add extractors info to guide

guide/src/qs_5.md

@@ -329,9 +329,7 @@ It uses *serde* package as a deserialization library.
 has to implement *serde's *`Deserialize` trait.
 
 ```rust
-# extern crate bytes;
 # extern crate actix_web;
-# extern crate futures;
 #[macro_use] extern crate serde_derive;
 use actix_web::{App, Path, Result, http::Method};
 
@@ -352,6 +350,27 @@ fn main() {
 }
 ```
 
+It also possible to extract path information to a tuple, in this case you don't need
+to define extra type, just use tuple for as a `Path` generic type.
+
+Here is previous example re-written using tuple instead of specific type.
+
+```rust
+# extern crate actix_web;
+use actix_web::{App, Path, Result, http::Method};
+
+// extract path info using serde
+fn index(info: Path<(String, u32)>) -> Result<String> {
+    Ok(format!("Welcome {}! id: {}", info.0, info.1))
+}
+
+fn main() {
+    let app = App::new()
+        .resource("/{username}/{id}/index.html",    // <- define path parameters
+                  |r| r.method(Method::GET).with(index));
+}
+```
+
 [Query](../actix_web/struct.Query.html) provides similar functionality for
 request query parameters.
 

guide/src/qs_7.md

@@ -58,9 +58,36 @@ fn index(req: HttpRequest) -> HttpResponse {
 
 ## JSON Request
 
-There are two options for json body deserialization.
+There are several options for json body deserialization.
 
-The first option is to use *HttpResponse::json()*. This method returns a
+The first option is to use *Json* extractor. You define handler function
+that accepts `Json<T>` as a parameter and use `.with()` method for registering
+this handler. It is also possible to accept arbitrary valid json object by
+using `serde_json::Value` as a type `T`
+
+```rust
+# extern crate actix_web;
+#[macro_use] extern crate serde_derive;
+use actix_web::{App, Json, Result, http};
+
+#[derive(Deserialize)]
+struct Info {
+    username: String,
+}
+
+/// extract `Info` using serde
+fn index(info: Json<Info>) -> Result<String> {
+    Ok(format!("Welcome {}!", info.username))
+}
+
+fn main() {
+    let app = App::new().resource(
+       "/index.html",
+       |r| r.method(http::Method::POST).with(index));  // <- use `with` extractor
+}
+```
+
+The second option is to use *HttpResponse::json()*. This method returns a
 [*JsonBody*](../actix_web/dev/struct.JsonBody.html) object which resolves into
 the deserialized value.
 
@@ -128,7 +155,7 @@ A complete example for both options is available in
 
 ## JSON Response
 
-The `Json` type allows you to respond with well-formed JSON data: simply return a value of
+The `Json` type allows to respond with well-formed JSON data: simply return a value of
 type Json<T> where T is the type of a structure to serialize into *JSON*. The
 type `T` must implement the `Serialize` trait from *serde*.