Add support for reusing a snippet to document common elements

This commit updates all of the Snippet implementations that take one
or more descriptors to provide an and method that can be used to
create a new Snippet that has additional descriptors.

Closes gh-168

docs/src/docs/asciidoc/documenting-your-api.adoc

@@ -445,6 +445,45 @@ When documenting HTTP Headers, the test will fail if a documented header is not
 the request or response.
 
 
+
+[[documenting-your-api-reusing-snippets]]
+=== Reusing snippets
+
+It's common for an API that's being documented to have some features that are common
+across several of its resources. To avoid repetition when documenting such resources a
+`Snippet` configured with the common elements can be reused.
+
+First, create the `Snippet` that describes the common elements. For example:
+
+[source,java,indent=0]
+----
+include::{examples-dir}/com/example/SnippetReuse.java[tags=field]
+----
+
+Second, use this snippet and add further descriptors that are resource-specific. For
+example:
+
+[source,java,indent=0,role="primary"]
+.MockMvc
+----
+include::{examples-dir}/com/example/mockmvc/MockMvcSnippetReuse.java[tags=use]
+----
+<1> Reuse the `pagingLinks` `Snippet` calling `and` to add descriptors that are specific
+	to the resource that is being documented.
+
+[source,java,indent=0,role="secondary"]
+.REST Assured
+----
+include::{examples-dir}/com/example/restassured/RestAssuredSnippetReuse.java[tags=use]
+----
+<1> Reuse the `pagingLinks` `Snippet` calling `and` to add descriptors that are specific
+	to the resource that is being documented.
+
+The result of the example is that links with the rels `first`, `last`, `next`, `previous`,
+`alpha`, and `bravo` are all documented.
+
+
+
 [[documenting-your-api-constraints]]
 === Documenting constraints
 

docs/src/test/java/com/example/SnippetReuse.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2012-2016 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 com.example;
+
+import org.springframework.restdocs.hypermedia.LinksSnippet;
+
+import static org.springframework.restdocs.hypermedia.HypermediaDocumentation.linkWithRel;
+import static org.springframework.restdocs.hypermedia.HypermediaDocumentation.links;
+
+public class SnippetReuse {
+
+	// tag::field[]
+	protected final LinksSnippet pagingLinks = links(
+			linkWithRel("first").optional().description("The first page of results"),
+			linkWithRel("last").optional().description("The last page of results"),
+			linkWithRel("next").optional().description("The next page of results"),
+			linkWithRel("prev").optional().description("The previous page of results"));
+	// end::field[]
+
+}

docs/src/test/java/com/example/mockmvc/MockMvcSnippetReuse.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2012-2016 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 com.example.mockmvc;
+
+import com.example.SnippetReuse;
+
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.springframework.restdocs.hypermedia.HypermediaDocumentation.linkWithRel;
+import static org.springframework.restdocs.mockmvc.MockMvcRestDocumentation.document;
+import static org.springframework.restdocs.mockmvc.RestDocumentationRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+public class MockMvcSnippetReuse extends SnippetReuse {
+	
+	private MockMvc mockMvc;
+	
+	public void documentation() throws Exception {
+		// tag::use[]
+		this.mockMvc.perform(get("/").accept(MediaType.APPLICATION_JSON))
+			.andExpect(status().isOk())
+			.andDo(document("example", this.pagingLinks.and( // <1>
+					linkWithRel("alpha").description("Link to the alpha resource"),
+					linkWithRel("bravo").description("Link to the bravo resource"))));
+		// end::use[]
+	}
+
+}

docs/src/test/java/com/example/restassured/RestAssuredSnippetReuse.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2012-2016 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 com.example.restassured;
+
+import com.example.SnippetReuse;
+import com.jayway.restassured.RestAssured;
+import com.jayway.restassured.specification.RequestSpecification;
+
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.springframework.restdocs.hypermedia.HypermediaDocumentation.linkWithRel;
+import static org.springframework.restdocs.restassured.RestAssuredRestDocumentation.document;
+
+public class RestAssuredSnippetReuse extends SnippetReuse {
+	
+	private RequestSpecification spec;
+	
+	public void documentation() throws Exception {
+		// tag::use[]
+		RestAssured.given(this.spec)
+			.accept("application/json")
+			.filter(document("example", this.pagingLinks.and( // <1>
+					linkWithRel("alpha").description("Link to the alpha resource"),
+					linkWithRel("bravo").description("Link to the bravo resource"))))
+			.get("/").then().assertThat().statusCode(is(200));
+		// end::use[]
+	}
+
+}

spring-restdocs-core/src/main/java/org/springframework/restdocs/headers/HeaderDocumentation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -55,7 +55,7 @@ public abstract class HeaderDocumentation {
 	 * @return the snippet that will document the request headers
 	 * @see #headerWithName(String)
 	 */
-	public static Snippet requestHeaders(HeaderDescriptor... descriptors) {
+	public static RequestHeadersSnippet requestHeaders(HeaderDescriptor... descriptors) {
 		return new RequestHeadersSnippet(Arrays.asList(descriptors));
 	}
 
@@ -72,7 +72,7 @@ public abstract class HeaderDocumentation {
 	 * @return the snippet that will document the request headers
 	 * @see #headerWithName(String)
 	 */
-	public static Snippet requestHeaders(Map<String, Object> attributes,
+	public static RequestHeadersSnippet requestHeaders(Map<String, Object> attributes,
 			HeaderDescriptor... descriptors) {
 		return new RequestHeadersSnippet(Arrays.asList(descriptors), attributes);
 	}
@@ -88,7 +88,8 @@ public abstract class HeaderDocumentation {
 	 * @return the snippet that will document the response headers
 	 * @see #headerWithName(String)
 	 */
-	public static Snippet responseHeaders(HeaderDescriptor... descriptors) {
+	public static ResponseHeadersSnippet responseHeaders(
+			HeaderDescriptor... descriptors) {
 		return new ResponseHeadersSnippet(Arrays.asList(descriptors));
 	}
 
@@ -106,7 +107,7 @@ public abstract class HeaderDocumentation {
 	 * @return the snippet that will document the response headers
 	 * @see #headerWithName(String)
 	 */
-	public static Snippet responseHeaders(Map<String, Object> attributes,
+	public static ResponseHeadersSnippet responseHeaders(Map<String, Object> attributes,
 			HeaderDescriptor... descriptors) {
 		return new ResponseHeadersSnippet(Arrays.asList(descriptors), attributes);
 	}

spring-restdocs-core/src/main/java/org/springframework/restdocs/headers/RequestHeadersSnippet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -16,6 +16,8 @@
 
 package org.springframework.restdocs.headers;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -27,6 +29,7 @@ import org.springframework.restdocs.snippet.Snippet;
  * A {@link Snippet} that documents the headers in a request.
  *
  * @author Andreas Evers
+ * @author Andy Wilkinson
  * @see HeaderDocumentation#requestHeaders(HeaderDescriptor...)
  * @see HeaderDocumentation#requestHeaders(Map, HeaderDescriptor...)
  */
@@ -60,4 +63,18 @@ public class RequestHeadersSnippet extends AbstractHeadersSnippet {
 		return operation.getRequest().getHeaders().keySet();
 	}
 
+	/**
+	 * Returns a new {@code RequestHeadersSnippet} configured with this snippet's
+	 * attributes and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public RequestHeadersSnippet and(HeaderDescriptor... additionalDescriptors) {
+		List<HeaderDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(this.getHeaderDescriptors());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new RequestHeadersSnippet(combinedDescriptors, getAttributes());
+	}
+
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/headers/ResponseHeadersSnippet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -16,6 +16,8 @@
 
 package org.springframework.restdocs.headers;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -27,6 +29,7 @@ import org.springframework.restdocs.snippet.Snippet;
  * A {@link Snippet} that documents the headers in a response.
  *
  * @author Andreas Evers
+ * @author Andy Wilkinson
  * @see HeaderDocumentation#responseHeaders(HeaderDescriptor...)
  * @see HeaderDocumentation#responseHeaders(Map, HeaderDescriptor...)
  */
@@ -60,4 +63,18 @@ public class ResponseHeadersSnippet extends AbstractHeadersSnippet {
 		return operation.getResponse().getHeaders().keySet();
 	}
 
+	/**
+	 * Returns a new {@code ResponseHeadersSnippet} configured with this snippet's
+	 * attributes and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public final ResponseHeadersSnippet and(HeaderDescriptor... additionalDescriptors) {
+		List<HeaderDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(this.getHeaderDescriptors());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new ResponseHeadersSnippet(combinedDescriptors, getAttributes());
+	}
+
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/http/HttpDocumentation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -18,8 +18,6 @@ package org.springframework.restdocs.http;
 
 import java.util.Map;
 
-import org.springframework.restdocs.snippet.Snippet;
-
 /**
  * Static factory methods for documenting a RESTful API's HTTP requests.
  *
@@ -38,7 +36,7 @@ public abstract class HttpDocumentation {
 	 *
 	 * @return the snippet that will document the HTTP request
 	 */
-	public static Snippet httpRequest() {
+	public static HttpRequestSnippet httpRequest() {
 		return new HttpRequestSnippet();
 	}
 
@@ -50,7 +48,7 @@ public abstract class HttpDocumentation {
 	 * @param attributes the attributes
 	 * @return the snippet that will document the HTTP request
 	 */
-	public static Snippet httpRequest(Map<String, Object> attributes) {
+	public static HttpRequestSnippet httpRequest(Map<String, Object> attributes) {
 		return new HttpRequestSnippet(attributes);
 	}
 
@@ -60,7 +58,7 @@ public abstract class HttpDocumentation {
 	 *
 	 * @return the snippet that will document the HTTP response
 	 */
-	public static Snippet httpResponse() {
+	public static HttpResponseSnippet httpResponse() {
 		return new HttpResponseSnippet();
 	}
 
@@ -72,7 +70,7 @@ public abstract class HttpDocumentation {
 	 * @param attributes the attributes
 	 * @return the snippet that will document the HTTP response
 	 */
-	public static Snippet httpResponse(Map<String, Object> attributes) {
+	public static HttpResponseSnippet httpResponse(Map<String, Object> attributes) {
 		return new HttpResponseSnippet(attributes);
 	}
 

spring-restdocs-core/src/main/java/org/springframework/restdocs/hypermedia/HypermediaDocumentation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -19,8 +19,6 @@ package org.springframework.restdocs.hypermedia;
 import java.util.Arrays;
 import java.util.Map;
 
-import org.springframework.restdocs.snippet.Snippet;
-
 /**
  * Static factory methods for documenting a RESTful API that utilizes Hypermedia.
  *
@@ -59,7 +57,7 @@ public abstract class HypermediaDocumentation {
 	 * @param descriptors the descriptions of the response's links
 	 * @return the snippet that will document the links
 	 */
-	public static Snippet links(LinkDescriptor... descriptors) {
+	public static LinksSnippet links(LinkDescriptor... descriptors) {
 		return new LinksSnippet(new ContentTypeLinkExtractor(),
 				Arrays.asList(descriptors));
 	}
@@ -83,7 +81,7 @@ public abstract class HypermediaDocumentation {
 	 * @param descriptors the descriptions of the response's links
 	 * @return the snippet that will document the links
 	 */
-	public static Snippet links(Map<String, Object> attributes,
+	public static LinksSnippet links(Map<String, Object> attributes,
 			LinkDescriptor... descriptors) {
 		return new LinksSnippet(new ContentTypeLinkExtractor(),
 				Arrays.asList(descriptors), attributes);
@@ -107,7 +105,7 @@ public abstract class HypermediaDocumentation {
 	 * @param descriptors the descriptions of the response's links
 	 * @return the snippet that will document the links
 	 */
-	public static Snippet links(LinkExtractor linkExtractor,
+	public static LinksSnippet links(LinkExtractor linkExtractor,
 			LinkDescriptor... descriptors) {
 		return new LinksSnippet(linkExtractor, Arrays.asList(descriptors));
 	}
@@ -132,7 +130,7 @@ public abstract class HypermediaDocumentation {
 	 * @param descriptors the descriptions of the response's links
 	 * @return the snippet that will document the links
 	 */
-	public static Snippet links(LinkExtractor linkExtractor,
+	public static LinksSnippet links(LinkExtractor linkExtractor,
 			Map<String, Object> attributes, LinkDescriptor... descriptors) {
 		return new LinksSnippet(linkExtractor, Arrays.asList(descriptors), attributes);
 	}

spring-restdocs-core/src/main/java/org/springframework/restdocs/hypermedia/LinksSnippet.java

@@ -18,6 +18,7 @@ package org.springframework.restdocs.hypermedia;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
@@ -170,4 +171,18 @@ public class LinksSnippet extends TemplatedSnippet {
 		return model;
 	}
 
+	/**
+	 * Returns a new {@code RequestHeadersSnippet} configured with this snippet's link
+	 * extractor and attributes, and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public LinksSnippet and(LinkDescriptor... additionalDescriptors) {
+		List<LinkDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(this.descriptorsByRel.values());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new LinksSnippet(this.linkExtractor, combinedDescriptors, getAttributes());
+	}
+
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/payload/PayloadDocumentation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -19,8 +19,6 @@ package org.springframework.restdocs.payload;
 import java.util.Arrays;
 import java.util.Map;
 
-import org.springframework.restdocs.snippet.Snippet;
-
 /**
  * Static factory methods for documenting a RESTful API's request and response payloads.
  *
@@ -117,7 +115,7 @@ public abstract class PayloadDocumentation {
 	 * @return the snippet that will document the fields
 	 * @see #fieldWithPath(String)
 	 */
-	public static Snippet requestFields(FieldDescriptor... descriptors) {
+	public static RequestFieldsSnippet requestFields(FieldDescriptor... descriptors) {
 		return new RequestFieldsSnippet(Arrays.asList(descriptors));
 	}
 
@@ -142,7 +140,7 @@ public abstract class PayloadDocumentation {
 	 * @return the snippet that will document the fields
 	 * @see #fieldWithPath(String)
 	 */
-	public static Snippet requestFields(Map<String, Object> attributes,
+	public static RequestFieldsSnippet requestFields(Map<String, Object> attributes,
 			FieldDescriptor... descriptors) {
 		return new RequestFieldsSnippet(Arrays.asList(descriptors), attributes);
 	}
@@ -167,7 +165,7 @@ public abstract class PayloadDocumentation {
 	 * @return the snippet that will document the fields
 	 * @see #fieldWithPath(String)
 	 */
-	public static Snippet responseFields(FieldDescriptor... descriptors) {
+	public static ResponseFieldsSnippet responseFields(FieldDescriptor... descriptors) {
 		return new ResponseFieldsSnippet(Arrays.asList(descriptors));
 	}
 
@@ -192,7 +190,7 @@ public abstract class PayloadDocumentation {
 	 * @return the snippet that will document the fields
 	 * @see #fieldWithPath(String)
 	 */
-	public static Snippet responseFields(Map<String, Object> attributes,
+	public static ResponseFieldsSnippet responseFields(Map<String, Object> attributes,
 			FieldDescriptor... descriptors) {
 		return new ResponseFieldsSnippet(Arrays.asList(descriptors), attributes);
 	}

spring-restdocs-core/src/main/java/org/springframework/restdocs/payload/RequestFieldsSnippet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -17,6 +17,8 @@
 package org.springframework.restdocs.payload;
 
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
@@ -66,4 +68,18 @@ public class RequestFieldsSnippet extends AbstractFieldsSnippet {
 		return operation.getRequest().getContent();
 	}
 
+	/**
+	 * Returns a new {@code RequestFieldsSnippet} configured with this snippet's
+	 * attributes and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public RequestFieldsSnippet and(FieldDescriptor... additionalDescriptors) {
+		List<FieldDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(getFieldDescriptors());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new RequestFieldsSnippet(combinedDescriptors, this.getAttributes());
+	}
+
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/payload/ResponseFieldsSnippet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 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.
@@ -17,6 +17,8 @@
 package org.springframework.restdocs.payload;
 
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
@@ -66,4 +68,18 @@ public class ResponseFieldsSnippet extends AbstractFieldsSnippet {
 		return operation.getResponse().getContent();
 	}
 
+	/**
+	 * Returns a new {@code ResponseFieldsSnippet} configured with this snippet's
+	 * attributes and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public ResponseFieldsSnippet and(FieldDescriptor... additionalDescriptors) {
+		List<FieldDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(getFieldDescriptors());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new ResponseFieldsSnippet(combinedDescriptors, this.getAttributes());
+	}
+
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/request/AbstractParametersSnippet.java

@@ -122,11 +122,24 @@ public abstract class AbstractParametersSnippet extends TemplatedSnippet {
 	 * {@link ParameterDescriptor#getName()}.
 	 *
 	 * @return the map of path descriptors
+	 * @deprecated since 1.1.0 in favor of {@link #getParameterDescriptors()}
 	 */
+	@Deprecated
 	protected final Map<String, ParameterDescriptor> getFieldDescriptors() {
 		return this.descriptorsByName;
 	}
 
+	/**
+	 * Returns a {@code Map} of {@link ParameterDescriptor ParameterDescriptors} that will
+	 * be used to generate the documentation key by their
+	 * {@link ParameterDescriptor#getName()}.
+	 *
+	 * @return the map of path descriptors
+	 */
+	protected final Map<String, ParameterDescriptor> getParameterDescriptors() {
+		return this.descriptorsByName;
+	}
+
 	/**
 	 * Returns a model for the given {@code descriptor}.
 	 *

spring-restdocs-core/src/main/java/org/springframework/restdocs/request/PathParametersSnippet.java

@@ -16,6 +16,8 @@
 
 package org.springframework.restdocs.request;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
@@ -122,4 +124,18 @@ public class PathParametersSnippet extends AbstractParametersSnippet {
 		throw new SnippetException(message);
 	}
 
+	/**
+	 * Returns a new {@code PathParametersSnippet} configured with this snippet's
+	 * attributes and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public PathParametersSnippet and(ParameterDescriptor... additionalDescriptors) {
+		List<ParameterDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(getParameterDescriptors().values());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new PathParametersSnippet(combinedDescriptors, this.getAttributes());
+	}
+
 }

spring-restdocs-core/src/main/java/org/springframework/restdocs/request/RequestDocumentation.java

@@ -20,7 +20,6 @@ import java.util.Arrays;
 import java.util.Map;
 
 import org.springframework.restdocs.operation.OperationRequest;
-import org.springframework.restdocs.snippet.Snippet;
 
 /**
  * Static factory methods for documenting aspects of a request sent to a RESTful API.
@@ -61,7 +60,8 @@ public abstract class RequestDocumentation {
 	 * @param descriptors the descriptions of the parameters in the request's path
 	 * @return the snippet that will document the parameters
 	 */
-	public static Snippet pathParameters(ParameterDescriptor... descriptors) {
+	public static PathParametersSnippet pathParameters(
+			ParameterDescriptor... descriptors) {
 		return new PathParametersSnippet(Arrays.asList(descriptors));
 	}
 
@@ -84,7 +84,7 @@ public abstract class RequestDocumentation {
 	 * @param descriptors the descriptions of the parameters in the request's path
 	 * @return the snippet that will document the parameters
 	 */
-	public static Snippet pathParameters(Map<String, Object> attributes,
+	public static PathParametersSnippet pathParameters(Map<String, Object> attributes,
 			ParameterDescriptor... descriptors) {
 		return new PathParametersSnippet(Arrays.asList(descriptors), attributes);
 	}
@@ -107,7 +107,8 @@ public abstract class RequestDocumentation {
 	 * @return the snippet
 	 * @see OperationRequest#getParameters()
 	 */
-	public static Snippet requestParameters(ParameterDescriptor... descriptors) {
+	public static RequestParametersSnippet requestParameters(
+			ParameterDescriptor... descriptors) {
 		return new RequestParametersSnippet(Arrays.asList(descriptors));
 	}
 
@@ -131,8 +132,8 @@ public abstract class RequestDocumentation {
 	 * @return the snippet that will document the parameters
 	 * @see OperationRequest#getParameters()
 	 */
-	public static Snippet requestParameters(Map<String, Object> attributes,
-			ParameterDescriptor... descriptors) {
+	public static RequestParametersSnippet requestParameters(
+			Map<String, Object> attributes, ParameterDescriptor... descriptors) {
 		return new RequestParametersSnippet(Arrays.asList(descriptors), attributes);
 	}
 

spring-restdocs-core/src/main/java/org/springframework/restdocs/request/RequestParametersSnippet.java

@@ -16,6 +16,8 @@
 
 package org.springframework.restdocs.request;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -84,4 +86,18 @@ public class RequestParametersSnippet extends AbstractParametersSnippet {
 		return operation.getRequest().getParameters().keySet();
 	}
 
+	/**
+	 * Returns a new {@code RequestParametersSnippet} configured with this snippet's
+	 * attributes and its descriptors combined with the given
+	 * {@code additionalDescriptors}.
+	 * @param additionalDescriptors the additional descriptors
+	 * @return the new snippet
+	 */
+	public RequestParametersSnippet and(ParameterDescriptor... additionalDescriptors) {
+		List<ParameterDescriptor> combinedDescriptors = new ArrayList<>();
+		combinedDescriptors.addAll(getParameterDescriptors().values());
+		combinedDescriptors.addAll(Arrays.asList(additionalDescriptors));
+		return new RequestParametersSnippet(combinedDescriptors, this.getAttributes());
+	}
+
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/headers/RequestHeadersSnippetTests.java

@@ -143,4 +143,27 @@ public class RequestHeadersSnippetTests extends AbstractSnippetTests {
 										.header("Accept", "*/*").build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectRequestHeaders("additional-descriptors")
+				.withContents(tableWithHeader("Name", "Description").row("X-Test", "one")
+						.row("Accept", "two").row("Accept-Encoding", "three")
+						.row("Accept-Language", "four").row("Cache-Control", "five")
+						.row("Connection", "six"));
+		HeaderDocumentation
+				.requestHeaders(headerWithName("X-Test").description("one"),
+						headerWithName("Accept").description("two"),
+						headerWithName("Accept-Encoding").description("three"),
+						headerWithName("Accept-Language").description("four"))
+				.and(headerWithName("Cache-Control").description("five"),
+						headerWithName("Connection").description("six"))
+				.document(operationBuilder("additional-descriptors")
+						.request("http://localhost").header("X-Test", "test")
+						.header("Accept", "*/*")
+						.header("Accept-Encoding", "gzip, deflate")
+						.header("Accept-Language", "en-US,en;q=0.5")
+						.header("Cache-Control", "max-age=0")
+						.header("Connection", "keep-alive").build());
+	}
+
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/headers/ResponseHeadersSnippetTests.java

@@ -133,4 +133,25 @@ public class ResponseHeadersSnippetTests extends AbstractSnippetTests {
 										.header("Etag", "lskjadldj3ii32l2ij23").build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectResponseHeaders("additional-descriptors")
+				.withContents(tableWithHeader("Name", "Description").row("X-Test", "one")
+						.row("Content-Type", "two").row("Etag", "three")
+						.row("Cache-Control", "five").row("Vary", "six"));
+		HeaderDocumentation
+				.responseHeaders(headerWithName("X-Test").description("one"),
+						headerWithName("Content-Type").description("two"),
+						headerWithName("Etag").description("three"))
+				.and(headerWithName("Cache-Control").description("five"),
+						headerWithName("Vary")
+								.description("six"))
+				.document(operationBuilder("additional-descriptors").response()
+						.header("X-Test", "test")
+						.header("Content-Type", "application/json")
+						.header("Etag", "lskjadldj3ii32l2ij23")
+						.header("Cache-Control", "max-age=0").header("Vary", "User-Agent")
+						.build());
+	}
+
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/hypermedia/LinksSnippetTests.java

@@ -132,4 +132,16 @@ public class LinksSnippetTests extends AbstractSnippetTests {
 												.build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectLinks("additional-descriptors")
+				.withContents(tableWithHeader("Relation", "Description").row("a", "one")
+						.row("b", "two"));
+		HypermediaDocumentation
+				.links(new StubLinkExtractor().withLinks(new Link("a", "alpha"),
+						new Link("b", "bravo")),
+				new LinkDescriptor("a").description("one"))
+				.and(new LinkDescriptor("b").description("two"))
+				.document(operationBuilder("additional-descriptors").build());
+	}
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/payload/RequestFieldsSnippetTests.java

@@ -160,4 +160,20 @@ public class RequestFieldsSnippetTests extends AbstractSnippetTests {
 								.build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectRequestFields("additional-descriptors")
+				.withContents(tableWithHeader("Path", "Type", "Description")
+						.row("a.b", "Number", "one").row("a.c", "String", "two")
+						.row("a", "Object", "three"));
+
+		PayloadDocumentation
+				.requestFields(fieldWithPath("a.b").description("one"),
+						fieldWithPath("a.c").description("two"))
+				.and(fieldWithPath("a").description("three"))
+				.document(operationBuilder("additional-descriptors")
+						.request("http://localhost")
+						.content("{\"a\": {\"b\": 5, \"c\": \"charlie\"}}").build());
+	}
+
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/payload/ResponseFieldsSnippetTests.java

@@ -211,4 +211,25 @@ public class ResponseFieldsSnippetTests extends AbstractSnippetTests {
 								.build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectResponseFields("additional-descriptors")
+				.withContents(tableWithHeader("Path", "Type", "Description")
+						.row("id", "Number", "one").row("date", "String", "two")
+						.row("assets", "Array", "three").row("assets[]", "Object", "four")
+						.row("assets[].id", "Number", "five")
+						.row("assets[].name", "String", "six"));
+		PayloadDocumentation
+				.responseFields(fieldWithPath("id").description("one"),
+						fieldWithPath("date").description("two"),
+						fieldWithPath("assets").description("three"))
+				.and(fieldWithPath("assets[]").description("four"),
+						fieldWithPath("assets[].id").description("five"),
+						fieldWithPath("assets[].name").description("six"))
+				.document(operationBuilder("additional-descriptors").response()
+						.content("{\"id\": 67,\"date\": \"2015-01-20\",\"assets\":"
+								+ " [{\"id\":356,\"name\": \"sample\"}]}")
+						.build());
+	}
+
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/request/PathParametersSnippetTests.java

@@ -133,6 +133,19 @@ public class PathParametersSnippetTests extends AbstractSnippetTests {
 										.build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectPathParameters("additional-descriptors").withContents(
+				tableWithTitleAndHeader(getTitle(), "Parameter", "Description")
+						.row("a", "one").row("b", "two"));
+		RequestDocumentation.pathParameters(parameterWithName("a").description("one"))
+				.and(parameterWithName("b").description("two"))
+				.document(operationBuilder("additional-descriptors")
+						.attribute(RestDocumentationGenerator.ATTRIBUTE_NAME_URL_TEMPLATE,
+								"/{a}/{b}")
+						.build());
+	}
+
 	private String getTitle() {
 		return this.templateFormat == TemplateFormats.asciidoctor() ? "/{a}/{b}"
 				: "`/{a}/{b}`";

spring-restdocs-core/src/test/java/org/springframework/restdocs/request/RequestParametersSnippetTests.java

@@ -128,4 +128,16 @@ public class RequestParametersSnippetTests extends AbstractSnippetTests {
 												.build());
 	}
 
+	@Test
+	public void additionalDescriptors() throws IOException {
+		this.snippet.expectRequestParameters("additional-descriptors")
+				.withContents(tableWithHeader("Parameter", "Description").row("a", "one")
+						.row("b", "two"));
+		RequestDocumentation.requestParameters(parameterWithName("a").description("one"))
+				.and(parameterWithName("b").description("two"))
+				.document(operationBuilder("additional-descriptors")
+						.request("http://localhost").param("a", "bravo")
+						.param("b", "bravo").build());
+	}
+
 }