--- /dev/null
+/*
+ *
+ * Copyright 2015 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 GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H
+
+#include <grpc/support/port_platform.h>
+
+#include <grpc/support/string_util.h>
+
+#include "src/core/ext/filters/client_channel/resolver.h"
+#include "src/core/lib/gprpp/abstract.h"
+#include "src/core/lib/gprpp/memory.h"
+#include "src/core/lib/gprpp/orphanable.h"
+#include "src/core/lib/iomgr/pollset_set.h"
+#include "src/core/lib/uri/uri_parser.h"
+
+namespace grpc_core {
+
+struct ResolverArgs {
+ /// The parsed URI to resolve.
+ grpc_uri* uri = nullptr;
+ /// Channel args to be included in resolver results.
+ const grpc_channel_args* args = nullptr;
+ /// Used to drive I/O in the name resolution process.
+ grpc_pollset_set* pollset_set = nullptr;
+ /// The combiner under which all resolver calls will be run.
+ grpc_combiner* combiner = nullptr;
+ /// The result handler to be used by the resolver.
+ UniquePtr<Resolver::ResultHandler> result_handler;
+};
+
+class ResolverFactory {
+ public:
+ /// Returns a bool indicating whether the input uri is valid to create a
+ /// resolver.
+ virtual bool IsValidUri(const grpc_uri* uri) const GRPC_ABSTRACT;
+
+ /// Returns a new resolver instance.
+ virtual OrphanablePtr<Resolver> CreateResolver(ResolverArgs args) const
+ GRPC_ABSTRACT;
+
+ /// Returns a string representing the default authority to use for this
+ /// scheme.
+ virtual UniquePtr<char> GetDefaultAuthority(grpc_uri* uri) const {
+ const char* path = uri->path;
+ if (path[0] == '/') ++path;
+ return UniquePtr<char>(gpr_strdup(path));
+ }
+
+ /// Returns the URI scheme that this factory implements.
+ /// Caller does NOT take ownership of result.
+ virtual const char* scheme() const GRPC_ABSTRACT;
+
+ virtual ~ResolverFactory() {}
+
+ GRPC_ABSTRACT_BASE_CLASS
+};
+
+} // namespace grpc_core
+
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FACTORY_H */