COH-32930 - Add functionality for is_ready() method on both gRPC v0 and v1 implementations (#281)

* COH-32930 - Add functionality for is_ready() method on both gRPC v0 and v1 implementations

Author: dhirupandey

src/coherence/client.py

@@ -517,6 +517,17 @@ async def is_empty(self) -> bool:
         :return: `true` if this map contains no key-value mappings.
         """
 
+    @abc.abstractmethod
+    async def is_ready(self) -> bool:
+        """
+        Returns `true` if this map is ready to be used.
+        An example of when this method would return `false` would be where a
+        partitioned cache service that owns this cache has no storage-enabled
+        members.
+
+        :return: `true` if this map is ready to be used.
+        """
+
     @abc.abstractmethod
     async def size(self) -> int:
         """
@@ -846,6 +857,20 @@ async def is_empty(self) -> bool:
         v = await self._client_stub.isEmpty(r)
         return self._request_factory.serializer.deserialize(v.value)
 
+    @_pre_call_cache
+    async def is_ready(self) -> bool:
+        try:
+            r = self._request_factory.is_ready_request()
+            v = await self._client_stub.isReady(r)
+            return self._request_factory.serializer.deserialize(v.value)
+        except grpc.aio._call.AioRpcError as e:
+            if e.code() == grpc.StatusCode.UNIMPLEMENTED:
+                raise OperationNotSupportedError(
+                    "This operation is not supported by the gRPC proxy for the connected Coherence Server."
+                    "Please upgrade to a version that supports this operation."
+                ) from e
+            raise  # Re-raise all other gRPC errors
+
     @_pre_call_cache
     async def size(self) -> int:
         r = self._request_factory.size_request()
@@ -1364,6 +1389,11 @@ async def is_empty(self) -> bool:
         await dispatcher.dispatch(self._stream_handler)
         return dispatcher.result()
 
+    async def is_ready(self) -> bool:
+        dispatcher: UnaryDispatcher[bool] = self._request_factory.is_ready_request()
+        await dispatcher.dispatch(self._stream_handler)
+        return dispatcher.result()
+
     @_pre_call_cache
     async def size(self) -> int:
         dispatcher: UnaryDispatcher[int] = self._request_factory.size_request()
@@ -2701,3 +2731,9 @@ async def handle_zero_id_response(self, response: ProxyResponse) -> None:
                     self._events_manager._emitter.emit(
                         MapLifecycleEvent.TRUNCATED.value, self._events_manager._named_map.name
                     )
+
+
+class OperationNotSupportedError(Exception):
+    """Exception raised when the requested operation is not supported by the server."""
+
+    pass

src/coherence/util.py

@@ -43,6 +43,7 @@
     InvokeAllRequest,
     InvokeRequest,
     IsEmptyRequest,
+    IsReadyRequest,
     KeySetRequest,
     MapListenerRequest,
     PageRequest,
@@ -557,6 +558,10 @@ def is_empty_request(self) -> IsEmptyRequest:
         r = IsEmptyRequest(scope=self._scope, cache=self._cache_name)
         return r
 
+    def is_ready_request(self) -> IsReadyRequest:
+        r = IsReadyRequest(scope=self._scope, cache=self._cache_name)
+        return r
+
     def size_request(self) -> SizeRequest:
         r = SizeRequest(scope=self._scope, cache=self._cache_name)
         return r
@@ -1020,6 +1025,16 @@ def is_empty_request(self) -> UnaryDispatcher[bool]:
             self.request_timeout, self.create_proxy_request(named_cache_request), BoolValueTransformer(self._serializer)
         )
 
+    def is_ready_request(self) -> UnaryDispatcher[bool]:
+        named_cache_request = NamedCacheRequest(
+            type=NamedCacheRequestType.IsReady,
+            cacheId=self.cache_id,
+        )
+
+        return UnaryDispatcher(
+            self.request_timeout, self.create_proxy_request(named_cache_request), BoolValueTransformer(self._serializer)
+        )
+
     def size_request(self) -> UnaryDispatcher[int]:
         named_cache_request = NamedCacheRequest(
             type=NamedCacheRequestType.Size,

tests/e2e/test_client.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2022, 2024, Oracle and/or its affiliates.
+# Copyright (c) 2022, 2025, Oracle and/or its affiliates.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # https://oss.oracle.com/licenses/upl.
 
@@ -12,8 +12,8 @@
 from grpc.aio import AioRpcError
 
 import tests
-from coherence import Aggregators, Filters, MapEntry, NamedCache, Session, request_timeout
-from coherence.client import CacheOptions
+from coherence import COH_LOG, Aggregators, Filters, MapEntry, NamedCache, Session, request_timeout
+from coherence.client import CacheOptions, OperationNotSupportedError
 from coherence.event import MapLifecycleEvent
 from coherence.extractor import ChainedExtractor, Extractors, UniversalExtractor
 from coherence.processor import ExtractorProcessor
@@ -363,6 +363,16 @@ async def test_is_empty(cache: NamedCache[str, str]) -> None:
     assert r is True
 
 
+@pytest.mark.asyncio
+async def test_is_ready(cache: NamedCache[str, str]) -> None:
+    try:
+        r: bool = await cache.is_ready()
+        assert r is True
+    except OperationNotSupportedError as e:
+        COH_LOG.info("Skipped " + str(e))
+        pytest.skip("Server version does not support is_ready method.")
+
+
 # noinspection PyShadowingNames
 @pytest.mark.asyncio
 async def test_size(cache: NamedCache[str, str]) -> None: