fn parse_multipart_body_fields()

in src/azure/client.rs [397:444]

• 39 lines of code
• 7 McCabe index (conditional complexity)

fn parse_multipart_body_fields(body: Bytes, boundary: &[u8]) -> Result<Vec<MultipartField>> {
    let start_marker = [b"--", boundary, b"\r\n"].concat();
    let next_marker = &start_marker[..start_marker.len() - 2];
    let end_marker = [b"--", boundary, b"--\r\n"].concat();

    // There should be at most 256 responses per batch
    let mut fields = Vec::with_capacity(256);
    let mut remaining: &[u8] = body.as_ref();
    loop {
        remaining = remaining
            .strip_prefix(start_marker.as_slice())
            .ok_or_else(|| invalid_response("missing start marker for field"))?;

        // The documentation only mentions two headers for fields, we leave some extra margin
        let mut scratch = [httparse::EMPTY_HEADER; 10];
        let mut headers = HeaderMap::new();
        match httparse::parse_headers(remaining, &mut scratch) {
            Ok(httparse::Status::Complete((pos, headers_slice))) => {
                remaining = &remaining[pos..];
                for header in headers_slice {
                    headers.insert(
                        HeaderName::from_bytes(header.name.as_bytes()).expect("valid"),
                        HeaderValue::from_bytes(header.value).expect("valid"),
                    );
                }
            }
            _ => return Err(invalid_response("unable to parse field headers").into()),
        };

        let next_pos = remaining
            .windows(next_marker.len())
            .position(|window| window == next_marker)
            .ok_or_else(|| invalid_response("early EOF while seeking to next boundary"))?;

        fields.push(MultipartField {
            headers,
            content: body.slice_ref(&remaining[..next_pos]),
        });

        remaining = &remaining[next_pos..];

        // Support missing final CRLF
        if remaining == end_marker || remaining == &end_marker[..end_marker.len() - 2] {
            break;
        }
    }
    Ok(fields)
}