# How to Use

> **People find DSLs valuable because a well-designed DSL can be much easier to program with than a traditional library. This improves programmer productivity, which is always valuable.**
>
> Martin Fowler

### The Skrape{it} DSL$$\_1$$ is the recommended way of using the library. It offers the highest level of features and usability.

The DSL should be nearly self-explaining. Depending on your use-case here is an example with explanations on how to use skrape{it} to write automated tests that validates an endpoint or an URL that is returning HTML:

```kotlin
class CompleteSkrapeItExampleTest {
    
@Test
internal fun `dsl can skrape by url`() {
    skrape {
        request { // configure the fetcher aka http clients request
            url = "http://localhost:8080/example"
            method = GET // optional -> defaults to GET
            timeout = 5000 // optional -> defaults to 5000ms
            followRedirects = true // optional -> defaults to true
            userAgent = "some custom user agent" // optional -> defaults to "Mozilla/5.0 skrape.it"
            cookies = mapOf("some-cookie-name" to "some-value") // optional
            headers = mapOf("some-custom-header" to "some-value") // optional
        }
        
        extract { // execute the request and invoke its results
            
            htmlDocument { // parse the response body to a skrape it Doc object
                // all offical html and html5 elements are supported by the DSL
                div {
                    withClass = "foo" and "bar" and "fizz" and "buzz"
                    withAttribute = "some-key" to "some-value"
                    // will create css-query div.foo.bar.fizz.buzz[some-key='some-value']
                    
                    findFirst { // will find the first matching occurence 
                        text toBe "div with class foo"
                    }

                    findAll { // will find the all matching occurences
                        toBePresentExactlyOnce()
                    }
                }
                // can handle custom tags as well
                "a-custom-tag" {
                    findFirst {
                        text toBe "i'm a custom html5 tag"
                    }
                }
                // can handle custom tags written in css selctor query syntax
                "div.foo.bar.fizz.buzz" {
                    findFirst {
                        text toBe "div with class foo"
                    }
                }

                // can handle custom tags and add selector specificas via DSL
                "div.foo" {

                    withClass = "bar" and "fizz" and "buzz"

                    findFirst {
                        text toBe "div with class foo"
                    }
                }
            }
        }
    }
}
}
```

To learn more about the possible request-options please have a look here:

{% content-ref url="http-client/request-options" %}
[request-options](https://docs.skrape.it/docs/http-client/request-options)
{% endcontent-ref %}

To learn more about the parsing html and working with elements please have a look here:

{% content-ref url="parser/parsing-html" %}
[parsing-html](https://docs.skrape.it/docs/parser/parsing-html)
{% endcontent-ref %}

To learn more about the build-in matchers please have a look here:

{% content-ref url="broken-reference" %}
[Broken link](https://docs.skrape.it/docs/broken-reference)
{% endcontent-ref %}

Further Testing Example:

{% content-ref url="dsl/basic-test-scenario" %}
[basic-test-scenario](https://docs.skrape.it/docs/dsl/basic-test-scenario)
{% endcontent-ref %}

Further information on what is the best way to actually scrape the content of an webpage and work with that data can be found here:

{% content-ref url="dsl/extracting-data-from-websites" %}
[extracting-data-from-websites](https://docs.skrape.it/docs/dsl/extracting-data-from-websites)
{% endcontent-ref %}

####

* > $$1)$$ A [**domain-specific language** (**DSL**)](https://en.wikipedia.org/wiki/Domain-specific_language) is a computer language specialized to a particular application domain.