Add support for modifying a request prior to it being documented

Prior to this commit it was not possible to modify a request prior to
it being documented, only a response. This commit builds on the new
Operation abstraction to simplify the existing response modification
support and to add support for request modification.

Closes gh-84

docs/src/docs/asciidoc/customizing-requests-and-responses.adoc

@@ -0,0 +1,56 @@
+[[customizing-requests-and-responses]]
+== Customizing requests and responses
+
+There may be situations where you do not want to document a request exactly as it was sent
+or a response exactly as it was received. Spring REST Docs provides a number of
+preprocessors that can be used to modify a request or response before it's documented.
+
+Preprocessing is configured by calling `document` with an `OperationRequestPreprocessor`,
+and/or an `OperationResponsePreprocessor`. Instances can be obtained using the
+static `preprocessRequest` and `preprocessResponse` methods on `Preprocessors`:
+
+[source,java,indent=0]
+----
+include::{examples-dir}/com/example/Preprocessing.java[tags=general]
+----
+<1> Apply a request preprocessor that will remove the header named `Foo`.
+<2> Apply a response preprocessor that will pretty print its content.
+
+Various built in preprocessors, including those illustrated above, are available via the
+static methods on `Preprocessors`. See below for further details.
+
+
+
+[[customizing-requests-and-responses-pretty-printing]]
+=== Pretty printing
+
+`prettyPrint` on `Preprocessors` formats the content of the request or response
+to make it easier to read.
+
+
+
+[[customizing-requests-and-responses-masking-links]]
+=== Masking links
+
+If you're documenting a Hypermedia-based API, you may want to encourage clients to
+navigate the API using links rather than through the use of hard coded URIs. One way to do
+this is to limit the use of URIs in the documentation. `maskLinks` on
+`Preprocessors` replaces the `href` of any links in the response with `...`. A
+different replacement can also be specified if you wish.
+
+
+
+[[customizing-requests-and-responses-removing-headers]]
+=== Removing headers
+
+`removeHeaders` on `Preprocessors` removes any occurrences of the named headers
+from the request or response.
+
+
+
+[[customizing-requests-and-responses-replacing-patterns]]
+=== Replacing patterns
+
+`replacePattern` on `Preprocessors` provides a general purpose mechanism for
+replacing content in a request or response. Any occurrences of a regular expression are
+replaced.

docs/src/docs/asciidoc/customizing-responses.adoc

@@ -1,45 +0,0 @@
-[[customizing-responses]]
-== Customizing responses
-
-There may be situations where you do not want to document a response exactly as received.
-Spring REST Docs provides a number of response post processors that can be used to modify
-a response after it is received but before it's documented.
-
-Response modification is configured using a `ResponseModifier`. An instance can be
-obtained using the static `modifyResponseTo` method on `RestDocumentation`. Once the
-response modifications have been provided, documentation can be configured as usual
-via the `andDocument` method:
-
-[source,java,indent=0]
-----
-include::{examples-dir}/com/example/ResponsePostProcessing.java[tags=general]
-----
-<1> Call `modifyResponseTo` to configure response modifications, passing in one or more
-`ResponsePostProcessor` implementations.
-<2> Proceed with documenting the call.
-
-
-[[customizing-responses-pretty-printing]]
-=== Pretty printing
-
-`prettyPrintContent` on `ResponsePostProcessors` formats the body of the response to
-make it easier to read.
-
-[[customizing-responses-masking-links]]
-=== Masking links
-
-If you're documenting a Hypermedia-based API, you may want to encourage clients to
-navigate the API using links rather than through the use of hard coded URIs. One way to do
-this is to limit the use of URIs in the documentation. `maskLinks` on
-`ResponsePostProcessors` replaces the `href` of any links in the response with `...`. A
-different replacement can also be specified if you wish.
-
-=== Removing headers
-
-`removeHeaders` on `ResponsePostProcessors` removes any occurrences of the named headers
-from the response.
-
-=== Replacing patterns
-
-`replacePattern` on `ResponsePostProcessors` provides a general purpose mechanism for
-replacing content in a response. Any occurrences of a regular expression are replaced.

docs/src/docs/asciidoc/index.adoc

@@ -23,7 +23,7 @@ snippets produced with Spring MVC Test.
 include::introduction.adoc[]
 include::getting-started.adoc[]
 include::documenting-your-api.adoc[]
-include::customizing-responses.adoc[]
+include::customizing-requests-and-responses.adoc[]
 include::configuration.adoc[]
 include::working-with-asciidoctor.adoc[]
 include::contributing.adoc[]

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

@@ -16,13 +16,17 @@
 
 package com.example;
 
-import static org.springframework.restdocs.RestDocumentation.modifyResponseTo;
 import static org.springframework.restdocs.RestDocumentationRequestBuilders.get;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import static org.springframework.restdocs.operation.preprocess.Preprocessors.preprocessRequest;
+import static org.springframework.restdocs.operation.preprocess.Preprocessors.preprocessResponse;
+import static org.springframework.restdocs.operation.preprocess.Preprocessors.removeHeaders;
+import static org.springframework.restdocs.operation.preprocess.Preprocessors.prettyPrint;
+import static org.springframework.restdocs.RestDocumentation.document;
 
 import org.springframework.test.web.servlet.MockMvc;
 
-public class ResponsePostProcessing {
+public class Preprocessing {
 
 	private MockMvc mockMvc;
 
@@ -30,8 +34,9 @@ public class ResponsePostProcessing {
 		// tag::general[]
 		this.mockMvc.perform(get("/"))
 			.andExpect(status().isOk())
-			.andDo(modifyResponseTo(/* ... */) // <1>
-					.andDocument("index")); // <2>
+			.andDo(document("index",
+					preprocessRequest(removeHeaders("Foo")), // <1>
+					preprocessResponse(prettyPrint()))); // <2>
 		// end::general[]
 	}