Function flat_params_to_def

crates/openshell-policy/src/lib.rs:425–444

Convert flat runtime params back to YAML. MCP gets readable nested params when the flat keys can be losslessly split. Non-MCP protocols keep flat keys only for lossless serialization; generic JSON-RPC validation rejects params matchers before enforcement.

(
    protocol: &str,
    params: BTreeMap<String, QueryMatcherDef>,
)

// only for lossless serialization; generic JSON-RPC validation rejects params
// matchers before enforcement.
fn flat_params_to_def(
    protocol: &str,
    params: BTreeMap<String, QueryMatcherDef>,
) -> BTreeMap<String, ParamMatcherDef> {
    let flat = params.into_iter().collect::<Vec<_>>();
    // MCP uses nested YAML for readability. Non-MCP protocols keep the flat
    // form for lossless serialization of existing proto data only.
    if !is_mcp_protocol(protocol) {
        return flat_param_matchers_to_def(flat);
    }

    let mut nested = BTreeMap::new();
    for (key, matcher) in &flat {
        if insert_nested_param(&mut nested, key, ParamMatcherDef::Matcher(matcher.clone())).is_err()
        {
            return flat_param_matchers_to_def(flat);
        }
    }
    nested
}

fn flat_param_matchers_to_def(
    params: Vec<(String, QueryMatcherDef)>,