feat: export candid

examples/print/src/print_rs/Cargo.toml

@@ -13,5 +13,9 @@ crate-type = ["cdylib"]
 [dependencies]
 ic-cdk = { path = "../../../../src/ic-cdk", version = "0.1.0" }
 ic-cdk-macros = { path = "../../../../src/ic-cdk-macros", version = "0.1.0" }
-candid = "0.6.2"
+candid = { git = "https://github.com/dfinity/candid.git", branch = "derive-func" }
 serde = "1.0.111"
+
+[features]
+default = []
+export_candid = ["ic-cdk/wasi"]

examples/print/src/print_rs/lib.rs

@@ -1,4 +1,26 @@
+use candid::{CandidType, Deserialize};
+
 #[ic_cdk_macros::query]
 fn print() {
     ic_cdk::print("Hello World");
 }
+
+#[ic_cdk_macros::update(name = "🐂")]
+fn test(name: String) -> (usize, String) {
+    (name.len(), name)
+}
+
+#[derive(CandidType, Deserialize)]
+struct List { head: i8, tail: Option<Box<List>> }
+
+#[derive(CandidType, Deserialize)]
+enum A { A1(u16), A2(List), A3(String, candid::Principal) }
+
+#[ic_cdk_macros::query]
+fn id_struct(a:List) -> List { a }
+
+#[ic_cdk_macros::update]
+fn id_variant(a:A) -> A { a }
+
+ic_cdk_macros::export_candid!();
+

src/ic-cdk-macros/Cargo.toml

@@ -16,7 +16,7 @@ include = ["src", "Cargo.toml", "LICENSE", "README.md"]
 proc-macro = true
 
 [dependencies]
-candid = "0.6.2"
+candid = { git = "https://github.com/dfinity/candid.git", branch = "derive-func" }
 ic-cdk = { path = "../ic-cdk", version = "0.1" }
 syn = { version = "1.0", features = ["fold", "full"] }
 quote = "1.0"

src/ic-cdk-macros/src/export.rs

@@ -24,10 +24,10 @@ enum MethodType {
 
 impl MethodType {
     pub fn is_lifecycle(&self) -> bool {
-        match self {
-            MethodType::Init | MethodType::PreUpgrade | MethodType::PostUpgrade => true,
-            _ => false,
-        }
+        matches!(
+            self,
+            MethodType::Init | MethodType::PreUpgrade | MethodType::PostUpgrade
+        )
     }
 }
 
@@ -131,15 +131,16 @@ fn dfn_macro(
         &format!("{}_{}_", name.to_string(), crate::id()),
         Span::call_site(),
     );
-
+    let rename = attrs.name.unwrap_or_else(|| name.to_string());
     let export_name = if method.is_lifecycle() {
         format!("{}", method)
     } else {
-        format!(
-            "{0} {1}",
-            method,
-            attrs.name.unwrap_or_else(|| name.to_string())
-        )
+        format!("{0} {1}", method, rename,)
+    };
+    let candid_method_attr = match method {
+        MethodType::Query => quote! { #[candid::candid_method(query, rename = #rename)] },
+        MethodType::Update => quote! { #[candid::candid_method(update, rename = #rename)] },
+        _ => quote! {},
     };
 
     let function_call = if is_async {
@@ -183,7 +184,7 @@ fn dfn_macro(
         quote! {}
     };
 
-    Ok(quote! {
+    let res = quote! {
         #[export_name = #export_name]
         fn #outer_function_ident() {
             ic_cdk::setup();
@@ -197,8 +198,10 @@ fn dfn_macro(
             });
         }
 
+        #candid_method_attr
         #item
-    })
+    };
+    Ok(res)
 }
 
 pub(crate) fn ic_query(

src/ic-cdk-macros/src/lib.rs

@@ -68,3 +68,23 @@ pub fn post_upgrade(attr: TokenStream, item: TokenStream) -> TokenStream {
 pub fn import(attr: TokenStream, item: TokenStream) -> TokenStream {
     handle_debug_and_errors(import::ic_import, "ic_import", attr, item)
 }
+
+#[proc_macro]
+pub fn export_candid(_input: TokenStream) -> TokenStream {
+    let res = quote::quote! {
+        candid::export_service!();
+
+        #[ic_cdk_macros::query(name = "__get_candid_interface_tmp_hack")]
+        fn export_candid() -> String {
+            __export_service()
+        }
+        #[cfg(feature = "export_candid")]
+        #[no_mangle]
+        pub unsafe extern "C" fn _start() {
+            let result = export_candid();
+            let ret = unsafe { ::ic_cdk::api::wasi::print(&result) };
+            ic_cdk::api::wasi::proc_exit(ret as u32);
+        }
+    };
+    res.into()
+}

src/ic-cdk/Cargo.toml

@@ -13,11 +13,12 @@ keywords = ["internet-computer", "types", "dfinity", "canister", "cdk"]
 include = ["src", "Cargo.toml", "LICENSE", "README.md"]
 
 [dependencies]
-candid = "0.6.2"
+candid = { git = "https://github.com/dfinity/candid.git", branch = "derive-func" }
 cfg-if = "0.1.10"
 ic-types = "0.1.1"
 serde = "1.0.110"
 wee_alloc = { version = "0.4.5" }
 
 [features]
 experimental = []
+wasi = []

src/ic-cdk/src/api.rs

@@ -2,6 +2,9 @@
 use ic_types::Principal;
 use std::convert::TryFrom;
 
+#[cfg(all(target_arch = "wasm32", feature = "wasi"))]
+pub mod wasi;
+
 pub mod call;
 pub mod stable;
 

src/ic-cdk/src/api/ic0.rs

@@ -39,14 +39,14 @@ macro_rules! _ic0_module_ret {
 macro_rules! ic0_module {
     ( $( ic0. $name: ident : ( $( $argname: ident : $argtype: ty ),* ) -> $rettype: tt ; )+ ) => {
 
-        #[cfg(target_arch = "wasm32")]
+        #[cfg(all(target_arch = "wasm32", not(feature = "wasi")))]
         #[link(wasm_import_module = "ic0")]
         extern "C" {
             $(pub(super) fn $name($( $argname: $argtype, )*) -> _ic0_module_ret!($rettype) ;)*
         }
 
         $(
-        #[cfg(not(target_arch = "wasm32"))]
+        #[cfg(not(all(target_arch = "wasm32", not(feature = "wasi"))))]
         pub(super) unsafe fn $name($( $argname: $argtype, )*) -> _ic0_module_ret!($rettype) {
             let _ = ( $( $argname, )* );  // make sure the arguments are used.
             panic!("{} should only be called inside canisters.", stringify!( $name ));

src/ic-cdk/src/api/wasi.rs

@@ -0,0 +1,25 @@
+type Fd = u32;
+type Size = usize;
+pub type Errno = i32;
+pub type Rval = u32;
+
+#[repr(C)]
+pub struct Ciovec {
+    buf: *const u8,
+    buf_len: Size,
+}
+
+#[link(wasm_import_module = "wasi_snapshot_preview1")]
+extern "C" {
+    pub fn fd_write(fd: Fd, iovs_ptr: *const Ciovec, iovs_len: Size, nwritten: *mut Size) -> Errno;
+    pub fn proc_exit(rval: Rval);
+}
+pub unsafe fn print(text: &str) -> Errno {
+    let ciovec = Ciovec {
+        buf: text.as_ptr(),
+        buf_len: text.len(),
+    };
+    let ciovecs = [ciovec];
+    let mut nwritten = 0;
+    fd_write(1, ciovecs.as_ptr(), ciovecs.len(), &mut nwritten)
+}

src/ic-cdk/src/lib.rs

@@ -33,7 +33,7 @@ pub fn block_on<F: 'static + std::future::Future<Output = ()>>(future: F) {
 }
 
 /// Format and then print the formatted message
-#[cfg(target_arch = "wasm32")]
+#[cfg(all(target_arch = "wasm32", not(feature = "wasi")))]
 #[macro_export]
 macro_rules! println {
     ($fmt:expr) => (ic_cdk::print(format!($fmt)));