implement auto-documenting routes

core/codegen/src/attribute/route/mod.rs

@@ -319,6 +319,9 @@ fn codegen_route(route: Route) -> Result<TokenStream> {
     let rank = Optional(route.attr.rank);
     let format = Optional(route.attr.format.as_ref());
 
+    // Get the doc comment
+    let docstring = &route.docstring;
+
     Ok(quote! {
         #handler_fn
 
@@ -353,6 +356,7 @@ fn codegen_route(route: Route) -> Result<TokenStream> {
                     format: #format,
                     rank: #rank,
                     sentinels: #sentinels,
+                    docstring: #docstring.to_string(),
                 }
             }
 

core/codegen/src/attribute/route/parse.rs

@@ -29,6 +29,8 @@ pub struct Route {
     pub handler: syn::ItemFn,
     /// The parsed arguments to the user's function.
     pub arguments: Arguments,
+    /// The doc comment describing this route
+    pub docstring: String
 }
 
 type ArgumentMap = IndexMap<Name, (syn::Ident, syn::Type)>;
@@ -209,9 +211,11 @@ impl Route {
             })
             .collect();
 
+        let docstring = String::from_attrs("doc", &handler.attrs)?.join("\n");
+
         diags.head_err_or(Route {
             attr, path_params, query_params, data_guard, request_guards,
-            handler, arguments,
+            handler, arguments, docstring
         })
     }
 }

core/lib/src/doc/has_schema.rs

@@ -0,0 +1,29 @@
+mod array_impls;
+mod box_impls;
+mod number_impls;
+mod string_impls;
+
+
+pub enum SchemaKind {
+    Null,
+    Map,
+    List,
+    String,
+    Num,
+    Int,
+    Bool,
+}
+
+pub struct Schema<T> {
+    pub min_value: Option<T>,
+    pub max_value: Option<T>,
+    pub description: Option<String>,
+    pub example: Option<T>,
+    pub name: String,
+    pub kind: SchemaKind,
+
+}
+
+pub trait HasSchema: Sized {
+    fn schema() -> Schema<Self>;
+}

core/lib/src/doc/has_schema/array_impls.rs

@@ -0,0 +1,15 @@
+
+
+impl<T: super::HasSchema, const N: usize> super::HasSchema for [T; N] {
+    fn schema() -> super::Schema<Self> {
+        let base_schema = T::schema();
+        super::Schema {
+            min_value: None,
+            max_value: None,
+            description: None,
+            example: None, // making an array example requires that T be Copy...
+            name: format!("Array of {} {}'s", N, base_schema.name),
+            kind: super::SchemaKind::List,
+        }
+    }
+}

core/lib/src/doc/has_schema/box_impls.rs

@@ -0,0 +1,15 @@
+
+
+impl<T: super::HasSchema> super::HasSchema for Box<T> {
+    fn schema() -> super::Schema<Self> {
+        let base_schema = T::schema();
+        super::Schema {
+            min_value: base_schema.min_value.map(Box::new),
+            max_value: base_schema.max_value.map(Box::new),
+            description: base_schema.description,
+            example: base_schema.example.map(Box::new),
+            name: base_schema.name,
+            kind: base_schema.kind,
+        }
+    }
+}

core/lib/src/doc/has_schema/number_impls.rs

@@ -0,0 +1,129 @@
+impl super::HasSchema for i8 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(i8::MIN),
+            max_value: Some(i8::MAX),
+            description: None,
+            example: Some(1),
+            name: "signed 8-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for i16 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(i16::MIN),
+            max_value: Some(i16::MAX),
+            description: None,
+            example: Some(1),
+            name: "signed 16-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for i32 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(i32::MIN),
+            max_value: Some(i32::MAX),
+            description: None,
+            example: Some(1),
+            name: "signed 32-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for i64 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(i64::MIN),
+            max_value: Some(i64::MAX),
+            description: None,
+            example: Some(1),
+            name: "signed 64-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for i128 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(i128::MIN),
+            max_value: Some(i128::MAX),
+            description: None,
+            example: Some(1),
+            name: "signed 128-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for u8 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(u8::MIN),
+            max_value: Some(u8::MAX),
+            description: None,
+            example: Some(1),
+            name: "unsigned 8-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for u16 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(u16::MIN),
+            max_value: Some(u16::MAX),
+            description: None,
+            example: Some(1),
+            name: "unsigned 16-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for u32 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(u32::MIN),
+            max_value: Some(u32::MAX),
+            description: None,
+            example: Some(1),
+            name: "unsigned 32-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for u64 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(u64::MIN),
+            max_value: Some(u64::MAX),
+            description: None,
+            example: Some(1),
+            name: "unsigned 64-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}
+
+impl super::HasSchema for u128 {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: Some(u128::MIN),
+            max_value: Some(u128::MAX),
+            description: None,
+            example: Some(1),
+            name: "unsigned 128-bits integer".to_string(),
+            kind: super::SchemaKind::Int,
+        }
+    }
+}

core/lib/src/doc/has_schema/string_impls.rs

@@ -0,0 +1,27 @@
+
+
+impl<'a> super::HasSchema for &'a str {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: None,
+            max_value: None,
+            description: None,
+            example: Some("string"),
+            name: "signed 8-bits integer".to_string(),
+            kind: super::SchemaKind::String,
+        }
+    }
+}
+
+impl<'a> super::HasSchema for String {
+    fn schema() -> super::Schema<Self> {
+        super::Schema {
+            min_value: None,
+            max_value: None,
+            description: None,
+            example: Some("string".to_string()),
+            name: "signed 8-bits integer".to_string(),
+            kind: super::SchemaKind::String,
+        }
+    }
+}

core/lib/src/doc/mod.rs

@@ -0,0 +1,48 @@
+//! Traits and structs related to automagically generating documentation for your Rocket routes
+
+use std::{collections::HashMap, marker::PhantomData};
+
+use rocket_http::ContentType;
+
+mod has_schema;
+
+#[derive(Default)]
+pub struct Docs(HashMap<ContentType, DocContent>);
+
+#[derive(Default)]
+pub struct DocContent {
+    title: Option<String>,
+    description: Option<String>,
+    content_type: Option<String>,
+}
+
+pub struct Resolve<T: ?Sized>(PhantomData<T>);
+
+pub trait Documented {
+    fn docs() -> Docs;
+}
+
+trait Undocumented {
+    fn docs() -> Docs {
+        Docs::default()
+    }
+}
+
+impl<T: ?Sized> Undocumented for T { }
+
+impl<T: Documented + ?Sized> Resolve<T> {
+    pub const DOCUMENTED: bool = true;
+
+    pub fn docs() -> Docs {
+        T::docs()
+    }
+}
+
+// impl<T: Documented + ?Sized> Documented for Json<T> {
+//     fn docs() -> Docs {
+//         Docs {
+//             content_type: Some("application/json".to_string()),
+//             ..Self::docs()
+//         }
+//     }
+// }

core/lib/src/lib.rs

@@ -124,6 +124,7 @@ pub mod fairing;
 pub mod error;
 pub mod catcher;
 pub mod route;
+pub mod doc;
 
 // Reexport of HTTP everything.
 pub mod http {

core/lib/src/route/route.rs

@@ -190,6 +190,8 @@ pub struct Route {
     pub format: Option<MediaType>,
     /// The discovered sentinels.
     pub(crate) sentinels: Vec<Sentry>,
+    /// The route's docstring, which may be empty.
+    pub docstring: String,
 }
 
 impl Route {
@@ -253,6 +255,7 @@ impl Route {
             sentinels: Vec::new(),
             handler: Box::new(handler),
             rank, uri, method,
+            docstring: String::new(),
         }
     }
 
@@ -345,6 +348,9 @@ pub struct StaticInfo {
     /// Route-derived sentinels, if any.
     /// This isn't `&'static [SentryInfo]` because `type_name()` isn't `const`.
     pub sentinels: Vec<Sentry>,
+    /// The doc comment associated with this route.
+    pub docstring: String,
+
 }
 
 #[doc(hidden)]
@@ -361,6 +367,7 @@ impl From<StaticInfo> for Route {
             format: info.format,
             sentinels: info.sentinels.into_iter().collect(),
             uri,
+            docstring: info.docstring,
         }
     }
 }