Scope macro (#3136)

* add scope proc macro

* Update scope macro code to work with current HttpServiceFactory

* started some test code

* add some unit tests

* code formatting cleanup

* add another test for combining and calling 2 scopes

* format code with formatter

* Update actix-web-codegen/src/lib.rs with comment documentation fix

Co-authored-by: oliver <151407407+kwfn@users.noreply.github.com>

* work in progress. revised procedural macro to change othe macro call

* add tests again. refactor nested code.

* clean up code. fix bugs with route and method attributes with parameters

* clean up for rust fmt

* clean up for rust fmt

* fix out of date comment for scope macro

* sync to master branch by adding test_wrap

* needed to format code

* test: split out scope tests

* test: add negative tests

* chore: move imports back inside (?)

* docs: tweak scope docs

* fix: prevent trailing slashes in scope prefixes

* chore: address clippy lints

---------

Co-authored-by: oliver <151407407+kwfn@users.noreply.github.com>
Co-authored-by: Rob Ede <robjtede@icloud.com>

actix-web-codegen/CHANGES.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- Add `#[scope]` macro.
 - Prevent inclusion of default `actix-router` features.
 - Minimum supported Rust version (MSRV) is now 1.72.
 

actix-web-codegen/src/lib.rs

@@ -83,6 +83,7 @@ use proc_macro::TokenStream;
 use quote::quote;
 
 mod route;
+mod scope;
 
 /// Creates resource handler, allowing multiple HTTP method guards.
 ///
@@ -197,6 +198,43 @@ method_macro!(Options, options);
 method_macro!(Trace, trace);
 method_macro!(Patch, patch);
 
+/// Prepends a path prefix to all handlers using routing macros inside the attached module.
+///
+/// # Syntax
+///
+/// ```
+/// # use actix_web_codegen::scope;
+/// #[scope("/prefix")]
+/// mod api {
+///     // ...
+/// }
+/// ```
+///
+/// # Arguments
+///
+/// - `"/prefix"` - Raw literal string to be prefixed onto contained handlers' paths.
+///
+/// # Example
+///
+/// ```
+/// # use actix_web_codegen::{scope, get};
+/// # use actix_web::Responder;
+/// #[scope("/api")]
+/// mod api {
+///     # use super::*;
+///     #[get("/hello")]
+///     pub async fn hello() -> impl Responder {
+///         // this has path /api/hello
+///         "Hello, world!"
+///     }
+/// }
+/// # fn main() {}
+/// ```
+#[proc_macro_attribute]
+pub fn scope(args: TokenStream, input: TokenStream) -> TokenStream {
+    scope::with_scope(args, input)
+}
+
 /// Marks async main function as the Actix Web system entry-point.
 ///
 /// Note that Actix Web also works under `#[tokio::main]` since version 4.0. However, this macro is
@@ -240,3 +278,15 @@ pub fn test(_: TokenStream, item: TokenStream) -> TokenStream {
     output.extend(item);
     output
 }
+
+/// Converts the error to a token stream and appends it to the original input.
+///
+/// Returning the original input in addition to the error is good for IDEs which can gracefully
+/// recover and show more precise errors within the macro body.
+///
+/// See <https://github.com/rust-analyzer/rust-analyzer/issues/10468> for more info.
+fn input_and_compile_error(mut item: TokenStream, err: syn::Error) -> TokenStream {
+    let compile_err = TokenStream::from(err.to_compile_error());
+    item.extend(compile_err);
+    item
+}

actix-web-codegen/src/route.rs

@@ -6,10 +6,12 @@ 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 {
-    path: syn::LitStr,
-    options: Punctuated<syn::MetaNameValue, Token![,]>,
+    pub(crate) path: syn::LitStr,
+    pub(crate) options: Punctuated<syn::MetaNameValue, Token![,]>,
 }
 
 impl syn::parse::Parse for RouteArgs {
@@ -78,7 +80,7 @@ macro_rules! standard_method_type {
                 }
             }
 
-            fn from_path(method: &Path) -> Result<Self, ()> {
+            pub(crate) fn from_path(method: &Path) -> Result<Self, ()> {
                 match () {
                     $(_ if method.is_ident(stringify!($lower)) => Ok(Self::$variant),)+
                     _ => Err(()),
@@ -542,15 +544,3 @@ pub(crate) fn with_methods(input: TokenStream) -> TokenStream {
         Err(err) => input_and_compile_error(input, err),
     }
 }
-
-/// Converts the error to a token stream and appends it to the original input.
-///
-/// Returning the original input in addition to the error is good for IDEs which can gracefully
-/// recover and show more precise errors within the macro body.
-///
-/// See <https://github.com/rust-analyzer/rust-analyzer/issues/10468> for more info.
-fn input_and_compile_error(mut item: TokenStream, err: syn::Error) -> TokenStream {
-    let compile_err = TokenStream::from(err.to_compile_error());
-    item.extend(compile_err);
-    item
-}

actix-web-codegen/src/scope.rs

@@ -0,0 +1,103 @@
+use proc_macro::TokenStream;
+use proc_macro2::{Span, TokenStream as TokenStream2};
+use quote::{quote, ToTokens as _};
+
+use crate::{
+    input_and_compile_error,
+    route::{MethodType, RouteArgs},
+};
+
+pub fn with_scope(args: TokenStream, input: TokenStream) -> TokenStream {
+    match with_scope_inner(args, input.clone()) {
+        Ok(stream) => stream,
+        Err(err) => input_and_compile_error(input, err),
+    }
+}
+
+fn with_scope_inner(args: TokenStream, input: TokenStream) -> syn::Result<TokenStream> {
+    if args.is_empty() {
+        return Err(syn::Error::new(
+            Span::call_site(),
+            "missing arguments for scope macro, expected: #[scope(\"/prefix\")]",
+        ));
+    }
+
+    let scope_prefix = syn::parse::<syn::LitStr>(args.clone()).map_err(|err| {
+        syn::Error::new(
+            err.span(),
+            "argument to scope macro is not a string literal, expected: #[scope(\"/prefix\")]",
+        )
+    })?;
+
+    let scope_prefix_value = scope_prefix.value();
+
+    if scope_prefix_value.ends_with('/') {
+        // trailing slashes cause non-obvious problems
+        // it's better to point them out to developers rather than
+
+        return Err(syn::Error::new(
+            scope_prefix.span(),
+            "scopes should not have trailing slashes; see https://docs.rs/actix-web/4/actix_web/struct.Scope.html#avoid-trailing-slashes",
+        ));
+    }
+
+    let mut module = syn::parse::<syn::ItemMod>(input).map_err(|err| {
+        syn::Error::new(err.span(), "#[scope] macro must be attached to a module")
+    })?;
+
+    // modify any routing macros (method or route[s]) attached to
+    // functions by prefixing them with this scope macro's argument
+    if let Some((_, items)) = &mut module.content {
+        for item in items {
+            if let syn::Item::Fn(fun) = item {
+                fun.attrs = fun
+                    .attrs
+                    .iter()
+                    .map(|attr| modify_attribute_with_scope(attr, &scope_prefix_value))
+                    .collect();
+            }
+        }
+    }
+
+    Ok(module.to_token_stream().into())
+}
+
+/// Checks if the attribute is a method type and has a route path, then modifies it.
+fn modify_attribute_with_scope(attr: &syn::Attribute, scope_path: &str) -> syn::Attribute {
+    match (attr.parse_args::<RouteArgs>(), attr.clone().meta) {
+        (Ok(route_args), syn::Meta::List(meta_list)) if has_allowed_methods_in_scope(attr) => {
+            let modified_path = format!("{}{}", scope_path, route_args.path.value());
+
+            let options_tokens: Vec<TokenStream2> = route_args
+                .options
+                .iter()
+                .map(|option| {
+                    quote! { ,#option }
+                })
+                .collect();
+
+            let combined_options_tokens: TokenStream2 =
+                options_tokens
+                    .into_iter()
+                    .fold(TokenStream2::new(), |mut acc, ts| {
+                        acc.extend(std::iter::once(ts));
+                        acc
+                    });
+
+            syn::Attribute {
+                meta: syn::Meta::List(syn::MetaList {
+                    tokens: quote! { #modified_path #combined_options_tokens },
+                    ..meta_list.clone()
+                }),
+                ..attr.clone()
+            }
+        }
+        _ => attr.clone(),
+    }
+}
+
+fn has_allowed_methods_in_scope(attr: &syn::Attribute) -> bool {
+    MethodType::from_path(attr.path()).is_ok()
+        || attr.path().is_ident("route")
+        || attr.path().is_ident("ROUTE")
+}

actix-web-codegen/tests/scopes.rs

@@ -0,0 +1,200 @@
+use actix_web::{guard::GuardContext, http, http::header, web, App, HttpResponse, Responder};
+use actix_web_codegen::{delete, get, post, route, routes, scope};
+
+pub fn image_guard(ctx: &GuardContext) -> bool {
+    ctx.header::<header::Accept>()
+        .map(|h| h.preference() == "image/*")
+        .unwrap_or(false)
+}
+
+#[scope("/test")]
+mod scope_module {
+    // ensure that imports can be brought into the scope
+    use super::*;
+
+    #[get("/test/guard", guard = "image_guard")]
+    pub async fn guard() -> impl Responder {
+        HttpResponse::Ok()
+    }
+
+    #[get("/test")]
+    pub async fn test() -> impl Responder {
+        HttpResponse::Ok().finish()
+    }
+
+    #[get("/twice-test/{value}")]
+    pub async fn twice(value: web::Path<String>) -> impl actix_web::Responder {
+        let int_value: i32 = value.parse().unwrap_or(0);
+        let doubled = int_value * 2;
+        HttpResponse::Ok().body(format!("Twice value: {}", doubled))
+    }
+
+    #[post("/test")]
+    pub async fn post() -> impl Responder {
+        HttpResponse::Ok().body("post works")
+    }
+
+    #[delete("/test")]
+    pub async fn delete() -> impl Responder {
+        "delete works"
+    }
+
+    #[route("/test", method = "PUT", method = "PATCH", method = "CUSTOM")]
+    pub async fn multiple_shared_path() -> impl Responder {
+        HttpResponse::Ok().finish()
+    }
+
+    #[routes]
+    #[head("/test1")]
+    #[connect("/test2")]
+    #[options("/test3")]
+    #[trace("/test4")]
+    async fn multiple_separate_paths() -> impl Responder {
+        HttpResponse::Ok().finish()
+    }
+
+    // test calling this from other mod scope with scope attribute...
+    pub fn mod_common(message: String) -> impl actix_web::Responder {
+        HttpResponse::Ok().body(message)
+    }
+}
+
+/// Scope doc string to check in cargo expand.
+#[scope("/v1")]
+mod mod_scope_v1 {
+    use super::*;
+
+    /// Route doc string to check in cargo expand.
+    #[get("/test")]
+    pub async fn test() -> impl Responder {
+        scope_module::mod_common("version1 works".to_string())
+    }
+}
+
+#[scope("/v2")]
+mod mod_scope_v2 {
+    use super::*;
+
+    // check to make sure non-function tokens in the scope block are preserved...
+    enum TestEnum {
+        Works,
+    }
+
+    #[get("/test")]
+    pub async fn test() -> impl Responder {
+        // make sure this type still exists...
+        let test_enum = TestEnum::Works;
+
+        match test_enum {
+            TestEnum::Works => scope_module::mod_common("version2 works".to_string()),
+        }
+    }
+}
+
+#[actix_rt::test]
+async fn scope_get_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::test));
+
+    let request = srv.request(http::Method::GET, srv.url("/test/test"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+}
+
+#[actix_rt::test]
+async fn scope_get_param_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::twice));
+
+    let request = srv.request(http::Method::GET, srv.url("/test/twice-test/4"));
+    let mut response = request.send().await.unwrap();
+    let body = response.body().await.unwrap();
+    let body_str = String::from_utf8(body.to_vec()).unwrap();
+    assert_eq!(body_str, "Twice value: 8");
+}
+
+#[actix_rt::test]
+async fn scope_post_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::post));
+
+    let request = srv.request(http::Method::POST, srv.url("/test/test"));
+    let mut response = request.send().await.unwrap();
+    let body = response.body().await.unwrap();
+    let body_str = String::from_utf8(body.to_vec()).unwrap();
+    assert_eq!(body_str, "post works");
+}
+
+#[actix_rt::test]
+async fn multiple_shared_path_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::multiple_shared_path));
+
+    let request = srv.request(http::Method::PUT, srv.url("/test/test"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+
+    let request = srv.request(http::Method::PATCH, srv.url("/test/test"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+}
+
+#[actix_rt::test]
+async fn multiple_multi_path_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::multiple_separate_paths));
+
+    let request = srv.request(http::Method::HEAD, srv.url("/test/test1"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+
+    let request = srv.request(http::Method::CONNECT, srv.url("/test/test2"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+
+    let request = srv.request(http::Method::OPTIONS, srv.url("/test/test3"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+
+    let request = srv.request(http::Method::TRACE, srv.url("/test/test4"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+}
+
+#[actix_rt::test]
+async fn scope_delete_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::delete));
+
+    let request = srv.request(http::Method::DELETE, srv.url("/test/test"));
+    let mut response = request.send().await.unwrap();
+    let body = response.body().await.unwrap();
+    let body_str = String::from_utf8(body.to_vec()).unwrap();
+    assert_eq!(body_str, "delete works");
+}
+
+#[actix_rt::test]
+async fn scope_get_with_guard_async() {
+    let srv = actix_test::start(|| App::new().service(scope_module::guard));
+
+    let request = srv
+        .request(http::Method::GET, srv.url("/test/test/guard"))
+        .insert_header(("Accept", "image/*"));
+    let response = request.send().await.unwrap();
+    assert!(response.status().is_success());
+}
+
+#[actix_rt::test]
+async fn scope_v1_v2_async() {
+    let srv = actix_test::start(|| {
+        App::new()
+            .service(mod_scope_v1::test)
+            .service(mod_scope_v2::test)
+    });
+
+    let request = srv.request(http::Method::GET, srv.url("/v1/test"));
+    let mut response = request.send().await.unwrap();
+    let body = response.body().await.unwrap();
+    let body_str = String::from_utf8(body.to_vec()).unwrap();
+    assert_eq!(body_str, "version1 works");
+
+    let request = srv.request(http::Method::GET, srv.url("/v2/test"));
+    let mut response = request.send().await.unwrap();
+    let body = response.body().await.unwrap();
+    let body_str = String::from_utf8(body.to_vec()).unwrap();
+    assert_eq!(body_str, "version2 works");
+}

actix-web-codegen/tests/trybuild.rs

@@ -18,6 +18,11 @@ fn compile_macros() {
     t.compile_fail("tests/trybuild/routes-missing-method-fail.rs");
     t.compile_fail("tests/trybuild/routes-missing-args-fail.rs");
 
+    t.compile_fail("tests/trybuild/scope-on-handler.rs");
+    t.compile_fail("tests/trybuild/scope-missing-args.rs");
+    t.compile_fail("tests/trybuild/scope-invalid-args.rs");
+    t.compile_fail("tests/trybuild/scope-trailing-slash.rs");
+
     t.pass("tests/trybuild/docstring-ok.rs");
 
     t.pass("tests/trybuild/test-runtime.rs");

actix-web-codegen/tests/trybuild/scope-invalid-args.rs

@@ -0,0 +1,14 @@
+use actix_web_codegen::scope;
+
+const PATH: &str = "/api";
+
+#[scope(PATH)]
+mod api_const {}
+
+#[scope(true)]
+mod api_bool {}
+
+#[scope(123)]
+mod api_num {}
+
+fn main() {}

actix-web-codegen/tests/trybuild/scope-invalid-args.stderr

@@ -0,0 +1,17 @@
+error: argument to scope macro is not a string literal, expected: #[scope("/prefix")]
+ --> tests/trybuild/scope-invalid-args.rs:5:9
+  |
+5 | #[scope(PATH)]
+  |         ^^^^
+
+error: argument to scope macro is not a string literal, expected: #[scope("/prefix")]
+ --> tests/trybuild/scope-invalid-args.rs:8:9
+  |
+8 | #[scope(true)]
+  |         ^^^^
+
+error: argument to scope macro is not a string literal, expected: #[scope("/prefix")]
+  --> tests/trybuild/scope-invalid-args.rs:11:9
+   |
+11 | #[scope(123)]
+   |         ^^^

actix-web-codegen/tests/trybuild/scope-missing-args.rs

@@ -0,0 +1,6 @@
+use actix_web_codegen::scope;
+
+#[scope]
+mod api {}
+
+fn main() {}

actix-web-codegen/tests/trybuild/scope-missing-args.stderr

@@ -0,0 +1,7 @@
+error: missing arguments for scope macro, expected: #[scope("/prefix")]
+ --> tests/trybuild/scope-missing-args.rs:3:1
+  |
+3 | #[scope]
+  | ^^^^^^^^
+  |
+  = note: this error originates in the attribute macro `scope` (in Nightly builds, run with -Z macro-backtrace for more info)

actix-web-codegen/tests/trybuild/scope-on-handler.rs

@@ -0,0 +1,8 @@
+use actix_web_codegen::scope;
+
+#[scope("/api")]
+async fn index() -> &'static str {
+    "Hello World!"
+}
+
+fn main() {}

actix-web-codegen/tests/trybuild/scope-on-handler.stderr

@@ -0,0 +1,5 @@
+error: #[scope] macro must be attached to a module
+ --> tests/trybuild/scope-on-handler.rs:4:1
+  |
+4 | async fn index() -> &'static str {
+  | ^^^^^

actix-web-codegen/tests/trybuild/scope-trailing-slash.rs

@@ -0,0 +1,6 @@
+use actix_web_codegen::scope;
+
+#[scope("/api/")]
+mod api {}
+
+fn main() {}

actix-web-codegen/tests/trybuild/scope-trailing-slash.stderr

@@ -0,0 +1,5 @@
+error: scopes should not have trailing slashes; see https://docs.rs/actix-web/4/actix_web/struct.Scope.html#avoid-trailing-slashes
+ --> tests/trybuild/scope-trailing-slash.rs:3:9
+  |
+3 | #[scope("/api/")]
+  |         ^^^^^^^

actix-web/src/lib.rs

@@ -145,5 +145,6 @@ codegen_reexport!(delete);
 codegen_reexport!(trace);
 codegen_reexport!(connect);
 codegen_reexport!(options);
+codegen_reexport!(scope);
 
 pub(crate) type BoxError = Box<dyn std::error::Error>;

awc/src/client/connector.rs

@@ -1080,7 +1080,7 @@ mod resolver {
 
         // resolver struct is cached in thread local so new clients can reuse the existing instance
         thread_local! {
-            static TRUST_DNS_RESOLVER: RefCell<Option<Resolver>> = RefCell::new(None);
+            static TRUST_DNS_RESOLVER: RefCell<Option<Resolver>> = const { RefCell::new(None) };
         }
 
         // get from thread local or construct a new trust-dns resolver.

justfile

@@ -4,7 +4,7 @@ _list:
 # Format workspace.
 fmt:
     cargo +nightly fmt
-    npx -y prettier --write $(fd --type=file --hidden --extension=md --extension=yml)
+    fd --hidden --type=file --extension=md --extension=yml --exec-batch npx -y prettier --write
 
 # Downgrade dev-dependencies necessary to run MSRV checks/tests.
 [private]
@@ -32,6 +32,10 @@ all_crate_features := if os() == "linux" {
     "--features='" + non_linux_all_features_list + "'"
 }
 
+# Run Clippy over workspace.
+clippy toolchain="":
+    cargo {{ toolchain }} clippy --workspace --all-targets {{ all_crate_features }}
+
 # Test workspace using MSRV.
 test-msrv: downgrade-for-msrv (test msrv_rustup)