io.grpc.ServerServiceDefinition Maven / Gradle / Ivy
/*
* Copyright 2014 The 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.
*/
package io.grpc;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/** Definition of a service to be exposed via a Server. */
public final class ServerServiceDefinition {
/** Convenience that constructs a {@link ServiceDescriptor} simultaneously. */
public static Builder builder(String serviceName) {
return new Builder(serviceName);
}
public static Builder builder(ServiceDescriptor serviceDescriptor) {
return new Builder(serviceDescriptor);
}
private final ServiceDescriptor serviceDescriptor;
private final Map> methods;
private ServerServiceDefinition(
ServiceDescriptor serviceDescriptor, Map> methods) {
this.serviceDescriptor = checkNotNull(serviceDescriptor, "serviceDescriptor");
this.methods = Collections.unmodifiableMap(new HashMap<>(methods));
}
/**
* The descriptor for the service.
*/
public ServiceDescriptor getServiceDescriptor() {
return serviceDescriptor;
}
/**
* Gets all the methods of service.
*/
public Collection> getMethods() {
return methods.values();
}
/**
* Look up a method by its fully qualified name.
*
* @param methodName the fully qualified name without leading slash. E.g., "com.foo.Foo/Bar"
*/
@Internal
public ServerMethodDefinition getMethod(String methodName) {
return methods.get(methodName);
}
/**
* Builder for constructing Service instances.
*/
public static final class Builder {
private final String serviceName;
private final ServiceDescriptor serviceDescriptor;
private final Map> methods = new HashMap<>();
private Builder(String serviceName) {
this.serviceName = checkNotNull(serviceName, "serviceName");
this.serviceDescriptor = null;
}
private Builder(ServiceDescriptor serviceDescriptor) {
this.serviceDescriptor = checkNotNull(serviceDescriptor, "serviceDescriptor");
this.serviceName = serviceDescriptor.getName();
}
/**
* Add a method to be supported by the service.
*
* @param method the {@link MethodDescriptor} of this method.
* @param handler handler for incoming calls
*/
public Builder addMethod(
MethodDescriptor method, ServerCallHandler handler) {
return addMethod(ServerMethodDefinition.create(
checkNotNull(method, "method must not be null"),
checkNotNull(handler, "handler must not be null")));
}
/** Add a method to be supported by the service. */
public Builder addMethod(ServerMethodDefinition def) {
MethodDescriptor method = def.getMethodDescriptor();
checkArgument(
serviceName.equals(method.getServiceName()),
"Method name should be prefixed with service name and separated with '/'. "
+ "Expected service name: '%s'. Actual fully qualifed method name: '%s'.",
serviceName, method.getFullMethodName());
String name = method.getFullMethodName();
checkState(!methods.containsKey(name), "Method by same name already registered: %s", name);
methods.put(name, def);
return this;
}
/**
* Construct new ServerServiceDefinition.
*/
public ServerServiceDefinition build() {
ServiceDescriptor serviceDescriptor = this.serviceDescriptor;
if (serviceDescriptor == null) {
List> methodDescriptors
= new ArrayList<>(methods.size());
for (ServerMethodDefinition serverMethod : methods.values()) {
methodDescriptors.add(serverMethod.getMethodDescriptor());
}
serviceDescriptor = new ServiceDescriptor(serviceName, methodDescriptors);
}
Map> tmpMethods = new HashMap<>(methods);
for (MethodDescriptor descriptorMethod : serviceDescriptor.getMethods()) {
ServerMethodDefinition removed = tmpMethods.remove(
descriptorMethod.getFullMethodName());
if (removed == null) {
throw new IllegalStateException(
"No method bound for descriptor entry " + descriptorMethod.getFullMethodName());
}
if (removed.getMethodDescriptor() != descriptorMethod) {
throw new IllegalStateException(
"Bound method for " + descriptorMethod.getFullMethodName()
+ " not same instance as method in service descriptor");
}
}
if (tmpMethods.size() > 0) {
throw new IllegalStateException(
"No entry in descriptor matching bound method "
+ tmpMethods.values().iterator().next().getMethodDescriptor().getFullMethodName());
}
return new ServerServiceDefinition(serviceDescriptor, methods);
}
}
}