GRPC C++  1.64.0
channel_interface.h
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18 
19 #ifndef GRPCPP_IMPL_CHANNEL_INTERFACE_H
20 #define GRPCPP_IMPL_CHANNEL_INTERFACE_H
21 
23 #include <grpcpp/impl/call.h>
24 #include <grpcpp/support/status.h>
25 #include <grpcpp/support/time.h>
26 
27 namespace grpc {
28 template <class R>
29 class ClientReader;
30 template <class W>
31 class ClientWriter;
32 template <class W, class R>
33 class ClientReaderWriter;
34 namespace internal {
35 template <class InputMessage, class OutputMessage>
36 class CallbackUnaryCallImpl;
37 template <class R>
39 template <class W>
41 template <class W, class R>
44 template <class W, class R>
46 template <class R>
48 template <class W>
51 } // namespace internal
52 
53 class ChannelInterface;
54 class ClientContext;
55 class CompletionQueue;
56 
57 namespace experimental {
58 class DelegatingChannel;
59 }
60 
61 namespace internal {
62 class Call;
63 class CallOpSetInterface;
64 class RpcMethod;
65 class InterceptedChannel;
66 template <class InputMessage, class OutputMessage>
67 class BlockingUnaryCallImpl;
68 } // namespace internal
69 
72  public:
73  virtual ~ChannelInterface() {}
76  virtual grpc_connectivity_state GetState(bool try_to_connect) = 0;
77 
80  template <typename T>
81  void NotifyOnStateChange(grpc_connectivity_state last_observed, T deadline,
82  grpc::CompletionQueue* cq, void* tag) {
83  TimePoint<T> deadline_tp(deadline);
84  NotifyOnStateChangeImpl(last_observed, deadline_tp.raw_time(), cq, tag);
85  }
86 
89  template <typename T>
90  bool WaitForStateChange(grpc_connectivity_state last_observed, T deadline) {
91  TimePoint<T> deadline_tp(deadline);
92  return WaitForStateChangeImpl(last_observed, deadline_tp.raw_time());
93  }
94 
96  template <typename T>
97  bool WaitForConnected(T deadline) {
99  while ((state = GetState(true)) != GRPC_CHANNEL_READY) {
100  if (!WaitForStateChange(state, deadline)) return false;
101  }
102  return true;
103  }
104 
105  private:
106  template <class R>
107  friend class grpc::ClientReader;
108  template <class W>
109  friend class grpc::ClientWriter;
110  template <class W, class R>
112  template <class R>
114  template <class W>
116  template <class W, class R>
119  template <class W, class R>
121  template <class R>
123  template <class W>
126  template <class InputMessage, class OutputMessage>
128  template <class InputMessage, class OutputMessage>
133  virtual internal::Call CreateCall(const internal::RpcMethod& method,
134  grpc::ClientContext* context,
135  grpc::CompletionQueue* cq) = 0;
136  virtual void PerformOpsOnCall(internal::CallOpSetInterface* ops,
137  internal::Call* call) = 0;
138  virtual void* RegisterMethod(const char* method) = 0;
139  virtual void NotifyOnStateChangeImpl(grpc_connectivity_state last_observed,
140  gpr_timespec deadline,
142  void* tag) = 0;
143  virtual bool WaitForStateChangeImpl(grpc_connectivity_state last_observed,
144  gpr_timespec deadline) = 0;
145 
146  // EXPERIMENTAL
147  // This is needed to keep codegen_test_minimal happy. InterceptedChannel needs
148  // to make use of this but can't directly call Channel's implementation
149  // because of the test.
150  // Returns an empty Call object (rather than being pure) since this is a new
151  // method and adding a new pure method to an interface would be a breaking
152  // change (even though this is private and non-API)
153  virtual internal::Call CreateCallInternal(
154  const internal::RpcMethod& /*method*/, grpc::ClientContext* /*context*/,
155  grpc::CompletionQueue* /*cq*/, size_t /*interceptor_pos*/) {
156  return internal::Call();
157  }
158 
159  // A method to get the callbackable completion queue associated with this
160  // channel. If the return value is nullptr, this channel doesn't support
161  // callback operations.
162  // TODO(vjpai): Consider a better default like using a global CQ
163  // Returns nullptr (rather than being pure) since this is a post-1.0 method
164  // and adding a new pure method to an interface would be a breaking change
165  // (even though this is private and non-API)
166  virtual grpc::CompletionQueue* CallbackCQ() { return nullptr; }
167 };
168 } // namespace grpc
169 
170 #endif // GRPCPP_IMPL_CHANNEL_INTERFACE_H
time.h
grpc::ClientWriter
Synchronous (blocking) client-side API for doing client-streaming RPCs, where the outgoing message st...
Definition: client_context.h:83
grpc
An Alarm posts the user-provided tag to its associated completion queue or invokes the user-provided ...
Definition: alarm.h:33
grpc::internal::ClientAsyncReaderWriterFactory
Definition: channel_interface.h:42
grpc::internal::BlockingUnaryCallImpl
Definition: client_context.h:103
grpc::internal::Call
Straightforward wrapping of the C call object.
Definition: call.h:36
status.h
grpc::ChannelInterface::WaitForStateChange
bool WaitForStateChange(grpc_connectivity_state last_observed, T deadline)
Blocking wait for channel state change or deadline expiration.
Definition: channel_interface.h:90
grpc::internal::ClientAsyncReaderFactory
Definition: channel_interface.h:38
grpc::ClientReader
Synchronous (blocking) client-side API for doing server-streaming RPCs, where the stream of messages ...
Definition: client_context.h:81
grpc::internal::ClientCallbackWriterFactory
Definition: channel_interface.h:49
grpc::ClientContext
A ClientContext allows the person implementing a service client to:
Definition: client_context.h:195
grpc_connectivity_state
grpc_connectivity_state
Connectivity state of a channel.
Definition: connectivity_state.h:30
grpc::internal::ClientCallbackReaderWriterFactory
Definition: channel_interface.h:45
grpc::internal::CallOpSetInterface
An abstract collection of call ops, used to generate the grpc_call_op structure to pass down to the l...
Definition: call_op_set_interface.h:36
grpc::internal::CallbackUnaryCallImpl
Definition: client_context.h:68
connectivity_state.h
grpc::ChannelInterface::WaitForConnected
bool WaitForConnected(T deadline)
Wait for this channel to be connected.
Definition: channel_interface.h:97
grpc::TimePoint::raw_time
gpr_timespec raw_time()=delete
grpc::experimental::DelegatingChannel
Definition: delegating_channel.h:29
grpc::ChannelInterface
Codegen interface for grpc::Channel.
Definition: channel_interface.h:71
grpc::internal::ClientAsyncResponseReaderHelper
Definition: async_unary_call.h:80
grpc::internal::InterceptedChannel
An InterceptedChannel is available to client Interceptors.
Definition: intercepted_channel.h:35
grpc::internal::ClientCallbackUnaryFactory
Definition: client_callback.h:1204
grpc::ChannelInterface::~ChannelInterface
virtual ~ChannelInterface()
Definition: channel_interface.h:73
grpc::ChannelInterface::NotifyOnStateChange
void NotifyOnStateChange(grpc_connectivity_state last_observed, T deadline, grpc::CompletionQueue *cq, void *tag)
Return the tag on cq when the channel state is changed or deadline expires.
Definition: channel_interface.h:81
grpc::ClientReaderWriter
Synchronous (blocking) client-side API for bi-directional streaming RPCs, where the outgoing message ...
Definition: client_context.h:85
grpc::ChannelInterface::GetState
virtual grpc_connectivity_state GetState(bool try_to_connect)=0
Get the current channel state.
call.h
grpc::CompletionQueue
A thin wrapper around grpc_completion_queue (see src/core/lib/surface/completion_queue....
Definition: completion_queue.h:105
grpc::internal::ClientCallbackReaderFactory
Definition: channel_interface.h:47
grpc::internal::ClientAsyncWriterFactory
Definition: channel_interface.h:40
grpc::internal::RpcMethod
Descriptor of an RPC method.
Definition: rpc_method.h:29
gpr_timespec
Analogous to struct timespec.
Definition: time.h:48
GRPC_CHANNEL_READY
@ GRPC_CHANNEL_READY
channel is ready for work
Definition: connectivity_state.h:36
grpc::TimePoint
If you are trying to use CompletionQueue::AsyncNext with a time class that isn't either gpr_timespec ...
Definition: time.h:40