feat: create reactive traits (AsReactive and ReactiveCapture)

Cargo.lock

@@ -2159,6 +2159,7 @@ version = "0.1.0"
 dependencies = [
  "quote",
  "syn",
+ "traits",
 ]
 
 [[package]]
@@ -2960,6 +2961,7 @@ dependencies = [
  "serde",
  "serde_dynamo",
  "tokio",
+ "traits",
  "url",
  "uuid",
  "wasm-bindgen",
@@ -3645,6 +3647,13 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "traits"
+version = "0.1.0"
+dependencies = [
+ "leptos",
+]
+
 [[package]]
 name = "try-lock"
 version = "0.2.5"

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "scholarships-rs"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 [lib]
 crate-type = ["cdylib", "rlib"]
@@ -24,6 +24,7 @@ leptos_oidc = "0.9.0"
 url = "2.5.4"
 
 macros = { path = "./macros" }
+traits = { path = "./traits" }
 
 [features]
 hydrate = [

macros/Cargo.toml

@@ -8,4 +8,6 @@ proc-macro = true
 
 [dependencies]
 syn = "2.0"
-quote = "1.0"
+quote = "1.0"
+
+traits = { path = "../traits" }

macros/src/lib.rs

@@ -1,7 +1,72 @@
 use proc_macro::TokenStream;
 use quote::quote;
-use syn::{Data, Ident, parse_macro_input};
+use syn::{parse_macro_input, Data, Ident};
 
+/// Derives the `AsReactive` and `ReactiveCapture` traits for a struct, while also
+/// providing a new reactive struct with the same field names, but they are wrapped
+/// in the Leptos `RwSignal`.
+///
+/// Fields that are custom types are not automatically converted into reactive types. They
+/// will be wrapped in an `RwSignal` struct, but that is where this process stops. Making
+/// other information reactive must be implemented manually.
+///
+/// For example, when the `Reactive` macro is expanded for the struct `User`, it will look
+/// like this:
+///
+/// ```
+/// #[derive(Reactive)]
+/// struct User {
+///     id: i32,
+///     name: String,
+///     custom: CustomType
+/// }
+///
+/// // This code will be added:
+/// struct UserReactive {
+///     id: RwSignal<i32>,
+///     name: RwSignal<String>,
+///     custom: RwSignal<CustomType>
+/// }
+///
+/// impl AsReactive for User {
+///     type ReactiveType = UserReactive;
+///     // Other methods - refer to AsReactive documentation.
+/// }
+///
+/// impl ReactiveCapture for UserReactive {
+///     type CaptureType = User;
+///     // Other methods - refer to ReactiveCapture documentation.
+/// }
+/// ```
+///
+/// The base type (`User`) can then be converted into the reactive type:
+/// ```
+/// let user = User::new();
+/// let user_reactive = user.as_reactive();
+/// ```
+/// And captured back into a non-reactive type:
+/// ```
+/// let captured_user = user_reactive.capture()
+/// ```
+///
+/// # Important Considerations
+///
+/// A reminder that custom types, in this case `CustomType`, are just wrapped in an `RwSignal`.
+/// They are not automatically converted to their own `Reactive` type in the case that they
+/// derive this macro. As a result, custom reactive types *must* be updated manually by utilizing
+/// the `RwSignal::update` and `RwSignal::set` methods.
+///
+/// For example, the `UserReactive` struct from earlier does not convert the `CustomType` into a
+/// `CustomTypeReactive`. We have to do that ourselves:
+/// ```
+/// let user: User = User::new();
+/// let user_reactive: UserReactive = user.as_reactive();
+/// let custom_reactive: CustomTypeReactive = user_reactive.custom.as_reactive();
+/// // And then convert back...
+/// user_reactive.custom.set(custom_reactive.capture());
+/// ```
+/// If a shorthand for the `capture` and `as_reactive` functions are absolutely *required*, then this
+/// macro is probably not the way to go - as of now, this functionality should be impmlemented manually.
 #[proc_macro_derive(Reactive)]
 pub fn make_reactive(input: TokenStream) -> TokenStream {
     let input = parse_macro_input!(input as syn::DeriveInput);
@@ -32,7 +97,7 @@ pub fn make_reactive(input: TokenStream) -> TokenStream {
 
         // Create new function arguments/inits
         let new_fn_arg = quote! {
-            #field_name: _RwSignal::new(data.#field_name),
+            #field_name: _RwSignal::new(self.#field_name),
         };
 
         let from_fn_arg = quote! {
@@ -43,30 +108,36 @@ pub fn make_reactive(input: TokenStream) -> TokenStream {
         from_fn_args.push(from_fn_arg);
     }
 
-    let reactive_docs = format!("Reactive version of the [`{name}`] struct. Automatically created by the `Reactive` macro.");
+    let reactive_docs = format!(
+        "Reactive version of the [`{name}`] struct. Automatically created by the `Reactive` macro."
+    );
 
     // Expand the macro. The output is a struct with new reactive fields and a new function,
     // which initializes the reactive fields based on the original struct's fields.
     let expanded = quote! {
         use leptos::prelude::RwSignal as _RwSignal;  // in case the user imports it themselves
         use leptos::prelude::GetUntracked as _;
+        use traits::{AsReactive, ReactiveCapture};
 
         #[doc = #reactive_docs]
         pub struct #reactive_name {
             #(#new_fields)*
         }
 
-        impl #reactive_name {
-            /// Creates a new `#reactive_name` struct from a non-reactive `#name`.
-            pub fn new(data: #name) -> Self {
-                Self {
+        impl AsReactive for #name {
+            type ReactiveType = #reactive_name;
+
+            fn as_reactive(self) -> Self::ReactiveType {
+                #reactive_name {
                     #(#new_fn_args)*
                 }
             }
+        }
 
-            /// Captures the information of this struct into a `#name` struct, for use
-            /// in server functions.
-            pub fn capture(&self) -> #name {
+        impl ReactiveCapture for #reactive_name {
+            type CaptureType = #name;
+
+            fn capture(&self) -> Self::CaptureType {
                 #name {
                     #(#from_fn_args)*
                 }

src/components/multi_entry.rs

@@ -2,10 +2,11 @@ use std::collections::HashMap;
 
 use crate::components::ActionButton;
 use leptos::prelude::*;
+use macros::Reactive;
 use serde::{Deserialize, Serialize};
 use uuid::Uuid;
 
-#[derive(Clone, Serialize, Deserialize, Debug)]
+#[derive(Clone, Serialize, Deserialize, Debug, Reactive, Default)]
 pub struct MultiEntryData {
     pub id: Uuid,
     pub data: HashMap<String, ValueType>,
@@ -130,27 +131,31 @@ pub fn MultiEntry(
             <div class="rounded-md bg-red-700">
                 // This div MUST have the same spacing CSS as the main entry div
                 <div class="flex bg-inherit p-3 m-1">
-                    <span class="flex-1 text-white font-bold">{name_member.get().display_name}</span>
-                    <span class="flex-1 text-white font-bold">{info_member.get().display_name}</span>
+                    <span class="flex-1 text-white font-bold">
+                        {name_member.get().display_name}
+                    </span>
+                    <span class="flex-1 text-white font-bold">
+                        {info_member.get().display_name}
+                    </span>
                 </div>
             </div>
             // Entry section
             <div>
                 <For
-                    each = move || entries.get()
-                    key = |entry: &MultiEntryData| entry.id
-                    children = move |entry| view! {
-                        <Entry
-                            entry_data=entry.clone()
-                            name_member=name_member
-                            info_member=info_member
-                        />
+                    each=move || entries.get()
+                    key=|entry: &MultiEntryData| entry.id
+                    children=move |entry| {
+                        view! {
+                            <Entry
+                                entry_data=entry.clone()
+                                name_member=name_member
+                                info_member=info_member
+                            />
+                        }
                     }
                 />
             </div>
         </div>
-        <ActionButton on:click=create_entry>
-            Add Entry
-        </ActionButton>
+        <ActionButton on:click=create_entry>Add Entry</ActionButton>
     }
 }

src/pages/home_page.rs

@@ -6,7 +6,7 @@ use aws_sdk_dynamodb::{error::ProvideErrorMetadata, types::AttributeValue, Clien
 use serde_dynamo::{from_item, to_item};
 
 use crate::app::Unauthenticated;
-use crate::common::{StudentInfo, StudentInfoReactive, UserClaims};
+use crate::common::{StudentInfo, UserClaims};
 use crate::components::{
     ActionButton, CheckboxList, Loading, OutlinedTextField, Panel, Row, Select,
     RadioList
@@ -14,6 +14,7 @@ use crate::components::{
 use leptos::leptos_dom::logging::console_log;
 use leptos::prelude::*;
 use leptos_oidc::{Algorithm, AuthLoaded, AuthSignal, Authenticated};
+use traits::{AsReactive, ReactiveCapture};
 
 #[server(GetSubmission, endpoint = "/get-submission")]
 pub async fn get_submission(id: String) -> Result<StudentInfo, ServerFnError> {
@@ -119,7 +120,7 @@ pub fn HomePage() -> impl IntoView {
                         server_resource
                             .get()
                             .map(|submission: StudentInfo| {
-                                let reactive_info = StudentInfoReactive::new(submission);
+                                let reactive_info = submission.as_reactive();
                                 let select_value = RwSignal::new(String::from("Math"));
                                 let chk_select = RwSignal::new(vec!["Testing 2".into()]);
                                 let elements_disabled = RwSignal::new(false);

traits/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "traits"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+leptos = { version = "0.8" }

traits/src/lib.rs

@@ -0,0 +1,3 @@
+pub mod reactive;
+
+pub use reactive::*;

traits/src/reactive.rs

@@ -0,0 +1,82 @@
+/// Trait that ensures a reactive struct can be created from a non-reactive struct.
+///
+/// For example:
+///
+/// ```rust
+/// struct User {
+///     id: i32,
+///     name: String
+/// }
+///
+/// struct UserReactive {
+///     id: RwSignal<i32>,
+///     name: RwSignal<String>
+/// }
+///
+/// impl ReactiveCapture for UserReactive {
+///     // implement - required for ReactiveType.
+/// }
+///
+/// impl AsReactive for User {
+///     type ReactiveType = UserReactive;
+///     fn as_reactive(self) -> UserReactive {
+///         UserReactive {
+///             id: RwSignal::new(self.id),
+///             name: RwSignal::new(self.name)
+///         }
+///     }
+/// }
+/// ```
+pub trait AsReactive {
+    /// The type of the reactive struct. It must implement `ReactiveCapture`.
+    type ReactiveType: ReactiveCapture;
+
+    /// Wraps all fields of the struct into an `RwSignal`, returning a new
+    /// "reactive" struct.
+    ///
+    /// Note that this method consumes the original struct and returns a new
+    /// reactive struct.
+    fn as_reactive(self) -> Self::ReactiveType;
+}
+
+/// Trait that ensures a reactive struct can be captured into a non-reactive struct.
+/// The "captured" struct does not contain *any* reactive fields, meaning that it is not
+/// wrapped in an `RwSignal`.
+///
+/// The captured struct should simply collect all the values from the reactive fields at
+/// that point in time.
+///
+/// For example:
+///
+/// ```rust
+/// struct User {
+///     id: i32,
+///     name: String
+/// }
+///
+/// struct UserReactive {
+///     id: RwSignal<i32>,
+///     name: RwSignal<String>
+/// }
+///
+/// impl AsReactive for User {
+///     // implement - required for CaptureType.
+/// }
+///
+/// impl ReactiveCapture for UserReactive {
+///     type CaptureType = User;
+///     fn capture(self) -> User {
+///         User {
+///             id: self.id.get(),
+///             name: self.name.get()
+///         }
+///     }
+/// }
+/// ```
+pub trait ReactiveCapture {
+    /// The type of the captured struct. It must implement `AsReactive`.
+    type CaptureType: AsReactive;
+
+    /// Captures the current state of the reactive struct into a non-reactive struct.
+    fn capture(&self) -> Self::CaptureType;
+}