class MainTest {
  @Test
  fun simple() {
    val request = fromArgs("http://example.com").createRequest()
    assertThat(request.method).isEqualTo("GET")
    assertThat(request.url.toString()).isEqualTo("http://example.com/")
    assertThat(request.body).isNull()
  }

  @Test
  @Throws(IOException::class)
  fun put() {
    val request = fromArgs("-X", "PUT", "-d", "foo", "http://example.com").createRequest()

---

But for this example, we'll use a very simple HTML document with some JavaScript, all inside a long string.

This, of course, is not optimal and you wouldn't use it for production.

In production you would have one of the options above.

But it's the simplest way to focus on the server-side of WebSockets and have a working example:

```Python hl_lines="2  6-38  41-43"

This is very useful when you need to:

* Have shared logic (the same code logic again and again).
* Share database connections.
* Enforce security, authentication, role requirements, etc.
* And many other things...

All these, while minimizing code repetition.

## First Steps

Let's see a very simple example. It will be so simple that it is not very useful, for now.

      CertificatePinner.Builder()
        .add("*.example.com", certA1Sha256Pin)
        .add("a.example.com", certB1Sha256Pin)
        .add("b.example.com", certC1Sha256Pin)
        .build()

    val expectedPins =
      listOf(
        Pin("*.example.com", certA1Sha256Pin),
        Pin("a.example.com", certB1Sha256Pin),
      )
    assertThat(certificatePinner.findMatchingPins("a.example.com")).isEqualTo(expectedPins)
  }

  @Test

state of the world. It is regenerated (usually partially) on each configuration push (more on this below). Due to being a snapshot, most lookups are lock-free.

`PushContext` is built up by querying the above layers. For some simple use cases, this is as simple as storing something like `configstore.List(SomeType)`; in this case, the only difference from directly exposing the configstore is to snapshot the current state. In other cases, some pre-computations and indexes are computed to make...

* `allow_origins` - A list of origins that should be permitted to make cross-origin requests. E.g. `['https://example.org', 'https://www.example.org']`. You can use `['*']` to allow any origin.
* `allow_origin_regex` - A regex string to match against origins that should be permitted to make cross-origin requests. e.g. `'https://.*\.example\.org'`.

And then you can set those same memory limits and requirements in your configurations for your container management system (for example in **Kubernetes**). That way it will be able to **replicate the containers** in the **available machines** taking into account the amount of memory needed by them, and the amount available in the machines in the cluster.

		Short:   "Validate Istio policy and rules files",
		Example: `  # Validate bookinfo-gateway.yaml
  istioctl validate -f samples/bookinfo/networking/bookinfo-gateway.yaml

  # Validate bookinfo-gateway.yaml with shorthand syntax
  istioctl v -f samples/bookinfo/networking/bookinfo-gateway.yaml

  # Validate all yaml files under samples/bookinfo/networking directory
  istioctl validate -f samples/bookinfo/networking

Interceptors
============

Interceptors are a powerful mechanism that can monitor, rewrite, and retry calls. Here's a simple interceptor that logs the outgoing request and the incoming response.

```java
class LoggingInterceptor implements Interceptor {
  @Override public Response intercept(Interceptor.Chain chain) throws IOException {
    Request request = chain.request();

    long t1 = System.nanoTime();

<img src="/img/tutorial/bigger-applications/image01.png">

## Include the same router multiple times with different `prefix`

You can also use `.include_router()` multiple times with the *same* router using different prefixes.

This could be useful, for example, to expose the same API under different prefixes, e.g. `/api/v1` and `/api/latest`.