1 // 2 // Copyright 2015 gRPC authors. 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #ifndef GRPC_SRC_CORE_LIB_RESOLVER_RESOLVER_FACTORY_H 18 #define GRPC_SRC_CORE_LIB_RESOLVER_RESOLVER_FACTORY_H 19 20 #include <grpc/support/port_platform.h> 21 22 #include <memory> 23 #include <string> 24 25 #include "absl/strings/string_view.h" 26 #include "absl/strings/strip.h" 27 28 #include "src/core/lib/channel/channel_args.h" 29 #include "src/core/lib/gprpp/orphanable.h" 30 #include "src/core/lib/iomgr/iomgr_fwd.h" 31 #include "src/core/lib/resolver/resolver.h" 32 #include "src/core/lib/uri/uri_parser.h" 33 34 namespace grpc_core { 35 36 // TODO(yashkt): Move WorkSerializer to its own Bazel target, depend on that 37 // target from this one, and remove this forward declaration. 38 class WorkSerializer; 39 40 struct ResolverArgs { 41 /// The parsed URI to resolve. 42 URI uri; 43 /// Channel args to be included in resolver results. 44 ChannelArgs args; 45 /// Used to drive I/O in the name resolution process. 46 grpc_pollset_set* pollset_set = nullptr; 47 /// The work_serializer under which all resolver calls will be run. 48 std::shared_ptr<WorkSerializer> work_serializer; 49 /// The result handler to be used by the resolver. 50 std::unique_ptr<Resolver::ResultHandler> result_handler; 51 }; 52 53 class ResolverFactory { 54 public: ~ResolverFactory()55 virtual ~ResolverFactory() {} 56 57 /// Returns the URI scheme that this factory implements. 58 /// Must not include any upper-case characters. 59 virtual absl::string_view scheme() const = 0; 60 61 /// Returns a bool indicating whether the input uri is valid to create a 62 /// resolver. 63 virtual bool IsValidUri(const URI& uri) const = 0; 64 65 /// Returns a new resolver instance. 66 virtual OrphanablePtr<Resolver> CreateResolver(ResolverArgs args) const = 0; 67 68 /// Returns a string representing the default authority to use for this 69 /// scheme. GetDefaultAuthority(const URI & uri)70 virtual std::string GetDefaultAuthority(const URI& uri) const { 71 return std::string(absl::StripPrefix(uri.path(), "/")); 72 } 73 }; 74 75 } // namespace grpc_core 76 77 #endif // GRPC_SRC_CORE_LIB_RESOLVER_RESOLVER_FACTORY_H 78