[Question] : How to add a default header map to HttpClientBuilder?

[ansrivas]

Hi, thank you for your work in creating this project.

I am trying to inject a default HeaderMap in client builder. I saw that there is SetOpt implementation as well but no method in Configurable to append the headers.

How can I achieve something like this?

let mut headers = HeaderMap::new();
headers.insert(
  "X-header-something",
  HeaderValue::from_str("my-value").unwrap(),
);

let c = isahc::HttpClientBuilder::new()
    .set_default_headers(headers) // <---- Something like this
    .build()?;  

[sagebind]

Great question! This isn't currently possible, but its a great idea for a feature! I imagine it would look something like this:

impl HttpClientBuilder {
    // etc

    pub fn default_header(self, key: impl TryInto<HeaderName>, value: impl TryInto<HeaderValue>) -> Self {}

    pub fn default_headers_mut(&mut self) -> &mut HeaderMap<HeaderValue> {}
}

I saw that there is SetOpt implementation as well

That's just used as an internal helper for setting the headers provided in a Request given. Implementing default headers for a client would leverage the same code path.

[sagebind]

This feature is now available in 0.9.2! 🎉 Thanks to @ansrivas for implementing this!