async providers

v0.5/Cargo.toml

@@ -40,6 +40,7 @@ homepage = "https://fastn.com"
 # using the latest dependency, and what is the plan to move to the latest version.
 
 arcstr = "1"
+async-trait = "0.1"
 fastn-builtins = { path = "../fastn-builtins" }
 fastn-compiler = { path = "fastn-compiler" }
 fastn-continuation = { path = "fastn-continuation" }

v0.5/fastn-continuation/Cargo.toml

@@ -8,4 +8,8 @@ license.workspace = true
 repository.workspace = true
 homepage.workspace = true
 
+[features]
+async_provider = ["async-trait"]
+
 [dependencies]
+async-trait = { workspace = true, optional = true }

v0.5/fastn-continuation/src/lib.rs

@@ -10,6 +10,25 @@ pub trait Provider {
     fn provide(&self, input: Self::Input) -> Self::Output;
 }
 
+#[cfg(feature = "async_provider")]
+#[async_trait::async_trait]
+pub trait AsyncProvider {
+    type Input;
+    type Output;
+
+    async fn provide(&self, input: Self::Input) -> Self::Output;
+}
+
+#[cfg(feature = "async_provider")]
+#[async_trait::async_trait]
+pub trait AsyncProviderWith {
+    type Input;
+    type Output;
+    type Context;
+
+    async fn provide(&self, context: &mut Self::Context, input: Self::Input) -> Self::Output;
+}
+
 pub trait ProviderWith {
     type Input;
     type Output;
@@ -18,22 +37,6 @@ pub trait ProviderWith {
     fn provide(&self, context: &mut Self::Context, input: Self::Input) -> Self::Output;
 }
 
-// impl<I, O> Provider for dyn Fn(I) -> O {
-//     type Input = I;
-//     type Output = O;
-//     fn provide(&self, input: Self::Input) -> Self::Output {
-//         self(input)
-//     }
-// }
-
-// impl<I, O> Provider for fn(I) -> O {
-//     type Input = I;
-//     type Output = O;
-//     fn provide(&self, input: Self::Input) -> Self::Output {
-//         self(input)
-//     }
-// }
-
 pub trait Continuation {
     type Output;
     type NeededInput;
@@ -108,7 +111,24 @@ impl<C: Continuation> Result<C> {
         }
     }
 
-    pub async fn consume_async<Fut>(mut self, f: impl Fn(C::NeededInput) -> Fut) -> C::Output
+    #[cfg(feature = "async_provider")]
+    pub async fn consume_async<P>(mut self, p: P) -> C::Output
+    where
+        P: AsyncProvider<Input = C::NeededInput, Output = C::NeededOutput>,
+    {
+        loop {
+            match self {
+                Result::Stuck(ic, input) => {
+                    self = ic.continue_after(p.provide(input).await);
+                }
+                Result::Done(c) => {
+                    return c;
+                }
+            }
+        }
+    }
+
+    pub async fn consume_async_fn<Fut>(mut self, f: impl Fn(C::NeededInput) -> Fut) -> C::Output
     where
         Fut: std::future::Future<Output = C::NeededOutput>,
     {
@@ -124,7 +144,25 @@ impl<C: Continuation> Result<C> {
         }
     }
 
-    pub async fn consume_with_async<Fut>(
+    #[cfg(feature = "async_provider")]
+    pub async fn consume_with_async<P>(mut self, p: P) -> C::Output
+    where
+        P: AsyncProviderWith<Input = C::NeededInput, Output = C::NeededOutput, Context = C>,
+    {
+        loop {
+            match self {
+                Result::Stuck(mut ic, input) => {
+                    let o = p.provide(&mut ic, input).await;
+                    self = ic.continue_after(o);
+                }
+                Result::Done(c) => {
+                    return c;
+                }
+            }
+        }
+    }
+
+    pub async fn consume_with_async_fn<Fut>(
         mut self,
         f: impl Fn(&mut C, C::NeededInput) -> Fut,
     ) -> C::Output

v0.5/fastn/src/main.rs

@@ -3,7 +3,7 @@ async fn main() {
     let command = fastn::commands::parse();
     let mut package = fastn_package::Package::reader().consume_fn(fastn::full_filler);
     let router = fastn_router::Router::reader()
-        .consume_async(fastn::full_filler_async)
+        .consume_async_fn(fastn::full_filler_async)
         .await;
     // read config here and pass to everyone?
     // do common build stuff here