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/*
* Copyright 2013 the original author or 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 ratpack.server;
import ratpack.api.Nullable;
import ratpack.func.Action;
import ratpack.impose.Impositions;
import ratpack.server.internal.DefaultRatpackServer;
/**
* The entry point for creating and starting a Ratpack application.
*
* The {@link #of(Action)} static method is used to create a server.
*
{@code
* import ratpack.server.RatpackServer;
* import ratpack.server.ServerConfig;
*
* import ratpack.test.ServerBackedApplicationUnderTest;
* import static org.junit.Assert.*;
*
* public class Example {
* public static void main(String... args) throws Exception {
* RatpackServer server = RatpackServer.of(s -> s
* .serverConfig(ServerConfig.embedded()) // base server configuration (e.g. port) - optional
* .registryOf(r -> r.add(String.class, "foo")) // registry of supporting objects - optional
* .handlers(chain -> chain // request handlers - required
* .get("a", ctx -> ctx.render(ctx.get(String.class) + " 1"))
* .get("b", ctx -> ctx.render(ctx.get(String.class) + " 2"))
* )
* );
*
* // this method starts the server, via server.start() and then calls server.stop()
* ServerBackedApplicationUnderTest.of(server).test(httpClient -> {
* assertEquals("foo 1", httpClient.getText("a"));
* assertEquals("foo 2", httpClient.getText("b"));
* });
* }
* }
* }
*
* Server objects are thread safe in that every instance method is {@code synchronized}.
*
* @see RatpackServerSpec
* @see ratpack.service.Service
* @see #of(Action)
*/
public interface RatpackServer {
// TODO document the contents of the server registry, and the way that the user registry is joined on to it
/**
* Creates a new, unstarted, Ratpack server from the given definition.
*
* The action argument effectively serves as the definition of the server.
* It receives a mutable server builder style object, a {@link RatpackServerSpec}.
* The action is retained internally by the server, and invoked again if the {@link #reload()} method is called.
*
* @param definition the server definition
* @return a Ratpack server
* @see RatpackServerSpec
* @throws Exception any thrown by creating the server
*/
static RatpackServer of(Action definition) throws Exception {
return new DefaultRatpackServer(definition, Impositions.current());
}
/**
* Convenience method to {@link #of(Action) define} and {@link #start()} the server in one go.
*
* @param definition the server definition
* @return the newly created and started server
* @throws Exception any thrown by {@link #of(Action)} or {@link #start()}
*/
static RatpackServer start(Action definition) throws Exception {
RatpackServer server = of(definition);
server.start();
return server;
}
/**
* The URL scheme the server uses.
*
* @return either http or https depending on whether the server is using SSL or not
*/
String getScheme();
/**
* The actual port that the application is bound to.
*
* @return the actual port that the application is bound to, or -1 if the server is not running
*/
int getBindPort();
/**
* The actual host/ip that the application is bound to.
*
* @return the actual host/ip that the application is bound to, or null if this server is not running
*/
@Nullable
String getBindHost();
/**
* Returns {@code true} if the server is running.
*
* @return {@code true} if the server is running
*/
boolean isRunning();
/**
* Starts the server, returning as soon as the server is up and ready to receive requests.
*
* This will create new threads that are not daemonized.
* That is, a running Ratpack server will prevent the JVM from shutting down unless {@link System#exit(int)} is called.
* It is generally advisable to {@link #stop() stop the server} instead of forcefully killing the JVM.
*
* Calling this method while the server {@link #isRunning() is running} has no effect.
*
* @throws Exception if the server could not be started
*/
void start() throws Exception;
/**
* Stops the server, returning as soon as the server has stopped receiving requests.
*
* This method will terminate all threads started by the server.
*
* @throws Exception if the server could not be stopped cleanly
*/
void stop() throws Exception;
/**
* Reloads the server from its definition function.
*
* The server definition will be rebuilt by executing the function used to create the server.
* Depending on the function's implementation, a different definition may result.
* This is effectively configuration reloading mechanism.
*
{@code
* import ratpack.server.RatpackServer;
* import ratpack.test.ApplicationUnderTest;
* import static org.junit.Assert.*;
*
* public class Example {
* public static void main(String... args) throws Exception {
* String[] holder = new String[]{"foo"};
*
* RatpackServer server = RatpackServer.of(s -> s
* .serverConfig(ServerConfig.embedded())
* .registry(r -> r.add(String.class, holder[0]))
* .all(registry -> (ctx) -> ctx.render(ctx.get(String.class)))
* );
*
* ApplicationUnderTest.of(server).test(httpClient -> {
* assertEquals("foo", httpClient.getText());
*
* // change data read in definition function…
* holder[0] = "bar";
*
* // value unchanged…
* assertEquals("foo", httpClient.getText());
*
* // reload server…
* server.reload();
*
* // value has changed…
* assertEquals("bar", httpClient.getText());
* });
* }
* }
* }
*
* If the server is running, it will be {@link #stop() stopped} and then {@link #start() started}.
* If it is not running, the definition function will still be executed straight away and the new definition used next time the server is started.
*
* @return this
* @throws Exception any thrown from the definition function, {@link #stop()} or {@link #start()} methods.
*/
RatpackServer reload() throws Exception;
}