Section IV - integrated testing

web-service-tests.rs

We now have one last step, which is to add a function that will provide the service object. This is will not be covered by unit testing and is instead should be covered by integrated testing.

To create integrated tests, first create a new file named web-service-tests.rs in a new directory named tests in the root path (same level as the src directory). Cargo will automatically parse the tests directory and run any tests that are located in any files located here.

.
|-- .git
|-- .gitignore
|-- src
     |-- bin
          |-- hello-world.rs
     |-- hello_world.rs
     |-- lib.rs
|-- tests
     | -- web-service-tests.rs
|-- Cargo.toml

In order to execute our service test, we will first need to include the actix-rt library to our project. We do this by adding the line actix-rt = "1.1" in the [dev-dependencies] section of the Cargo.toml file.

[dependencies]
log = "0.4"
env_logger = "0.8"
actix-web = "3"

[dev-dependencies]
actix-rt = "1.1"

Once the library has been included in the Manifest, we define which libraries are required in the web-service-tests module by adding the following lines at the top of the web-service-tests.rs file.

extern crate actix_web;

The extern declarations specify the dependent crates (or libraries) that will be used in the web-service-tests module.

We then declare the bindings (or shortcuts) to a resources that will be using in the web-service-tests module. This is done by adding the following use declarations below the extern crate declarations.

use myapp::hello_world;
use actix_web::{test, web, App};

Now we can add the code for our Hello World service test, which is added below the use declarations.

#[actix_rt::test]
async fn test_hello_world_ok() {

    let mut app = test::init_service(App::new().route("/", web::get().to(hello_world::index))).await;
    // create the request
    let req = test::TestRequest::with_header("content-type", "text/plain").to_request();
    // call the service
    let resp = test::call_service(&mut app, req).await;
    assert!(resp.status().is_success());

    // read response body
    let body = test::read_body(resp).await;
    assert_eq!(body, "Hello World!".to_string());
}

At this point the web-service-tests.rs file should look like this:

extern crate actix_web;

use myapp::hello_world;
use actix_web::{test, web, App};

#[actix_rt::test]
async fn test_hello_world_ok() {

    let mut app = test::init_service(App::new().route("/", web::get().to(hello_world::index))).await;
    // create the request
    let req = test::TestRequest::with_header("content-type", "text/plain").to_request();
    // call the service
    let resp = test::call_service(&mut app, req).await;
    assert!(resp.status().is_success());

    // read response body
    let body = test::read_body(resp).await;
    assert_eq!(body, "Hello World!".to_string());
}

Try running your test with the cargo test command. There should now be a line in the results referencing that the web_service_tests has run.

     Running target\debug\deps\web_service_tests-664800ae8a37eeb0.exe

running 1 test
test test_hello_world_ok ... ok