com.hedera.node.app.spi.Service Maven / Gradle / Ivy
/*
* Copyright (C) 2022-2024 Hedera Hashgraph, LLC
*
* 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.
*/
package com.hedera.node.app.spi;
import static java.util.Collections.emptySet;
import com.hedera.node.app.spi.state.SchemaRegistry;
import com.hedera.pbj.runtime.RpcServiceDefinition;
import edu.umd.cs.findbugs.annotations.NonNull;
import java.util.Set;
/**
* A definition of an interface that will be implemented by each conceptual "service" like
* crypto-service, token-service etc.,
*/
public interface Service {
/**
* A sort value for the service, used to determine the order in which service
* schemas are migrated.
*
* (FUTURE) This order should actually depend on the migration
* software version, because nothing prevents service {@code A} from needing
* to precede service {@code B} in version {@code N}; while at the same time
* {@code B} needing to precede {@code A} in version {@code N+1}. But this
* will require a significant restructuring in {@code hedera-app} and does
* not provide any current value, so we defer that work.
*
* @return the migrationOrder value
*/
default int migrationOrder() {
return 0;
}
/**
* Returns the name of the service. This name must be unique for each service deployed on the
* application.
*
* @return the name
*/
@NonNull
String getServiceName();
/**
* If this service exposes RPC endpoints, then this method returns the RPC service definitions.
* Otherwise, it returns an empty set.
*
* @return The RPC service definitions if this service is exposed via RPC.
*/
@NonNull
default Set rpcDefinitions() {
return emptySet();
}
/**
* Registers the schemas this service really uses with the given {@link SchemaRegistry}.
*
* @param registry the registry to register the schemas with
*/
default void registerSchemas(@NonNull final SchemaRegistry registry) {
// No-op
}
}