Refactor AuthMonitor::update() to simplify implementation

Author: FastAlien

src/auth_monitor.rs

@@ -14,6 +14,12 @@ pub struct AuthMonitor {
     last_failed_auth_timestamp: i64,
 }
 
+#[derive(PartialEq, Debug)]
+pub enum AuthState {
+    AuthFailureLimitNotReached,
+    AuthFailureLimitReached,
+}
+
 impl AuthMonitor {
     pub fn new(params: AuthMonitorParams) -> Result<AuthMonitor, Box<dyn Error>> {
         params.validate()?;
@@ -26,7 +32,7 @@ impl AuthMonitor {
         });
     }
 
-    pub fn update(&mut self, on_max_failed_attempts: impl FnOnce()) {
+    pub fn update(&mut self) -> AuthState {
         if self.should_reset_failed_attempts() {
             self.reset_failed_attempts();
         }
@@ -59,8 +65,10 @@ impl AuthMonitor {
         });
 
         if failed_attempts > 0 {
-            self.increase_failed_attempts(failed_attempts, on_max_failed_attempts);
+            return self.increase_failed_attempts(failed_attempts);
         }
+
+        return AuthState::AuthFailureLimitNotReached;
     }
 
     fn should_reset_failed_attempts(&self) -> bool {
@@ -82,17 +90,14 @@ impl AuthMonitor {
         self.last_failed_auth_timestamp = 0;
     }
 
-    fn increase_failed_attempts(
-        &mut self,
-        failed_attempts: i32,
-        on_max_failed_attempts: impl FnOnce(),
-    ) {
+    fn increase_failed_attempts(&mut self, failed_attempts: i32) -> AuthState {
         self.failed_attempts += failed_attempts;
         println!("Authentication failed {} time(s)", self.failed_attempts);
         if self.failed_attempts >= self.options.max_failed_attempts {
             println!("Authentication fail limit reached, shutting down");
-            on_max_failed_attempts();
+            return AuthState::AuthFailureLimitReached;
         }
+        return AuthState::AuthFailureLimitNotReached;
     }
 }
 

src/auth_monitor_tests.rs

@@ -2,7 +2,7 @@ use std::ops::Range;
 use std::thread::sleep;
 use std::time::Duration;
 
-use crate::auth_monitor::AuthMonitor;
+use crate::auth_monitor::{AuthMonitor, AuthState};
 use crate::auth_monitor_options::AuthMonitorOptions;
 use crate::auth_monitor_params::AuthMonitorParams;
 use crate::test_utils::test_file::TestFile;
@@ -22,18 +22,12 @@ impl AuthMonitorTest {
         return AuthMonitorTest { auth_monitor };
     }
 
-    pub fn expect_no_update_callback_call(&mut self) {
-        self.auth_monitor.update(|| {
-            panic!("Callback call was not expected");
-        });
+    pub fn expect_auth_failure_limit_not_reached(&mut self) {
+        assert_eq!(self.auth_monitor.update(), AuthState::AuthFailureLimitNotReached);
     }
 
-    pub fn expect_update_callback_is_called_once(&mut self) {
-        let mut call_count = 0;
-        self.auth_monitor.update(|| {
-            call_count += 1;
-        });
-        assert_eq!(call_count, 1, "One callback call was expected")
+    pub fn expect_auth_failure_limit_reached(&mut self) {
+        assert_eq!(self.auth_monitor.update(), AuthState::AuthFailureLimitReached);
     }
 }
 
@@ -46,17 +40,17 @@ fn when_file_does_not_exist_then_changes_are_monitored_after_it_is_created() {
 
     let options = AuthMonitorOptions::default();
     let mut test = AuthMonitorTest::new(file.path(), options);
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     file.create();
 
     for i in 0usize..(options.max_failed_attempts - 1) as usize {
         file.write_auth_failed_message(i);
-        test.expect_no_update_callback_call();
+        test.expect_auth_failure_limit_not_reached();
     }
 
     file.write_auth_failed_message(0);
-    test.expect_update_callback_is_called_once();
+    test.expect_auth_failure_limit_reached();
 }
 
 #[test]
@@ -68,20 +62,20 @@ pub fn when_auth_failure_limit_is_reached_then_update_callback_is_invoked() {
             ..AuthMonitorOptions::default()
         };
         let mut test = AuthMonitorTest::new(file.path(), options);
-        test.expect_no_update_callback_call();
+        test.expect_auth_failure_limit_not_reached();
 
         for i in 0usize..(max_failed_attempts - 1) as usize {
             file.write_auth_failed_message(i);
-            test.expect_no_update_callback_call();
+            test.expect_auth_failure_limit_not_reached();
         }
 
         for i in 0usize..(max_failed_attempts * 2) as usize {
             file.write_other_message(i);
-            test.expect_no_update_callback_call();
+            test.expect_auth_failure_limit_not_reached();
         }
 
         file.write_auth_failed_message(0);
-        test.expect_update_callback_is_called_once();
+        test.expect_auth_failure_limit_reached();
     }
 }
 
@@ -94,12 +88,12 @@ pub fn when_auth_failure_limit_is_reached_between_updates_then_next_update_invok
             ..AuthMonitorOptions::default()
         };
         let mut test = AuthMonitorTest::new(file.path(), options);
-        test.expect_no_update_callback_call();
+        test.expect_auth_failure_limit_not_reached();
 
         file.write_auth_failed_messages(max_failed_attempts as usize);
         file.write_other_messages(max_failed_attempts as usize);
 
-        test.expect_update_callback_is_called_once();
+        test.expect_auth_failure_limit_reached();
     }
 }
 
@@ -111,13 +105,13 @@ pub fn when_reset_time_has_passed_then_reset_failed_attempt_counter() {
         ..AuthMonitorOptions::default()
     };
     let mut test = AuthMonitorTest::new(file.path(), options);
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     let failed_attempts_safe_limit = (options.max_failed_attempts - 1) as usize;
 
     for i in 0usize..failed_attempts_safe_limit {
         file.write_auth_failed_message(i);
-        test.expect_no_update_callback_call();
+        test.expect_auth_failure_limit_not_reached();
     }
 
     let sleep_duration = Duration::from_secs((options.reset_after_seconds + 1) as u64);
@@ -126,11 +120,11 @@ pub fn when_reset_time_has_passed_then_reset_failed_attempt_counter() {
 
     for i in 0usize..failed_attempts_safe_limit {
         file.write_auth_failed_message(i);
-        test.expect_no_update_callback_call();
+        test.expect_auth_failure_limit_not_reached();
     }
 
     file.write_auth_failed_message(0);
-    test.expect_update_callback_is_called_once();
+    test.expect_auth_failure_limit_reached();
 }
 
 #[test]
@@ -141,16 +135,16 @@ pub fn when_ignore_subsequent_fails_duration_has_not_elapsed_then_update_callbac
         ..AuthMonitorOptions::default()
     };
     let mut test = AuthMonitorTest::new(file.path(), options);
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     let max_failed_attempts = options.max_failed_attempts as usize;
 
     for i in 0usize..max_failed_attempts {
         file.write_auth_failed_message(i);
-        test.expect_no_update_callback_call();
+        test.expect_auth_failure_limit_not_reached();
     }
 
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 }
 
 #[test]
@@ -161,7 +155,7 @@ pub fn when_ignore_subsequent_fails_duration_has_elapsed_then_update_callback_is
         ..AuthMonitorOptions::default()
     };
     let mut test = AuthMonitorTest::new(file.path(), options);
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     let max_failed_attempts = options.max_failed_attempts as usize;
     let sleep_duration = Duration::from_millis((options.ignore_subsequent_fails_ms + 1) as u64);
@@ -172,7 +166,7 @@ pub fn when_ignore_subsequent_fails_duration_has_elapsed_then_update_callback_is
         sleep(sleep_duration);
     }
 
-    test.expect_update_callback_is_called_once();
+    test.expect_auth_failure_limit_reached();
 }
 
 #[test]
@@ -181,13 +175,13 @@ fn when_file_is_deleted_and_new_one_is_created_then_changes_are_still_monitored(
     let options = AuthMonitorOptions::default();
     let mut test = AuthMonitorTest::new(file.path(), options);
     file.remove();
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     file.create();
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     file.write_auth_failed_messages(options.max_failed_attempts as usize);
-    test.expect_update_callback_is_called_once();
+    test.expect_auth_failure_limit_reached();
 }
 
 #[test]
@@ -199,12 +193,12 @@ fn when_file_is_renamed_and_new_one_is_created_then_changes_are_still_monitored(
     let filepath = String::from(file.path());
     let new_filepath = format!("{}.bak", file.path());
     file.rename(&new_filepath);
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     let mut new_file = TestFile::new(&filepath);
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
     new_file.write_auth_failed_messages(options.max_failed_attempts as usize);
-    test.expect_update_callback_is_called_once();
+    test.expect_auth_failure_limit_reached();
 }
 
 #[test]
@@ -216,8 +210,8 @@ fn when_file_is_truncated_then_changes_are_still_monitored() {
     let mut test = AuthMonitorTest::new(file.path(), options);
 
     file.truncate();
-    test.expect_no_update_callback_call();
+    test.expect_auth_failure_limit_not_reached();
 
     file.write_auth_failed_messages(options.max_failed_attempts as usize);
-    test.expect_update_callback_is_called_once();
+    test.expect_auth_failure_limit_reached();
 }

src/main.rs

@@ -8,7 +8,7 @@ use std::{env, thread};
 use signal_hook::consts::{SIGABRT, SIGINT};
 use signal_hook::iterator::Signals;
 
-use crate::auth_monitor::AuthMonitor;
+use crate::auth_monitor::{AuthMonitor, AuthState};
 use crate::auth_monitor_params::AuthMonitorParams;
 
 mod auth_file_reader;
@@ -56,7 +56,9 @@ fn start_monitoring(params: AuthMonitorParams) -> ExitCode {
         }
     };
     loop {
-        auth_monitor.update(shutdown);
+        if let AuthState::AuthFailureLimitReached = auth_monitor.update() {
+            shutdown();
+        }
         match signals.pending().next() {
             Some(signal) => {
                 println!("Received signal {}", signal);