001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.http.annotation;
018
019import static java.lang.annotation.ElementType.*;
020import static java.lang.annotation.RetentionPolicy.*;
021
022import java.lang.annotation.*;
023
024import org.apache.juneau.annotation.*;
025import org.apache.juneau.httppart.*;
026import org.apache.juneau.oapi.*;
027
028/**
029 * REST request path annotation.
030 *
031 * <p>
032 * Identifies a POJO to be used as a path entry on an HTTP request.
033 *
034 * <p>
035 * Can be used in the following locations:
036 * <ul>
037 *    <li>Arguments and argument-types of server-side <ja>@RestOp</ja>-annotated methods.
038 *    <li>Arguments and argument-types of client-side <ja>@RemoteResource</ja>-annotated interfaces.
039 *    <li>Methods and return types of server-side and client-side <ja>@Request</ja>-annotated interfaces.
040 * </ul>
041 *
042 * <h5 class='topic'>Arguments and argument-types of server-side @RestOp-annotated methods</h5>
043 * <p>
044 * Annotation that can be applied to a parameter of a <ja>@RestOp</ja>-annotated method to identify it as a variable
045 * in a URL path pattern.
046 *
047 * <h5 class='section'>Example:</h5>
048 * <p class='bjava'>
049 *    <ja>@RestGet</ja>(<js>"/myurl/{foo}/{bar}/{baz}/*"</js>)
050 *    <jk>public void</jk> doGet(
051 *          <ja>@Path</ja>(<js>"foo"</js>) String <jv>foo</jv>,
052 *          <ja>@Path</ja>(<js>"bar"</js>) <jk>int</jk> <jv>bar</jv>,
053 *          <ja>@Path</ja>(<js>"baz"</js>) UUID <jv>baz</jv>,
054 *          <ja>@Path</ja>(<js>"/*"</js>) String <jv>remainder</jv>,
055 *       ) {...}
056 * </p>
057 *
058 * <p>
059 * The special name <js>"/*"</js> is used to retrieve the path remainder after the path match (i.e. the part that matches <js>"/*"</js>).
060 *
061 * <h5 class='section'>See Also:</h5><ul>
062 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauBeanSwagger2">juneau-bean-swagger-v2</a>
063 *    <li class='extlink'><a class='doclink' href='https://swagger.io/specification/v2#parameterObject'>Swagger Parameter Object</a>
064 * </ul>
065 *
066 * <h5 class='topic'>Arguments and argument-types of client-side @RemoteResource-annotated interfaces</h5>
067 * <p>
068 * Annotation applied to Java method arguments of interface proxies to denote that they are path variables on the request.
069 *
070 * <h5 class='section'>See Also:</h5><ul>
071 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/Path">@Path</a>
072 * </ul>
073 *
074 * <h5 class='topic'>Methods and return types of server-side and client-side @Request-annotated interfaces</h5>
075 * <p>
076 * <h5 class='section'>See Also:</h5><ul>
077 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/Request">@Request</a>
078 * </ul>
079 *
080 * <h5 class='section'>See Also:</h5><ul>
081
082 * </ul>
083 */
084@Documented
085@Target({PARAMETER,METHOD,TYPE,FIELD})
086@Retention(RUNTIME)
087@Inherited
088@Repeatable(PathAnnotation.Array.class)
089@ContextApply(PathAnnotation.Applier.class)
090public @interface Path {
091
092   /**
093    * Default value for this parameter.
094    *
095    * @return The annotation value.
096    */
097   String def() default "";
098
099    /**
100     * Optional description for the exposed API.
101     *
102     * @return The annotation value.
103     * @since 9.2.0
104     */
105    String[] description() default {};
106
107    /**
108    * URL path variable name.
109    *
110    * <p>
111    * The path remainder after the path match can be referenced using the name <js>"/*"</js>.
112    * <br>The non-URL-decoded path remainder after the path match can be referenced using the name <js>"/**"</js>.
113    *
114    * <p>
115    * The value should be either a valid path parameter name, or <js>"*"</js> to represent multiple name/value pairs
116    *
117    * <p>
118    * A blank value (the default) has the following behavior:
119    * <ul class='spaced-list'>
120    *    <li>
121    *       If the data type is <c>NameValuePairs</c>, <c>Map</c>, or a bean,
122    *       then it's the equivalent to <js>"*"</js> which will cause the value to be treated as name/value pairs.
123    *
124    *       <h5 class='figure'>Examples:</h5>
125    *       <p class='bjava'>
126    *    <jc>// When used on a REST method</jc>
127    *    <ja>@RestPost</ja>
128    *    <jk>public void</jk> addPet(<ja>@Path</ja> JsonMap <jv>allPathParameters</jv>) {...}
129    *       </p>
130    *       <p class='bjava'>
131    *    <jc>// When used on a remote method parameter</jc>
132    *    <ja>@RemoteResource</ja>(path=<js>"/myproxy"</js>)
133    *    <jk>public interface</jk> MyProxy {
134    *
135    *       <jc>// Equivalent to @Path("*")</jc>
136    *       <ja>@RemoteGet</ja>(<js>"/mymethod/{foo}/{bar}"</js>)
137    *       String myProxyMethod1(<ja>@Path</ja> Map&lt;String,Object&gt; <jv>allPathParameters</jv>);
138    *    }
139    *       </p>
140    *       <p class='bjava'>
141    *    <jc>// When used on a request bean method</jc>
142    *    <jk>public interface</jk> MyRequest {
143    *
144    *       <jc>// Equivalent to @Path("*")</jc>
145    *       <ja>@Path</ja>
146    *       Map&lt;String,Object&gt; getPathVars();
147    *    }
148    *       </p>
149    *    </li>
150    *    <li>
151    *       If used on a request bean method, uses the bean property name.
152    *
153    *       <h5 class='figure'>Example:</h5>
154    *       <p class='bjava'>
155    *    <jk>public interface</jk> MyRequest {
156    *
157    *       <jc>// Equivalent to @Path("foo")</jc>
158    *       <ja>@Path</ja>
159    *       String getFoo();
160    *    }
161    * </ul>
162    *
163    * <p>
164    * The name field MUST correspond to the associated <a class="doclink" href="https://swagger.io/specification/v2#pathsPath">path</a> segment from the path field in the <a class="doclink" href="https://swagger.io/specification/v2#pathsObject">Paths Object</a>.
165    * See <a class="doclink" href="https://swagger.io/specification/v2#pathTemplating">Path Templating</a> for further information.
166    *
167    * <h5 class='section'>Notes:</h5><ul>
168    *    <li class='note'>
169    *       The format is plain-text.
170    * </ul>
171    *
172    * @return The annotation value.
173    */
174   String name() default "";
175
176   /**
177    * Dynamically apply this annotation to the specified classes.
178    *
179    * <h5 class='section'>See Also:</h5><ul>
180    *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/DynamicallyAppliedAnnotations">Dynamically Applied Annotations</a>
181    * </ul>
182    *
183    * @return The annotation value.
184    */
185   String[] on() default {};
186
187   /**
188    * Dynamically apply this annotation to the specified classes.
189    *
190    * <p>
191    * Identical to {@link #on()} except allows you to specify class objects instead of a strings.
192    *
193    * <h5 class='section'>See Also:</h5><ul>
194    *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/DynamicallyAppliedAnnotations">Dynamically Applied Annotations</a>
195    * </ul>
196    *
197    * @return The annotation value.
198    */
199   Class<?>[] onClass() default {};
200
201   /**
202    * Specifies the {@link HttpPartParser} class used for parsing strings to values.
203    *
204    * <p>
205    * Overrides for this part the part parser defined on the REST resource which by default is {@link OpenApiParser}.
206    *
207    * @return The annotation value.
208    */
209   Class<? extends HttpPartParser> parser() default HttpPartParser.Void.class;
210
211   /**
212    * <mk>schema</mk> field of the <a class='doclink' href='https://swagger.io/specification/v2#parameterObject'>Swagger Parameter Object</a>.
213    *
214    * <p>
215    * The schema defining the type used for parameter.
216    *
217    * <p>
218    * The {@link Schema @Schema} annotation can also be used standalone on the parameter or type.
219    * Values specified on this field override values specified on the type, and values specified on child types override values
220    * specified on parent types.
221    *
222    * <h5 class='section'>Used for:</h5>
223    * <ul class='spaced-list'>
224    *    <li>
225    *       Server-side schema-based parsing and parsing validation.
226    *    <li>
227    *       Server-side generated Swagger documentation.
228    *    <li>
229    *       Client-side schema-based serializing and serializing validation.
230    * </ul>
231    *
232    * @return The annotation value.
233    */
234   Schema schema() default @Schema;
235
236   /**
237    * Specifies the {@link HttpPartSerializer} class used for serializing values to strings.
238    *
239    * <p>
240    * Overrides for this part the part serializer defined on the REST client which by default is {@link OpenApiSerializer}.
241    *
242    * @return The annotation value.
243    */
244   Class<? extends HttpPartSerializer> serializer() default HttpPartSerializer.Void.class;
245
246   /**
247    * A synonym for {@link #name()}.
248    *
249    * <p>
250    * Allows you to use shortened notation if you're only specifying the name.
251    *
252    * <p>
253    * The following are completely equivalent ways of defining a path entry:
254    * <p class='bjava'>
255    *    <ja>@RestGet</ja>(<js>"/pet/{petId}"</js>)
256    *    <jk>public</jk> Pet getPet(<ja>@Path</ja>(name=<js>"petId"</js>) <jk>long</jk> <jv>petId</jv>) { ... }
257    * </p>
258    * <p class='bjava'>
259    *    <ja>@RestGet</ja>(<js>"/pet/{petId}"</js>)
260    *    <jk>public</jk> Pet getPet(<ja>@Path</ja>(<js>"petId"</js>) <jk>long</jk> <jv>petId</jv>) { ... }
261    * </p>
262    *
263    * @return The annotation value.
264    */
265   String value() default "";
266}