use std::collections::HashSet;
use actix_router::ResourceDef;
use proc_macro::TokenStream;
use proc_macro2::{Span, TokenStream as TokenStream2};
use quote::{quote, ToTokens, TokenStreamExt};
use syn::{punctuated::Punctuated, Ident, LitStr, Path, Token};
use crate::input_and_compile_error;
#[derive(Debug)]
pub struct RouteArgs {
pub(crate) path: syn::LitStr,
pub(crate) options: Punctuated<syn::MetaNameValue, Token![,]>,
}
impl syn::parse::Parse for RouteArgs {
fn parse(input: syn::parse::ParseStream<'_>) -> syn::Result<Self> {
let path = input.parse::<syn::LitStr>().map_err(|mut err| {
err.combine(syn::Error::new(
err.span(),
r#"invalid service definition, expected #[<method>("<path>")]"#,
));
err
})?;
let _ = ResourceDef::new(path.value());
if !input.peek(Token![,]) {
return Ok(Self {
path,
options: Punctuated::new(),
});
}
input.parse::<Token![,]>()?;
if input.cursor().literal().is_some() {
return Err(syn::Error::new(
Span::call_site(),
r#"Multiple paths specified! There should be only one."#,
));
}
let options = input.parse_terminated(syn::MetaNameValue::parse, Token![,])?;
Ok(Self { path, options })
}
}
macro_rules! standard_method_type {
(
$($variant:ident, $upper:ident, $lower:ident,)+
) => {
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum MethodType {
$(
$variant,
)+
}
impl MethodType {
fn as_str(&self) -> &'static str {
match self {
$(Self::$variant => stringify!($variant),)+
}
}
fn parse(method: &str) -> Result<Self, String> {
match method {
$(stringify!($upper) => Ok(Self::$variant),)+
_ => Err(format!("HTTP method must be uppercase: `{}`", method)),
}
}
pub(crate) fn from_path(method: &Path) -> Result<Self, ()> {
match () {
$(_ if method.is_ident(stringify!($lower)) => Ok(Self::$variant),)+
_ => Err(()),
}
}
}
};
}
standard_method_type! {
Get, GET, get,
Post, POST, post,
Put, PUT, put,
Delete, DELETE, delete,
Head, HEAD, head,
Connect, CONNECT, connect,
Options, OPTIONS, options,
Trace, TRACE, trace,
Patch, PATCH, patch,
}
impl TryFrom<&syn::LitStr> for MethodType {
type Error = syn::Error;
fn try_from(value: &syn::LitStr) -> Result<Self, Self::Error> {
Self::parse(value.value().as_str())
.map_err(|message| syn::Error::new_spanned(value, message))
}
}
impl ToTokens for MethodType {
fn to_tokens(&self, stream: &mut TokenStream2) {
let ident = Ident::new(self.as_str(), Span::call_site());
stream.append(ident);
}
}
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
enum MethodTypeExt {
Standard(MethodType),
Custom(LitStr),
}
impl MethodTypeExt {
fn to_tokens_single_guard(&self) -> TokenStream2 {
match self {
MethodTypeExt::Standard(method) => {
quote! {
.guard(::actix_web::guard::#method())
}
}
MethodTypeExt::Custom(lit) => {
quote! {
.guard(::actix_web::guard::Method(
::actix_web::http::Method::from_bytes(#lit.as_bytes()).unwrap()
))
}
}
}
}
fn to_tokens_multi_guard(&self, or_chain: Vec<impl ToTokens>) -> TokenStream2 {
debug_assert!(
!or_chain.is_empty(),
"empty or_chain passed to multi-guard constructor"
);
match self {
MethodTypeExt::Standard(method) => {
quote! {
.guard(
::actix_web::guard::Any(::actix_web::guard::#method())
#(#or_chain)*
)
}
}
MethodTypeExt::Custom(lit) => {
quote! {
.guard(
::actix_web::guard::Any(
::actix_web::guard::Method(
::actix_web::http::Method::from_bytes(#lit.as_bytes()).unwrap()
)
)
#(#or_chain)*
)
}
}
}
}
fn to_tokens_multi_guard_or_chain(&self) -> TokenStream2 {
match self {
MethodTypeExt::Standard(method_type) => {
quote! {
.or(::actix_web::guard::#method_type())
}
}
MethodTypeExt::Custom(lit) => {
quote! {
.or(
::actix_web::guard::Method(
::actix_web::http::Method::from_bytes(#lit.as_bytes()).unwrap()
)
)
}
}
}
}
}
impl ToTokens for MethodTypeExt {
fn to_tokens(&self, stream: &mut TokenStream2) {
match self {
MethodTypeExt::Custom(lit_str) => {
let ident = Ident::new(lit_str.value().as_str(), Span::call_site());
stream.append(ident);
}
MethodTypeExt::Standard(method) => method.to_tokens(stream),
}
}
}
impl TryFrom<&syn::LitStr> for MethodTypeExt {
type Error = syn::Error;
fn try_from(value: &syn::LitStr) -> Result<Self, Self::Error> {
match MethodType::try_from(value) {
Ok(method) => Ok(MethodTypeExt::Standard(method)),
Err(_) if value.value().chars().all(|c| c.is_ascii_uppercase()) => {
Ok(MethodTypeExt::Custom(value.clone()))
}
Err(err) => Err(err),
}
}
}
struct Args {
path: syn::LitStr,
resource_name: Option<syn::LitStr>,
guards: Vec<Path>,
wrappers: Vec<syn::Expr>,
methods: HashSet<MethodTypeExt>,
}
impl Args {
fn new(args: RouteArgs, method: Option<MethodType>) -> syn::Result<Self> {
let mut resource_name = None;
let mut guards = Vec::new();
let mut wrappers = Vec::new();
let mut methods = HashSet::new();
let is_route_macro = method.is_none();
if let Some(method) = method {
methods.insert(MethodTypeExt::Standard(method));
}
for nv in args.options {
if nv.path.is_ident("name") {
if let syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Str(lit),
..
}) = nv.value
{
resource_name = Some(lit);
} else {
return Err(syn::Error::new_spanned(
nv.value,
"Attribute name expects literal string",
));
}
} else if nv.path.is_ident("guard") {
if let syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Str(lit),
..
}) = nv.value
{
guards.push(lit.parse::<Path>()?);
} else {
return Err(syn::Error::new_spanned(
nv.value,
"Attribute guard expects literal string",
));
}
} else if nv.path.is_ident("wrap") {
if let syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Str(lit),
..
}) = nv.value
{
wrappers.push(lit.parse()?);
} else {
return Err(syn::Error::new_spanned(
nv.value,
"Attribute wrap expects type",
));
}
} else if nv.path.is_ident("method") {
if !is_route_macro {
return Err(syn::Error::new_spanned(
&nv,
"HTTP method forbidden here; to handle multiple methods, use `route` instead",
));
} else if let syn::Expr::Lit(syn::ExprLit {
lit: syn::Lit::Str(lit),
..
}) = nv.value.clone()
{
if !methods.insert(MethodTypeExt::try_from(&lit)?) {
return Err(syn::Error::new_spanned(
nv.value,
format!("HTTP method defined more than once: `{}`", lit.value()),
));
}
} else {
return Err(syn::Error::new_spanned(
nv.value,
"Attribute method expects literal string",
));
}
} else {
return Err(syn::Error::new_spanned(
nv.path,
"Unknown attribute key is specified; allowed: guard, method and wrap",
));
}
}
Ok(Args {
path: args.path,
resource_name,
guards,
wrappers,
methods,
})
}
}
pub struct Route {
name: syn::Ident,
args: Vec<Args>,
ast: syn::ItemFn,
doc_attributes: Vec<syn::Attribute>,
}
impl Route {
pub fn new(args: RouteArgs, ast: syn::ItemFn, method: Option<MethodType>) -> syn::Result<Self> {
let name = ast.sig.ident.clone();
let doc_attributes = ast
.attrs
.iter()
.filter(|attr| attr.path().is_ident("doc"))
.cloned()
.collect();
let args = Args::new(args, method)?;
if args.methods.is_empty() {
return Err(syn::Error::new(
Span::call_site(),
"The #[route(..)] macro requires at least one `method` attribute",
));
}
if matches!(ast.sig.output, syn::ReturnType::Default) {
return Err(syn::Error::new_spanned(
ast,
"Function has no return type. Cannot be used as handler",
));
}
Ok(Self {
name,
args: vec![args],
ast,
doc_attributes,
})
}
fn multiple(args: Vec<Args>, ast: syn::ItemFn) -> syn::Result<Self> {
let name = ast.sig.ident.clone();
let doc_attributes = ast
.attrs
.iter()
.filter(|attr| attr.path().is_ident("doc"))
.cloned()
.collect();
if matches!(ast.sig.output, syn::ReturnType::Default) {
return Err(syn::Error::new_spanned(
ast,
"Function has no return type. Cannot be used as handler",
));
}
Ok(Self {
name,
args,
ast,
doc_attributes,
})
}
}
impl ToTokens for Route {
fn to_tokens(&self, output: &mut TokenStream2) {
let Self {
name,
ast,
args,
doc_attributes,
} = self;
#[allow(unused_variables)] let vis = &ast.vis;
#[cfg(feature = "compat-routing-macros-force-pub")]
let vis = syn::Visibility::Public(<Token![pub]>::default());
let registrations: TokenStream2 = args
.iter()
.map(|args| {
let Args {
path,
resource_name,
guards,
wrappers,
methods,
} = args;
let resource_name = resource_name
.as_ref()
.map_or_else(|| name.to_string(), LitStr::value);
let method_guards = {
debug_assert!(!methods.is_empty(), "Args::methods should not be empty");
let mut others = methods.iter();
let first = others.next().unwrap();
if methods.len() > 1 {
let other_method_guards = others
.map(|method_ext| method_ext.to_tokens_multi_guard_or_chain())
.collect();
first.to_tokens_multi_guard(other_method_guards)
} else {
first.to_tokens_single_guard()
}
};
quote! {
let __resource = ::actix_web::Resource::new(#path)
.name(#resource_name)
#method_guards
#(.guard(::actix_web::guard::fn_guard(#guards)))*
#(.wrap(#wrappers))*
.to(#name);
::actix_web::dev::HttpServiceFactory::register(__resource, __config);
}
})
.collect();
let stream = quote! {
#(#doc_attributes)*
#[allow(non_camel_case_types, missing_docs)]
#vis struct #name;
impl ::actix_web::dev::HttpServiceFactory for #name {
fn register(self, __config: &mut actix_web::dev::AppService) {
#ast
#registrations
}
}
};
output.extend(stream);
}
}
pub(crate) fn with_method(
method: Option<MethodType>,
args: TokenStream,
input: TokenStream,
) -> TokenStream {
let args = match syn::parse(args) {
Ok(args) => args,
Err(err) => return input_and_compile_error(input, err),
};
let ast = match syn::parse::<syn::ItemFn>(input.clone()) {
Ok(ast) => ast,
Err(err) => return input_and_compile_error(input, err),
};
match Route::new(args, ast, method) {
Ok(route) => route.into_token_stream().into(),
Err(err) => input_and_compile_error(input, err),
}
}
pub(crate) fn with_methods(input: TokenStream) -> TokenStream {
let mut ast = match syn::parse::<syn::ItemFn>(input.clone()) {
Ok(ast) => ast,
Err(err) => return input_and_compile_error(input, err),
};
let (methods, others) = ast
.attrs
.into_iter()
.map(|attr| match MethodType::from_path(attr.path()) {
Ok(method) => Ok((method, attr)),
Err(_) => Err(attr),
})
.partition::<Vec<_>, _>(Result::is_ok);
ast.attrs = others.into_iter().map(Result::unwrap_err).collect();
let methods = match methods
.into_iter()
.map(Result::unwrap)
.map(|(method, attr)| {
attr.parse_args()
.and_then(|args| Args::new(args, Some(method)))
})
.collect::<Result<Vec<_>, _>>()
{
Ok(methods) if methods.is_empty() => {
return input_and_compile_error(
input,
syn::Error::new(
Span::call_site(),
"The #[routes] macro requires at least one `#[<method>(..)]` attribute.",
),
)
}
Ok(methods) => methods,
Err(err) => return input_and_compile_error(input, err),
};
match Route::multiple(methods, ast) {
Ok(route) => route.into_token_stream().into(),
Err(err) => input_and_compile_error(input, err),
}
}