Function fn_impl

codegen/src/func.rs:139–406

Generate function code.

(
    metadata: FnMetadata,
    item_stream: TokenStream,
    from_fn: bool,
)

/// Generate function code.
pub fn fn_impl(
    metadata: FnMetadata,
    item_stream: TokenStream,
    from_fn: bool,
) -> syn::Result<proc_macro2::TokenStream> {
    let url = metadata.url;
    let method = metadata.method.to_str();
    let meta_map = metadata.meta_map;

    let mut item_fn = syn::parse::<syn::ItemFn>(item_stream)?;
    let sig = &mut item_fn.sig;

    let mut config_keys = Vec::new();
    let mut config_values = Vec::new();
    for (k, v) in meta_map.iter() {
        let key = k.as_str();
        if from_fn == true && (key == "connect_timeout" || key == "read_timeout") {
            return Err(syn::Error::new_spanned(
                sig.fn_token,
                format!("`{}` is not support, please use custom config instead", key),
            ));
        }
        if !CONFIG_KEYS.contains(&k.as_str()) {
            continue;
        }
        config_keys.push(k);
        config_values.push(v);
    }

    let (header_keys, header_values) = match meta_map.get("headers") {
        Some(val) => parse_header_values(&val)?,
        None => (vec![], vec![]),
    };

    let asyncness = &sig.asyncness;
    if asyncness.is_none() {
        return Err(syn::Error::new_spanned(
            sig.fn_token,
            "only support async fn",
        ));
    }

    let vis = &item_fn.vis;
    let args = parse_args_from_sig(sig)?;

    let (param_names, param_vars) = find_type_name_vars(&args, ArgType::PARAM, |_fn_arg| true);

    let (path_names, path_vars) = find_type_name_vars(&args, ArgType::PATH, |_fn_arg| true);

    let (header_names, header_vars) =
        find_type_name_vars(&args, ArgType::HEADER, |fn_arg| !filter_struct(fn_arg));

    let (_header_struct_names, header_struct_vars) =
        find_type_name_vars(&args, ArgType::HEADER, |fn_arg| filter_struct(fn_arg));

    let (query_names, query_vars) = find_type_name_vars(&args, ArgType::QUERY, |fn_arg| {
        !filter_query_array(fn_arg) && !filter_struct(fn_arg)
    });