add testing section to guide

build.rs

@@ -20,6 +20,7 @@ fn main() {
               "guide/src/qs_4_5.md",
               "guide/src/qs_5.md",
               "guide/src/qs_7.md",
+              "guide/src/qs_8.md",
               "guide/src/qs_9.md",
               "guide/src/qs_10.md",
               "guide/src/qs_12.md",

guide/src/SUMMARY.md

@@ -8,6 +8,7 @@
 - [Errors](./qs_4_5.md)
 - [URL Dispatch](./qs_5.md)
 - [Request & Response](./qs_7.md)
+- [Testing](./qs_8.md)
 - [WebSockets](./qs_9.md)
 - [Middlewares](./qs_10.md)
 - [Static file handling](./qs_12.md)

guide/src/qs_8.md

@@ -0,0 +1,60 @@
+# Testing
+
+Every application should be well tested and. Actix provides the tools to perform unit and
+integration tests.
+
+## Integration tests
+
+There are several methods how you can test your application. Actix provides 
+[*TestServer*](../actix_web/test/struct.TestServer.html)
+server that could be used to run whole application of just specific handlers
+in real http server. At the moment it is required to use third-party libraries
+to make actual requests, libraries like [reqwest](https://crates.io/crates/reqwest).
+
+In simple form *TestServer* could be configured to use handler. *TestServer::new* method
+accepts configuration function, only argument for this function is *test application*
+instance. You can check [api documentation](../actix_web/test/struct.TestApp.html)
+for more information.
+
+```rust
+# extern crate actix_web;
+extern crate reqwest;
+use actix_web::*;
+use actix_web::test::TestServer;
+
+fn index(req: HttpRequest) -> HttpResponse {
+     httpcodes::HTTPOk.response()
+}
+
+fn main() {
+    let srv = TestServer::new(|app| app.handler(index));        // <- Start new test server
+    let url = srv.url("/");                                     // <- get handler url
+    assert!(reqwest::get(&url).unwrap().status().is_success()); // <- make request
+}
+```
+
+Other option is to use application factory. In this case you need to pass factory function
+same as you use for real http server configuration.
+
+```rust
+# extern crate actix_web;
+extern crate reqwest;
+use actix_web::*;
+use actix_web::test::TestServer;
+
+fn index(req: HttpRequest) -> HttpResponse {
+     httpcodes::HTTPOk.response()
+}
+
+/// This function get called by http server.
+fn create_app() -> Application {
+    Application::new()
+        .resource("/test", |r| r.h(index))
+}
+
+fn main() {
+    let srv = TestServer::with_factory(create_app);             // <- Start new test server
+    let url = srv.url("/test");                                 // <- get handler url
+    assert!(reqwest::get(&url).unwrap().status().is_success()); // <- make request
+}
+```