Added documentation and examples for the init() callback

Author: ElFantasma

concurrency/src/tasks/gen_server.rs

@@ -146,6 +146,9 @@ where
         }
     }
 
+    /// Initialization function. It's called before main loop. It
+    /// can be overrided on implementations in case initial steps are
+    /// required.
     fn init(
         &mut self,
         _handle: &GenServerHandle<Self>,

concurrency/src/threads/gen_server.rs

@@ -119,6 +119,9 @@ where
         }
     }
 
+    /// Initialization function. It's called before main loop. It
+    /// can be overrided on implementations in case initial steps are
+    /// required.
     fn init(
         &mut self,
         _handle: &GenServerHandle<Self>,

examples/bank/src/main.rs

@@ -31,18 +31,33 @@ use spawned_rt::tasks as rt;
 
 fn main() {
     rt::run(async {
+        // Starting the bank
         let mut name_server = Bank::start(HashMap::new());
 
+        // Testing initial balance for "main" account
+        let result = Bank::withdraw(&mut name_server, "main".to_string(), 15).await;
+        tracing::info!("Withdraw result {result:?}");
+        assert_eq!(
+            result,
+            Ok(BankOutMessage::WidrawOk {
+                who: "main".to_string(),
+                amount: 985
+            })
+        );
+
         let joe = "Joe".to_string();
 
+        // Error on deposit for an unexistent account
         let result = Bank::deposit(&mut name_server, joe.clone(), 10).await;
         tracing::info!("Deposit result {result:?}");
         assert_eq!(result, Err(BankError::NotACustomer { who: joe.clone() }));
 
+        // Account creation
         let result = Bank::new_account(&mut name_server, "Joe".to_string()).await;
         tracing::info!("New account result {result:?}");
         assert_eq!(result, Ok(BankOutMessage::Welcome { who: joe.clone() }));
 
+        // Deposit
         let result = Bank::deposit(&mut name_server, "Joe".to_string(), 10).await;
         tracing::info!("Deposit result {result:?}");
         assert_eq!(
@@ -53,6 +68,7 @@ fn main() {
             })
         );
 
+        // Deposit
         let result = Bank::deposit(&mut name_server, "Joe".to_string(), 30).await;
         tracing::info!("Deposit result {result:?}");
         assert_eq!(
@@ -63,6 +79,7 @@ fn main() {
             })
         );
 
+        // Withdrawal
         let result = Bank::withdraw(&mut name_server, "Joe".to_string(), 15).await;
         tracing::info!("Withdraw result {result:?}");
         assert_eq!(
@@ -73,6 +90,7 @@ fn main() {
             })
         );
 
+        // Withdrawal with not enough balance
         let result = Bank::withdraw(&mut name_server, "Joe".to_string(), 45).await;
         tracing::info!("Withdraw result {result:?}");
         assert_eq!(
@@ -83,6 +101,7 @@ fn main() {
             })
         );
 
+        // Full withdrawal
         let result = Bank::withdraw(&mut name_server, "Joe".to_string(), 25).await;
         tracing::info!("Withdraw result {result:?}");
         assert_eq!(
@@ -93,6 +112,7 @@ fn main() {
             })
         );
 
+        // Stopping the bank
         let result = Bank::stop(&mut name_server).await;
         tracing::info!("Stop result {result:?}");
         assert_eq!(result, Ok(BankOutMessage::Stopped));

examples/bank/src/server.rs

@@ -51,6 +51,16 @@ impl GenServer for Bank {
         Self {}
     }
 
+    // Initializing "main" account with 1000 in balance to test init() callback.
+    async fn init(
+        &mut self,
+        _handle: &GenServerHandle<Self>,
+        mut state: Self::State,
+    ) -> Result<Self::State, Self::Error> {
+        state.insert("main".to_string(), 1000);
+        Ok(state)
+    }
+
     async fn handle_call(
         &mut self,
         message: Self::CallMsg,

examples/bank_threads/src/main.rs

@@ -31,18 +31,33 @@ use spawned_rt::threads as rt;
 
 fn main() {
     rt::run(|| {
+        // Starting the bank
         let mut name_server = Bank::start(HashMap::new());
 
+        // Testing initial balance for "main" account
+        let result = Bank::withdraw(&mut name_server, "main".to_string(), 15);
+        tracing::info!("Withdraw result {result:?}");
+        assert_eq!(
+            result,
+            Ok(BankOutMessage::WidrawOk {
+                who: "main".to_string(),
+                amount: 985
+            })
+        );
+
         let joe = "Joe".to_string();
 
+        // Error on deposit for an unexistent account
         let result = Bank::deposit(&mut name_server, joe.clone(), 10);
         tracing::info!("Deposit result {result:?}");
         assert_eq!(result, Err(BankError::NotACustomer { who: joe.clone() }));
 
+        // Account creation
         let result = Bank::new_account(&mut name_server, "Joe".to_string());
         tracing::info!("New account result {result:?}");
         assert_eq!(result, Ok(BankOutMessage::Welcome { who: joe.clone() }));
 
+        // Deposit
         let result = Bank::deposit(&mut name_server, "Joe".to_string(), 10);
         tracing::info!("Deposit result {result:?}");
         assert_eq!(
@@ -53,6 +68,7 @@ fn main() {
             })
         );
 
+        // Deposit
         let result = Bank::deposit(&mut name_server, "Joe".to_string(), 30);
         tracing::info!("Deposit result {result:?}");
         assert_eq!(
@@ -63,6 +79,7 @@ fn main() {
             })
         );
 
+        // Withdrawal
         let result = Bank::withdraw(&mut name_server, "Joe".to_string(), 15);
         tracing::info!("Withdraw result {result:?}");
         assert_eq!(
@@ -73,6 +90,7 @@ fn main() {
             })
         );
 
+        // Withdrawal with not enough balance
         let result = Bank::withdraw(&mut name_server, "Joe".to_string(), 45);
         tracing::info!("Withdraw result {result:?}");
         assert_eq!(
@@ -83,6 +101,7 @@ fn main() {
             })
         );
 
+        // Full withdrawal
         let result = Bank::withdraw(&mut name_server, "Joe".to_string(), 25);
         tracing::info!("Withdraw result {result:?}");
         assert_eq!(
@@ -93,6 +112,7 @@ fn main() {
             })
         );
 
+        // Stopping the bank
         let result = Bank::stop(&mut name_server);
         tracing::info!("Stop result {result:?}");
         assert_eq!(result, Ok(BankOutMessage::Stopped));

examples/bank_threads/src/server.rs

@@ -47,6 +47,16 @@ impl GenServer for Bank {
         Self {}
     }
 
+    // Initializing "main" account with 1000 in balance to test init() callback.
+    fn init(
+        &mut self,
+        _handle: &GenServerHandle<Self>,
+        mut state: Self::State,
+    ) -> Result<Self::State, Self::Error> {
+        state.insert("main".to_string(), 1000);
+        Ok(state)
+    }
+
     fn handle_call(
         &mut self,
         message: Self::CallMsg,