GRPC Core  9.0.0
fake_resolver.h
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2 // Copyright 2016 gRPC authors.
3 //
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5 // you may not use this file except in compliance with the License.
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16 
17 #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H
18 #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H
19 
21 
26 
27 #define GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR \
28  "grpc.fake_resolver.response_generator"
29 
30 namespace grpc_core {
31 
32 class FakeResolver;
33 
38 // TODO(roth): I would ideally like this to be InternallyRefCounted
39 // instead of RefCounted, but external refs are currently needed to
40 // encode this in channel args. Once channel_args are converted to C++,
41 // see if we can find a way to fix this.
43  : public RefCounted<FakeResolverResponseGenerator> {
44  public:
47 
48  // Instructs the fake resolver associated with the response generator
49  // instance to trigger a new resolution with the specified result. If the
50  // resolver is not available yet, delays response setting until it is. This
51  // can be called at most once before the resolver is available.
52  void SetResponse(Resolver::Result result);
53 
54  // Sets the re-resolution response, which is returned by the fake resolver
55  // when re-resolution is requested (via \a RequestReresolutionLocked()).
56  // The new re-resolution response replaces any previous re-resolution
57  // response that may have been set by a previous call.
59 
60  // Unsets the re-resolution response. After this, the fake resolver will
61  // not return anything when \a RequestReresolutionLocked() is called.
63 
64  // Tells the resolver to return a transient failure.
65  void SetFailure();
66 
67  // Same as SetFailure(), but instead of returning the error
68  // immediately, waits for the next call to RequestReresolutionLocked().
70 
71  // Returns a channel arg containing \a generator.
73 
74  // Returns the response generator in \a args, or null if not found.
76  const grpc_channel_args* args);
77 
78  private:
79  friend class FakeResolver;
80  // Set the corresponding FakeResolver to this generator.
81  void SetFakeResolver(RefCountedPtr<FakeResolver> resolver);
82 
83  static void SetResponseLocked(void* arg, grpc_error* error);
84  static void SetReresolutionResponseLocked(void* arg, grpc_error* error);
85  static void SetFailureLocked(void* arg, grpc_error* error);
86 
87  // Mutex protecting the members below.
88  Mutex mu_;
90  Resolver::Result result_;
91  bool has_result_ = false;
92 };
93 
94 } // namespace grpc_core
95 
96 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H \
97  */
~FakeResolverResponseGenerator()
Definition: fake_resolver.cc:175
FakeResolverResponseGenerator()
Definition: fake_resolver.cc:173
An array of arguments that can be passed around.
Definition: grpc_types.h:132
void UnsetReresolutionResponse()
Definition: fake_resolver.cc:246
Definition: error_internal.h:39
static grpc_arg MakeChannelArg(FakeResolverResponseGenerator *generator)
Definition: fake_resolver.cc:347
A single argument...
Definition: grpc_types.h:103
void SetFailureOnReresolution()
Definition: fake_resolver.cc:287
Definition: fake_resolver.cc:50
Round Robin Policy.
Definition: backend_metric.cc:24
void SetReresolutionResponse(Resolver::Result result)
Definition: fake_resolver.cc:228
static RefCountedPtr< FakeResolverResponseGenerator > GetFromArgs(const grpc_channel_args *args)
Definition: fake_resolver.cc:358
void SetFailure()
Definition: fake_resolver.cc:272
Results returned by the resolver.
Definition: resolver.h:52
Definition: ref_counted_ptr.h:35
void SetResponse(Resolver::Result result)
Definition: fake_resolver.cc:197
Definition: ref_counted.h:248
Definition: sync.h:40
A mechanism for generating responses for the fake resolver.
Definition: fake_resolver.h:42