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Diffstat (limited to 'crates/service/service_macros/src/lib.rs')
-rw-r--r--crates/service/service_macros/src/lib.rs149
1 files changed, 0 insertions, 149 deletions
diff --git a/crates/service/service_macros/src/lib.rs b/crates/service/service_macros/src/lib.rs
deleted file mode 100644
index 2c2e4a8..0000000
--- a/crates/service/service_macros/src/lib.rs
+++ /dev/null
@@ -1,149 +0,0 @@
-use proc_macro::TokenStream;
-use quote::quote;
-use syn::{ItemFn, parse_macro_input};
-
-/// A procedural macro for generating structs that implement the Action trait
-///
-/// Usage:
-/// #[action_gen] or #[action_gen(local)]
-/// pub fn my_action(ctx: ActionContext, arg: MyArg) -> Result<MyReturn, TcpTargetError> {
-/// todo!()
-/// }
-#[proc_macro_attribute]
-pub fn action_gen(attr: TokenStream, item: TokenStream) -> TokenStream {
- let input_fn = parse_macro_input!(item as ItemFn);
- let is_local = if attr.is_empty() {
- false
- } else {
- let attr_str = attr.to_string();
- attr_str == "local" || attr_str.contains("local")
- };
-
- generate_action_struct(input_fn, is_local).into()
-}
-
-fn generate_action_struct(input_fn: ItemFn, _is_local: bool) -> proc_macro2::TokenStream {
- let fn_vis = &input_fn.vis;
- let fn_sig = &input_fn.sig;
- let fn_name = &fn_sig.ident;
- let fn_block = &input_fn.block;
-
- validate_function_signature(fn_sig);
-
- let (arg_type, return_type) = extract_types(fn_sig);
-
- let struct_name = quote::format_ident!("{}", convert_to_pascal_case(&fn_name.to_string()));
-
- let action_name_ident = &fn_name;
-
- quote! {
- #[derive(Debug, Clone, Default)]
- #fn_vis struct #struct_name;
-
- impl vcs_service::action::Action<#arg_type, #return_type> for #struct_name {
- fn action_name() -> &'static str {
- Box::leak(string_proc::snake_case!(stringify!(#action_name_ident)).into_boxed_str())
- }
-
- fn is_remote_action() -> bool {
- !#_is_local
- }
-
- async fn process(context: vcs_service::action::ActionContext, args: #arg_type) -> Result<#return_type, tcp_connection::error::TcpTargetError> {
- #fn_block
- }
- }
-
- #[deprecated = "This function is used by #[action_gen] as a template."]
- #[doc = " This function is used by #[action_gen] as a template to generate the struct. "]
- #[doc = " It is forbidden to call it anywhere."]
- #[doc = " You should use the generated struct to register this function in `ActionPool`"]
- #[doc = " and call it using the function name."]
- #fn_vis #fn_sig #fn_block
- }
-}
-
-fn validate_function_signature(fn_sig: &syn::Signature) {
- if !fn_sig.asyncness.is_some() {
- panic!("Expected async function for Action, but found synchronous function");
- }
-
- if fn_sig.inputs.len() != 2 {
- panic!(
- "Expected exactly 2 arguments for Action function: ctx: ActionContext and arg: T, but found {} arguments",
- fn_sig.inputs.len()
- );
- }
-
- let return_type = match &fn_sig.output {
- syn::ReturnType::Type(_, ty) => ty,
- _ => panic!(
- "Expected Action function to return Result<T, TcpTargetError>, but found no return type"
- ),
- };
-
- if let syn::Type::Path(type_path) = return_type.as_ref() {
- if let Some(segment) = type_path.path.segments.last() {
- if segment.ident != "Result" {
- panic!(
- "Expected Action function to return Result<T, TcpTargetError>, but found different return type"
- );
- }
- }
- } else {
- panic!(
- "Expected Action function to return Result<T, TcpTargetError>, but found no return type"
- );
- }
-}
-
-fn convert_to_pascal_case(s: &str) -> String {
- s.split('_')
- .map(|word| {
- let mut chars = word.chars();
- match chars.next() {
- None => String::new(),
- Some(first) => first.to_uppercase().collect::<String>() + chars.as_str(),
- }
- })
- .collect()
-}
-
-fn extract_types(fn_sig: &syn::Signature) -> (proc_macro2::TokenStream, proc_macro2::TokenStream) {
- let mut inputs = fn_sig.inputs.iter();
-
- let _ = inputs.next();
-
- let arg_type = match inputs.next() {
- Some(syn::FnArg::Typed(pat_type)) => {
- let ty = &pat_type.ty;
- quote::quote!(#ty)
- }
- _ => {
- panic!("Expected the second argument to be a typed parameter, but found something else")
- }
- };
-
- let return_type = match &fn_sig.output {
- syn::ReturnType::Type(_, ty) => {
- if let syn::Type::Path(type_path) = ty.as_ref() {
- if let syn::PathArguments::AngleBracketed(args) =
- &type_path.path.segments.last().unwrap().arguments
- {
- if let Some(syn::GenericArgument::Type(ty)) = args.args.first() {
- quote::quote!(#ty)
- } else {
- panic!("Expected to extract the success type of Result, but failed");
- }
- } else {
- panic!("Expected Result type to have generic parameters, but found none");
- }
- } else {
- panic!("Expected return type to be Result, but found different type");
- }
- }
- _ => panic!("Expected function to have return type, but found none"),
- };
-
- (arg_type, return_type)
-}