[Python Example] Fix compression example (#34745)

Fix: https://github.com/grpc/grpc/issues/34690

Also added generated proto files to example folder so we can run example
directly.
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examples/python/Makefile

@@ -80,6 +80,10 @@ ARTIFACTS += lb_policies/helloworld_pb2.py
 ARTIFACTS += lb_policies/helloworld_pb2_grpc.py
 ARTIFACTS += lb_policies/helloworld_pb2.pyi
 
+ARTIFACTS += compression/helloworld_pb2.py
+ARTIFACTS += compression/helloworld_pb2_grpc.py
+ARTIFACTS += compression/helloworld_pb2.pyi
+
 .PHONY: all
 all: ${ARTIFACTS}
 
@@ -132,6 +136,9 @@ data_transmission/demo_pb2.py data_transmission/demo_pb2_grpc.py data_transmissi
 lb_policies/helloworld_pb2.py lb_policies/helloworld_pb2_grpc.py lb_policies/helloworld_pb2.pyi: ../protos/helloworld.proto
 	python3 -m grpc_tools.protoc --python_out=lb_policies --grpc_python_out=lb_policies --pyi_out=lb_policies -I ../protos ../protos/helloworld.proto
 
+compression/helloworld_pb2.py compression/helloworld_pb2_grpc.py compression/helloworld_pb2.pyi: ../protos/helloworld.proto
+	python3 -m grpc_tools.protoc --python_out=compression --grpc_python_out=compression --pyi_out=compression -I ../protos ../protos/helloworld.proto
+
 .PHONY: clean
 clean:
 	rm -f ${ARTIFACTS}

examples/python/compression/README.md

@@ -50,7 +50,7 @@ server = grpc.server(futures.ThreadPoolExecutor(),
 
 ```python
 def SayHello(self, request, context):
-    context.set_response_compression(grpc.Compression.NoCompression)
+    context.set_compression(grpc.Compression.NoCompression)
     return helloworld_pb2.HelloReply(message='Hello, %s!' % request.name)
 ```
 

examples/python/compression/client.py

@@ -21,9 +21,8 @@ import argparse
 import logging
 
 import grpc
-
-from examples.protos import helloworld_pb2
-from examples.protos import helloworld_pb2_grpc
+import helloworld_pb2
+import helloworld_pb2_grpc
 
 _DESCRIPTION = "A client capable of compression."
 _COMPRESSION_OPTIONS = {
@@ -33,6 +32,7 @@ _COMPRESSION_OPTIONS = {
 }
 
 _LOGGER = logging.getLogger(__name__)
+_RPC_COUNT = 10
 
 
 def run_client(channel_compression, call_compression, target):
@@ -40,12 +40,13 @@ def run_client(channel_compression, call_compression, target):
         target, compression=channel_compression
     ) as channel:
         stub = helloworld_pb2_grpc.GreeterStub(channel)
-        response = stub.SayHello(
-            helloworld_pb2.HelloRequest(name="you"),
-            compression=call_compression,
-            wait_for_ready=True,
-        )
-        print("Response: {}".format(response))
+        for _ in range(_RPC_COUNT):
+            response = stub.SayHello(
+                helloworld_pb2.HelloRequest(name="you"),
+                compression=call_compression,
+                wait_for_ready=True,
+            )
+            print("Response: {}".format(response))
 
 
 def main():

examples/python/compression/helloworld_pb2.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: helloworld.proto
+"""Generated protocol buffer code."""
+from google.protobuf.internal import builder as _builder
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import descriptor_pool as _descriptor_pool
+from google.protobuf import symbol_database as _symbol_database
+# @@protoc_insertion_point(imports)
+
+_sym_db = _symbol_database.Default()
+
+
+
+
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x10helloworld.proto\x12\nhelloworld\"\x1c\n\x0cHelloRequest\x12\x0c\n\x04name\x18\x01 \x01(\t\"\x1d\n\nHelloReply\x12\x0f\n\x07message\x18\x01 \x01(\t2I\n\x07Greeter\x12>\n\x08SayHello\x12\x18.helloworld.HelloRequest\x1a\x16.helloworld.HelloReply\"\x00\x42\x36\n\x1bio.grpc.examples.helloworldB\x0fHelloWorldProtoP\x01\xa2\x02\x03HLWb\x06proto3')
+
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'helloworld_pb2', globals())
+if _descriptor._USE_C_DESCRIPTORS == False:
+
+  DESCRIPTOR._options = None
+  DESCRIPTOR._serialized_options = b'\n\033io.grpc.examples.helloworldB\017HelloWorldProtoP\001\242\002\003HLW'
+  _HELLOREQUEST._serialized_start=32
+  _HELLOREQUEST._serialized_end=60
+  _HELLOREPLY._serialized_start=62
+  _HELLOREPLY._serialized_end=91
+  _GREETER._serialized_start=93
+  _GREETER._serialized_end=166
+# @@protoc_insertion_point(module_scope)

examples/python/compression/helloworld_pb2.pyi

@@ -0,0 +1,17 @@
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from typing import ClassVar as _ClassVar, Optional as _Optional
+
+DESCRIPTOR: _descriptor.FileDescriptor
+
+class HelloReply(_message.Message):
+    __slots__ = ["message"]
+    MESSAGE_FIELD_NUMBER: _ClassVar[int]
+    message: str
+    def __init__(self, message: _Optional[str] = ...) -> None: ...
+
+class HelloRequest(_message.Message):
+    __slots__ = ["name"]
+    NAME_FIELD_NUMBER: _ClassVar[int]
+    name: str
+    def __init__(self, name: _Optional[str] = ...) -> None: ...

examples/python/compression/helloworld_pb2_grpc.py

@@ -0,0 +1,70 @@
+# Generated by the gRPC Python protocol compiler plugin. DO NOT EDIT!
+"""Client and server classes corresponding to protobuf-defined services."""
+import grpc
+
+import helloworld_pb2 as helloworld__pb2
+
+
+class GreeterStub(object):
+    """The greeting service definition.
+    """
+
+    def __init__(self, channel):
+        """Constructor.
+
+        Args:
+            channel: A grpc.Channel.
+        """
+        self.SayHello = channel.unary_unary(
+                '/helloworld.Greeter/SayHello',
+                request_serializer=helloworld__pb2.HelloRequest.SerializeToString,
+                response_deserializer=helloworld__pb2.HelloReply.FromString,
+                )
+
+
+class GreeterServicer(object):
+    """The greeting service definition.
+    """
+
+    def SayHello(self, request, context):
+        """Sends a greeting
+        """
+        context.set_code(grpc.StatusCode.UNIMPLEMENTED)
+        context.set_details('Method not implemented!')
+        raise NotImplementedError('Method not implemented!')
+
+
+def add_GreeterServicer_to_server(servicer, server):
+    rpc_method_handlers = {
+            'SayHello': grpc.unary_unary_rpc_method_handler(
+                    servicer.SayHello,
+                    request_deserializer=helloworld__pb2.HelloRequest.FromString,
+                    response_serializer=helloworld__pb2.HelloReply.SerializeToString,
+            ),
+    }
+    generic_handler = grpc.method_handlers_generic_handler(
+            'helloworld.Greeter', rpc_method_handlers)
+    server.add_generic_rpc_handlers((generic_handler,))
+
+
+ # This class is part of an EXPERIMENTAL API.
+class Greeter(object):
+    """The greeting service definition.
+    """
+
+    @staticmethod
+    def SayHello(request,
+            target,
+            options=(),
+            channel_credentials=None,
+            call_credentials=None,
+            insecure=False,
+            compression=None,
+            wait_for_ready=None,
+            timeout=None,
+            metadata=None):
+        return grpc.experimental.unary_unary(request, target, '/helloworld.Greeter/SayHello',
+            helloworld__pb2.HelloRequest.SerializeToString,
+            helloworld__pb2.HelloReply.FromString,
+            options, channel_credentials,
+            insecure, call_credentials, compression, wait_for_ready, timeout, metadata)

examples/python/compression/server.py

@@ -23,9 +23,8 @@ import logging
 import threading
 
 import grpc
-
-from examples.protos import helloworld_pb2
-from examples.protos import helloworld_pb2_grpc
+import helloworld_pb2
+import helloworld_pb2_grpc
 
 _DESCRIPTION = "A server capable of compression."
 _COMPRESSION_OPTIONS = {
@@ -41,7 +40,7 @@ _SERVER_HOST = "localhost"
 class Greeter(helloworld_pb2_grpc.GreeterServicer):
     def __init__(self, no_compress_every_n):
         super(Greeter, self).__init__()
-        self._no_compress_every_n = 0
+        self._no_compress_every_n = no_compress_every_n
         self._request_counter = 0
         self._counter_lock = threading.RLock()
 
@@ -58,7 +57,7 @@ class Greeter(helloworld_pb2_grpc.GreeterServicer):
 
     def SayHello(self, request, context):
         if self._should_suppress_compression():
-            context.set_response_compression(grpc.Compression.NoCompression)
+            context.set_compression(grpc.Compression.NoCompression)
         return helloworld_pb2.HelloReply(message="Hello, %s!" % request.name)
 
 

examples/python/compression/test/compression_example_test.py

@@ -49,6 +49,8 @@ class CompressionExampleTest(unittest.TestCase):
                     str(test_port),
                     "--server_compression",
                     "gzip",
+                    "--no_compress_every_n",
+                    "3",
                 )
             )
             try: