Trait HeaderProvider
pub trait HeaderProvider: Send + Sync {
// Required method
fn headers<'life0, 'async_trait>(
&'life0 self,
) -> Pin<Box<dyn Future<Output = Result<HashMap<String, String>, HeaderProviderError>> + Send + 'async_trait>>
where 'life0: 'async_trait,
Self: 'async_trait;
}