1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
/*
*
* Copyright 2018 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#ifndef GRPCPP_IMPL_CODEGEN_SERVER_INTERCEPTOR_H
#define GRPCPP_IMPL_CODEGEN_SERVER_INTERCEPTOR_H
#include <atomic>
#include <vector>
#include <grpcpp/impl/codegen/interceptor.h>
#include <grpcpp/impl/codegen/rpc_method.h>
#include <grpcpp/impl/codegen/string_ref.h>
namespace grpc {
class ServerContextBase;
namespace internal {
class InterceptorBatchMethodsImpl;
}
namespace experimental {
class ServerRpcInfo;
// A factory interface for creation of server interceptors. A vector of
// factories can be provided to ServerBuilder which will be used to create a new
// vector of server interceptors per RPC. Server interceptor authors should
// create a subclass of ServerInterceptorFactorInterface which creates objects
// of their interceptors.
class ServerInterceptorFactoryInterface {
public:
virtual ~ServerInterceptorFactoryInterface() {}
// Returns a pointer to an Interceptor object on successful creation, nullptr
// otherwise. If nullptr is returned, this server interceptor factory is
// ignored for the purposes of that RPC.
virtual Interceptor* CreateServerInterceptor(ServerRpcInfo* info) = 0;
};
/// ServerRpcInfo represents the state of a particular RPC as it
/// appears to an interceptor. It is created and owned by the library and
/// passed to the CreateServerInterceptor method of the application's
/// ServerInterceptorFactoryInterface implementation
class ServerRpcInfo {
public:
/// Type categorizes RPCs by unary or streaming type
enum class Type { UNARY, CLIENT_STREAMING, SERVER_STREAMING, BIDI_STREAMING };
~ServerRpcInfo() {}
// Delete all copy and move constructors and assignments
ServerRpcInfo(const ServerRpcInfo&) = delete;
ServerRpcInfo& operator=(const ServerRpcInfo&) = delete;
ServerRpcInfo(ServerRpcInfo&&) = delete;
ServerRpcInfo& operator=(ServerRpcInfo&&) = delete;
// Getter methods
/// Return the fully-specified method name
const char* method() const { return method_; }
/// Return the type of the RPC (unary or a streaming flavor)
Type type() const { return type_; }
/// Return a pointer to the underlying ServerContext structure associated
/// with the RPC to support features that apply to it
ServerContextBase* server_context() { return ctx_; }
private:
static_assert(Type::UNARY ==
static_cast<Type>(internal::RpcMethod::NORMAL_RPC),
"violated expectation about Type enum");
static_assert(Type::CLIENT_STREAMING ==
static_cast<Type>(internal::RpcMethod::CLIENT_STREAMING),
"violated expectation about Type enum");
static_assert(Type::SERVER_STREAMING ==
static_cast<Type>(internal::RpcMethod::SERVER_STREAMING),
"violated expectation about Type enum");
static_assert(Type::BIDI_STREAMING ==
static_cast<Type>(internal::RpcMethod::BIDI_STREAMING),
"violated expectation about Type enum");
ServerRpcInfo(ServerContextBase* ctx, const char* method,
internal::RpcMethod::RpcType type)
: ctx_(ctx), method_(method), type_(static_cast<Type>(type)) {}
// Runs interceptor at pos \a pos.
void RunInterceptor(
experimental::InterceptorBatchMethods* interceptor_methods, size_t pos) {
GPR_CODEGEN_ASSERT(pos < interceptors_.size());
interceptors_[pos]->Intercept(interceptor_methods);
}
void RegisterInterceptors(
const std::vector<
std::unique_ptr<experimental::ServerInterceptorFactoryInterface>>&
creators) {
for (const auto& creator : creators) {
auto* interceptor = creator->CreateServerInterceptor(this);
if (interceptor != nullptr) {
interceptors_.push_back(
std::unique_ptr<experimental::Interceptor>(interceptor));
}
}
}
void Ref() { ref_.fetch_add(1, std::memory_order_relaxed); }
void Unref() {
if (GPR_UNLIKELY(ref_.fetch_sub(1, std::memory_order_acq_rel) == 1)) {
delete this;
}
}
ServerContextBase* ctx_ = nullptr;
const char* method_ = nullptr;
const Type type_;
std::atomic<intptr_t> ref_{1};
std::vector<std::unique_ptr<experimental::Interceptor>> interceptors_;
friend class internal::InterceptorBatchMethodsImpl;
friend class grpc::ServerContextBase;
};
} // namespace experimental
} // namespace grpc
#endif // GRPCPP_IMPL_CODEGEN_SERVER_INTERCEPTOR_H
|
