juneau-doc/docs/Topics/09.juneau-rest-client/01.RestProxies.html

<!--
/***************************************************************************************************************************
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 ***************************************************************************************************************************/
 -->

REST Proxies

<p>
	The <c>juneau-rest-client</c> library can also be used to define interface proxies against 3rd-party REST interfaces.
	This is an extremely powerful feature that allows you to quickly define easy-to-use interfaces against 
	virtually any REST interface.
</p>
<p>
	Remote resources are instantiated using one of the following methods:
</p>
<ul class='javatree'>
	<li class='jc'>{@link oajrc.RestClient}
	<ul>
		<li class='jm'>{@link oajrc.RestClient#getRemote(Class) getRemote(Class)}
		<li class='jm'>{@link oajrc.RestClient#getRemote(Class,Object) getRemote(Class,Object)}
		<li class='jm'>{@link oajrc.RestClient#getRemote(Class,Object,Serializer,Parser) getRemote(Class,Object,Serializer,Parser)}
	</ul>
</ul>
<p>
	Annotations are used on the interface and interface methods to specify how to convert input and output to HTTP headers, query parameters, form 
	post parameters, or request/response bodies.
</p>
<ul class='javatree'>
	<li class='jp'>{@link oaj.http.remote}
	<ul>
		<li class='ja'>{@link oaj.http.remote.Remote}
		<li class='ja'>{@link oaj.http.remote.RemoteMethod}
	</ul>
	<li class='jp'>{@link oaj.http.annotation}
	<ul>
		<li class='ja'>{@link oaj.http.annotation.Body}
		<li class='ja'>{@link oaj.http.annotation.Header}
		<li class='ja'>{@link oaj.http.annotation.FormData}
		<li class='ja'>{@link oaj.http.annotation.Query}
		<li class='ja'>{@link oaj.http.annotation.Path}
		<li class='ja'>{@link oaj.http.annotation.Request}
		<li class='ja'>{@link oaj.http.annotation.Response}
	</ul>
</ul>

<h5 class='figure'>Example:</h5>
<p class='bpcode w800'>	
	<ja>@Remote</ja>(path=<js>"/petstore"</js>)
	<jk>public interface</jk> PetStore {
		
		<ja>@RemoteMethod</ja>(httpMethod=<jsf>POST</jsf>, path=<js>"/pets"</js>)
		String addPet(
			<ja>@Body</ja> CreatePet pet, 
			<ja>@Header</ja>(<js>"E-Tag"</js>) UUID etag, 
			<ja>@Query</ja>(<js>"debug"</js>) <jk>boolean</jk> debug
		);
	}
</p>
<p class='bpcode w800'>	
	<jc>// Use a RestClient with default Simple JSON support.</jc>
	<jk>try</jk> (RestClient client = RestClient.<jsm>create</jsm>().simpleJson().build()) {
		PetStore store = client.getRemote(PetStore.<jk>class</jk>, <js>"http://localhost:10000"</js>);
		CreatePet pet = <jk>new</jk> CreatePet(<js>"Fluffy"</js>, 9.99);
		String response = store.createPet(pet, UUID.<jsm>randomUUID</jsm>(), <jk>true</jk>);
	}
</p>
<p>
	The call above translates to the following REST call:
</p>
<p class='bpcode w800'>
	POST http://localhost:10000/petstore/pets?debug=true HTTP/1.1
	Accept: application/json
	Content-Type: application/json
	E-Tag: 475588d4-0b27-4f56-9296-cc683251d314
	
	{
		name: 'Fluffy',
		price: 9.99 
	}
</p>