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StreamingBodyExt

Traitin experimentalfastly 0.13.1View source
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pub trait StreamingBodyExt {
    // Required methods
    fn append_trailer(
        &mut self,
        name: impl ToHeaderName,
        value: impl ToHeaderValue,
    );
    fn finish_with_trailers(self, trailers: &HeaderMap) -> Result<(), Error>;
}

Extensions to the crate::http::body::StreamingBody type to support trailers.

Methods

append_trailer

View source
fn append_trailer(&mut self, name: impl ToHeaderName, value: impl ToHeaderValue)

Append the given trailer name and value to this body.

Trailers will be sent once the body send is complete. This function will not discard any existing values for the trailer; this value will simply be appended to the set of existing values.

Stability

This is part of an experimental API that is subject to change or removal even in minor versions of this crate.

Parameters

self: &mut Self
name: impl ToHeaderName
value: impl ToHeaderValue

finish_with_trailers

View source
fn finish_with_trailers(self, trailers: &HeaderMap) -> Result<(), Error>

Get the trailers associated with this body.

Note that modifying this HeaderMap will have no effect on the trailers for the body; in order to add trailers, you will need to use BodyExt::append_trailer. If you need to remove a trailer, the only current mechanism to do so is to create a fresh body, and then copy over the trailers you wish to maintain. (If this inconvenient, please contact your Fastly support team, and mention this shortcoming.)

Trailers

Trailers can be tricky to access. You must completely read all bytes from the body before calling this function. The outermost Result reflects this requirement; if you receive BodyHandleError::TrailersNotReady, there are potentially more bytes available in the body that you must read.

Stability

This is part of an experimental API that is subject to change or removal even in minor versions of this crate.

Parameters

self: Self
trailers: &HeaderMap

Returns

Result<(), std::io::Error>
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