Method rewrite_basic_auth_token

crates/openshell-core/src/secrets.rs:409–433

Decode a Base64-encoded Basic auth token, resolve any placeholders in the decoded `username:password` string, and re-encode. Returns `None` if decoding fails or no placeholders are found.

(
        &self,
        encoded: &str,
    )

    ///
    /// Returns `None` if decoding fails or no placeholders are found.
    fn rewrite_basic_auth_token(
        &self,
        encoded: &str,
    ) -> Result<Option<String>, UnresolvedPlaceholderError> {
        let b64 = base64::engine::general_purpose::STANDARD;
        let Some(decoded_bytes) = b64.decode(encoded.trim()).ok() else {
            return Ok(None);
        };
        let Some(decoded) = std::str::from_utf8(&decoded_bytes).ok() else {
            return Ok(None);
        };

        if !contains_raw_reserved_marker(decoded) {
            return Ok(None);
        }

        let mut rewritten = decoded.to_string();
        let replacements = self.rewrite_text_placeholders(&mut rewritten, "header")?;

        if replacements == 0 {
            return Ok(None);
        }

        Ok(Some(b64.encode(rewritten.as_bytes())))
    }
}

fn alias_start_for_marker(text: &str, marker_abs: usize) -> usize {