test_send_from_close_manually_immediately(client, expected_responses):
+    requests = AsyncChannel()
+    responses = client.connect(requests)
+    await requests.send_from(
+        [Message(body="Hello world 1"), Message(body="Hello world 2")], close=False
+    )
+    requests.close()
+
+    assert await to_list(responses) == expected_responses
+
+
+@pytest.mark.asyncio
+async def test_send_individually_and_close_before_connect(client, expected_responses):
+    requests = AsyncChannel()
+    await requests.send(Message(body="Hello world 1"))
+    await requests.send(Message(body="Hello world 2"))
+    requests.close()
+    responses = client.connect(requests)
+
+    assert await to_list(responses) == expected_responses
+
+
+@pytest.mark.asyncio
+async def test_send_individually_and_close_after_connect(client, expected_responses):
+    requests = AsyncChannel()
+    await requests.send(Message(body="Hello world 1"))
+    await requests.send(Message(body="Hello world 2"))
+    responses = client.connect(requests)
+    requests.close()
+
+    assert await to_list(responses) == expected_responses

betterproto/tests/grpc/thing_service.py

@@ -0,0 +1,83 @@
+from betterproto.tests.output_betterproto.service.service import (
+    DoThingResponse,
+    DoThingRequest,
+    GetThingRequest,
+    GetThingResponse,
+    TestStub as ThingServiceClient,
+)
+import grpclib
+from typing import Any, Dict
+
+
+class ThingService:
+    def __init__(self, test_hook=None):
+        # This lets us pass assertions to the servicer ;)
+        self.test_hook = test_hook
+
+    async def do_thing(
+        self, stream: "grpclib.server.Stream[DoThingRequest, DoThingResponse]"
+    ):
+        request = await stream.recv_message()
+        if self.test_hook is not None:
+            self.test_hook(stream)
+        await stream.send_message(DoThingResponse([request.name]))
+
+    async def do_many_things(
+        self, stream: "grpclib.server.Stream[DoThingRequest, DoThingResponse]"
+    ):
+        thing_names = [request.name for request in stream]
+        if self.test_hook is not None:
+            self.test_hook(stream)
+        await stream.send_message(DoThingResponse(thing_names))
+
+    async def get_thing_versions(
+        self, stream: "grpclib.server.Stream[GetThingRequest, GetThingResponse]"
+    ):
+        request = await stream.recv_message()
+        if self.test_hook is not None:
+            self.test_hook(stream)
+        for version_num in range(1, 6):
+            await stream.send_message(
+                GetThingResponse(name=request.name, version=version_num)
+            )
+
+    async def get_different_things(
+        self, stream: "grpclib.server.Stream[GetThingRequest, GetThingResponse]"
+    ):
+        if self.test_hook is not None:
+            self.test_hook(stream)
+        #  Respond to each input item immediately
+        response_num = 0
+        async for request in stream:
+            response_num += 1
+            await stream.send_message(
+                GetThingResponse(name=request.name, version=response_num)
+            )
+
+    def __mapping__(self) -> Dict[str, "grpclib.const.Handler"]:
+        return {
+            "/service.Test/DoThing": grpclib.const.Handler(
+                self.do_thing,
+                grpclib.const.Cardinality.UNARY_UNARY,
+                DoThingRequest,
+                DoThingResponse,
+            ),
+            "/service.Test/DoManyThings": grpclib.const.Handler(
+                self.do_many_things,
+                grpclib.const.Cardinality.STREAM_UNARY,
+                DoThingRequest,
+                DoThingResponse,
+            ),
+            "/service.Test/GetThingVersions": grpclib.const.Handler(
+                self.get_thing_versions,
+                grpclib.const.Cardinality.UNARY_STREAM,
+                GetThingRequest,
+                GetThingResponse,
+            ),
+            "/service.Test/GetDifferentThings": grpclib.const.Handler(
+                self.get_different_things,
+                grpclib.const.Cardinality.STREAM_STREAM,
+                GetThingRequest,
+                GetThingResponse,
+            ),
+        }

betterproto/tests/inputs/googletypes_response/test_googletypes_response.py

@@ -23,7 +23,7 @@ test_cases = [
 
 @pytest.mark.asyncio
 @pytest.mark.parametrize(["service_method", "wrapper_class", "value"], test_cases)
-async def test_channel_receives_wrapped_type(
+async def test_channel_recieves_wrapped_type(
     service_method: Callable[[TestStub], Any], wrapper_class: Callable, value
 ):
     wrapped_value = wrapper_class()

betterproto/tests/inputs/service/service.proto

@@ -3,13 +3,25 @@ syntax = "proto3";
 package service;
 
 message DoThingRequest {
-  int32 iterations = 1;
+  string name = 1;
 }
 
 message DoThingResponse {
-  int32 successfulIterations = 1;
+  repeated string names = 1;
+}
+
+message GetThingRequest {
+  string name = 1;
+}
+
+message GetThingResponse {
+  string name = 1;
+  int32 version = 2;
 }
 
 service Test {
   rpc DoThing (DoThingRequest) returns (DoThingResponse);
+  rpc DoManyThings (stream DoThingRequest) returns (DoThingResponse);
+  rpc GetThingVersions (GetThingRequest) returns (stream GetThingResponse);
+  rpc GetDifferentThings (stream GetThingRequest) returns (stream GetThingResponse);
 }

betterproto/tests/inputs/service/test_service.py

@@ -1,132 +0,0 @@
-import betterproto
-import grpclib
-from grpclib.testing import ChannelFor
-import pytest
-from typing import Dict
-
-from betterproto.tests.output_betterproto.service.service import (
-    DoThingResponse,
-    DoThingRequest,
-    TestStub as ExampleServiceStub,
-)
-
-
-class ExampleService:
-    def __init__(self, test_hook=None):
-        # This lets us pass assertions to the servicer ;)
-        self.test_hook = test_hook
-
-    async def DoThing(
-        self, stream: "grpclib.server.Stream[DoThingRequest, DoThingResponse]"
-    ):
-        request = await stream.recv_message()
-        print("self.test_hook", self.test_hook)
-        if self.test_hook is not None:
-            self.test_hook(stream)
-        for iteration in range(request.iterations):
-            pass
-        await stream.send_message(DoThingResponse(request.iterations))
-
-    def __mapping__(self) -> Dict[str, grpclib.const.Handler]:
-        return {
-            "/service.Test/DoThing": grpclib.const.Handler(
-                self.DoThing,
-                grpclib.const.Cardinality.UNARY_UNARY,
-                DoThingRequest,
-                DoThingResponse,
-            )
-        }
-
-
-async def _test_stub(stub, iterations=42, **kwargs):
-    response = await stub.do_thing(iterations=iterations)
-    assert response.successful_iterations == iterations
-
-
-def _get_server_side_test(deadline, metadata):
-    def server_side_test(stream):
-        assert stream.deadline._timestamp == pytest.approx(
-            deadline._timestamp, 1
-        ), "The provided deadline should be recieved serverside"
-        assert (
-            stream.metadata["authorization"] == metadata["authorization"]
-        ), "The provided authorization metadata should be recieved serverside"
-
-    return server_side_test
-
-
-@pytest.mark.asyncio
-async def test_simple_service_call():
-    async with ChannelFor([ExampleService()]) as channel:
-        await _test_stub(ExampleServiceStub(channel))
-
-
-@pytest.mark.asyncio
-async def test_service_call_with_upfront_request_params():
-    # Setting deadline
-    deadline = grpclib.metadata.Deadline.from_timeout(22)
-    metadata = {"authorization": "12345"}
-    async with ChannelFor(
-        [ExampleService(test_hook=_get_server_side_test(deadline, metadata))]
-    ) as channel:
-        await _test_stub(
-            ExampleServiceStub(channel, deadline=deadline, metadata=metadata)
-        )
-
-    # Setting timeout
-    timeout = 99
-    deadline = grpclib.metadata.Deadline.from_timeout(timeout)
-    metadata = {"authorization": "12345"}
-    async with ChannelFor(
-        [ExampleService(test_hook=_get_server_side_test(deadline, metadata))]
-    ) as channel:
-        await _test_stub(
-            ExampleServiceStub(channel, timeout=timeout, metadata=metadata)
-        )
-
-
-@pytest.mark.asyncio
-async def test_service_call_lower_level_with_overrides():
-    ITERATIONS = 99
-
-    # Setting deadline
-    deadline = grpclib.metadata.Deadline.from_timeout(22)
-    metadata = {"authorization": "12345"}
-    kwarg_deadline = grpclib.metadata.Deadline.from_timeout(28)
-    kwarg_metadata = {"authorization": "12345"}
-    async with ChannelFor(
-        [ExampleService(test_hook=_get_server_side_test(deadline, metadata))]
-    ) as channel:
-        stub = ExampleServiceStub(channel, deadline=deadline, metadata=metadata)
-        response = await stub._unary_unary(
-            "/service.Test/DoThing",
-            DoThingRequest(ITERATIONS),
-            DoThingResponse,
-            deadline=kwarg_deadline,
-            metadata=kwarg_metadata,
-        )
-        assert response.successful_iterations == ITERATIONS
-
-    # Setting timeout
-    timeout = 99
-    deadline = grpclib.metadata.Deadline.from_timeout(timeout)
-    metadata = {"authorization": "12345"}
-    kwarg_timeout = 9000
-    kwarg_deadline = grpclib.metadata.Deadline.from_timeout(kwarg_timeout)
-    kwarg_metadata = {"authorization": "09876"}
-    async with ChannelFor(
-        [
-            ExampleService(
-                test_hook=_get_server_side_test(kwarg_deadline, kwarg_metadata)
-            )
-        ]
-    ) as channel:
-        stub = ExampleServiceStub(channel, deadline=deadline, metadata=metadata)
-        response = await stub._unary_unary(
-            "/service.Test/DoThing",
-            DoThingRequest(ITERATIONS),
-            DoThingResponse,
-            timeout=kwarg_timeout,
-            metadata=kwarg_metadata,
-        )
-        assert response.successful_iterations == ITERATIONS

betterproto/tests/test_inputs.py

@@ -23,7 +23,7 @@ from google.protobuf.json_format import Parse
 
 class TestCases:
     def __init__(self, path, services: Set[str], xfail: Set[str]):
-        _all = set(get_directories(path))
+        _all = set(get_directories(path)) - {"__pycache__"}
         _services = services
         _messages = (_all - services) - {"__pycache__"}
         _messages_with_json = {

betterproto/tests/util.py

@@ -1,23 +1,24 @@
+import asyncio
 import os
-import subprocess
+from pathlib import Path
-from typing import Generator
+from typing import Generator, IO, Optional
 
 os.environ["PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION"] = "python"
 
-root_path = os.path.dirname(os.path.realpath(__file__))
+root_path = Path(__file__).resolve().parent
-inputs_path = os.path.join(root_path, "inputs")
+inputs_path = root_path.joinpath("inputs")
-output_path_reference = os.path.join(root_path, "output_reference")
+output_path_reference = root_path.joinpath("output_reference")
-output_path_betterproto = os.path.join(root_path, "output_betterproto")
+output_path_betterproto = root_path.joinpath("output_betterproto")
 
 if os.name == "nt":
-    plugin_path = os.path.join(root_path, "..", "plugin.bat")
+    plugin_path = root_path.joinpath("..", "plugin.bat").resolve()
 else:
-    plugin_path = os.path.join(root_path, "..", "plugin.py")
+    plugin_path = root_path.joinpath("..", "plugin.py").resolve()
 
 
-def get_files(path, end: str) -> Generator[str, None, None]:
+def get_files(path, suffix: str) -> Generator[str, None, None]:
     for r, dirs, files in os.walk(path):
-        for filename in [f for f in files if f.endswith(end)]:
+        for filename in [f for f in files if f.endswith(suffix)]:
             yield os.path.join(r, filename)
 
 
@@ -27,36 +28,30 @@ def get_directories(path):
             yield directory
 
 
-def relative(file: str, path: str):
+async def protoc_plugin(path: str, output_dir: str):
-    return os.path.join(os.path.dirname(file), path)
+    proc = await asyncio.create_subprocess_shell(
-
-
-def read_relative(file: str, path: str):
-    with open(relative(file, path)) as fh:
-        return fh.read()
-
-
-def protoc_plugin(path: str, output_dir: str) -> subprocess.CompletedProcess:
-    return subprocess.run(
         f"protoc --plugin=protoc-gen-custom={plugin_path} --custom_out={output_dir} --proto_path={path} {path}/*.proto",
-        shell=True,
+        stdout=asyncio.subprocess.PIPE,
-        check=True,
+        stderr=asyncio.subprocess.PIPE,
     )
+    return (*(await proc.communicate()), proc.returncode)
 
 
-def protoc_reference(path: str, output_dir: str):
+async def protoc_reference(path: str, output_dir: str):
-    subprocess.run(
+    proc = await asyncio.create_subprocess_shell(
         f"protoc --python_out={output_dir} --proto_path={path} {path}/*.proto",
-        shell=True,
+        stdout=asyncio.subprocess.PIPE,
+        stderr=asyncio.subprocess.PIPE,
     )
+    return (*(await proc.communicate()), proc.returncode)
 
 
-def get_test_case_json_data(test_case_name, json_file_name=None):
+def get_test_case_json_data(test_case_name: str, json_file_name: Optional[str] = None):
     test_data_file_name = json_file_name if json_file_name else f"{test_case_name}.json"
-    test_data_file_path = os.path.join(inputs_path, test_case_name, test_data_file_name)
+    test_data_file_path = inputs_path.joinpath(test_case_name, test_data_file_name)
 
-    if not os.path.exists(test_data_file_path):
+    if not test_data_file_path.exists():
         return None
 
-    with open(test_data_file_path) as fh:
+    with test_data_file_path.open("r") as fh:
         return fh.read()