Hm.. Can not believe it is impossible to set custom headers for HTTP client :slightly_smiling_face: ...

# ktor

[anli]

Hm.. Can not believe it is impossible to set custom headers for HTTP client 🙂 I try elaborate my issue. So, I play with this code:

val response = client.call("some/url") {
        contentType(ContentType.Application.Json)
        method = <http://HttpMethod.Post|HttpMethod.Post>
        headers = HeadersBuilder ()
        body = data
    }

But compiler climes "Val can not be reassigned" against headers. So. how are you settings custom client headers?

[orangy]

@e5l

[e5l]

Consider to use clear instead of reassign headers

[anli]

@e5l Would you, please, be a little more elaborate? Say, I have got "Key1" to "Value1" and "Key2" to "Value2" pairs. How to add?

[Deactivated User]

You can use the header function:

val response = client.call(“some/url”) {
    contentType(ContentType.Application.Json)
    method = <http://HttpMethod.Post|HttpMethod.Post>
    headers.clear() // clear headers 
    header(“header”, “value”) // set one header
    headers { 
        header(“header”, “value”)
    }
    body = data
}

[e5l]

You could use header method, or add it by hand:

client.call {
    headers.append("Hello", "World")
    headers.append("Hello2", "World2")
}

[Deactivated User]

headers is val, because you mutate it. You can call headers.clear, or headers.append. But if you don’t care about other headers, you can just call header

Going to update the documentation with this

[anli]

@Deactivated User @e5l Thanks, am going to try!

[Deactivated User]

https://ktor.io/clients/http-client.html#custom-headers

[anli]

@Deactivated User O-o-o, excellent!!