pattern: Implement Health Check for Microservices Observability (#2695) (#2774)

* Add Health Check pattern implementation The commit introduces Health Check pattern, providing a series of health indicators for system performance and stability monitoring, including checks for system CPU load, process CPU load, database health, memory usage, and garbage collection metrics. It also includes asynchronous execution and caching mechanisms for health checks, and retry configurations for resilience. Implements health checking components as per issue #2695. * Test cases and javadoc for HealthEndpointIntegrationTest * Added more log to test case to see why it returns 503 * Change config values to see if the system High system CPU load is resolved or not in CI. * Fixes for test cases. * some fixes for Sonar. * some fixes for Sonar. ADDED HIGH_PROCESS_CPU_LOAD_MESSAGE_WITHOUT_PARAM ADDED HIGH_SYSTEM_CPU_LOAD_MESSAGE_WITHOUT_PARAM * Sonar fixes address "Define and throw a dedicated exception instead of using a generic one." added HealthCheckInterruptedException refactored CustomHealthIndicator * fixes checkstyle violation.
2026-05-15 18:59:10 +00:00 · 2023-12-02 15:17:01 +03:00
parent 83dba617c5
commit 21f7b026f5
27 changed files with 2382 additions and 0 deletions
@@ -0,0 +1,128 @@
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyLong;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import com.iluwatar.health.check.AsynchronousHealthChecker;
+import com.iluwatar.health.check.MemoryHealthIndicator;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.function.Supplier;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.boot.actuate.health.Health;
+import org.springframework.boot.actuate.health.Status;
+
+/**
+ * Unit tests for {@link MemoryHealthIndicator}.
+ *
+ * @author ydoksanbir
+ */
+@ExtendWith(MockitoExtension.class)
+class MemoryHealthIndicatorTest {
+
+  /** Mocked AsynchronousHealthChecker instance. */
+  @Mock private AsynchronousHealthChecker asynchronousHealthChecker;
+
+  /** `MemoryHealthIndicator` instance to be tested. */
+  @InjectMocks private MemoryHealthIndicator memoryHealthIndicator;
+
+  /**
+   * Test case for the `health()` method when memory usage is below the threshold.
+   *
+   * <p>Asserts that when the `health()` method is called and memory usage is below the threshold,
+   * it returns a Health object with Status.UP.
+   */
+  @Test
+  void whenMemoryUsageIsBelowThreshold_thenHealthIsUp() {
+    // Arrange
+    CompletableFuture<Health> future =
+        CompletableFuture.completedFuture(
+            Health.up().withDetail("memory usage", "50% of max").build());
+    when(asynchronousHealthChecker.performCheck(any(Supplier.class), anyLong())).thenReturn(future);
+
+    // Act
+    Health health = memoryHealthIndicator.health();
+
+    // Assert
+    assertEquals(Status.UP, health.getStatus());
+    assertEquals("50% of max", health.getDetails().get("memory usage"));
+  }
+
+  /**
+   * Test case for the `health()` method when memory usage is above the threshold.
+   *
+   * <p>Asserts that when the `health()` method is called and memory usage is above the threshold,
+   * it returns a Health object with Status.DOWN.
+   */
+  @Test
+  void whenMemoryUsageIsAboveThreshold_thenHealthIsDown() {
+    // Arrange
+    CompletableFuture<Health> future =
+        CompletableFuture.completedFuture(
+            Health.down().withDetail("memory usage", "95% of max").build());
+    when(asynchronousHealthChecker.performCheck(any(Supplier.class), anyLong())).thenReturn(future);
+
+    // Act
+    Health health = memoryHealthIndicator.health();
+
+    // Assert
+    assertEquals(Status.DOWN, health.getStatus());
+    assertEquals("95% of max", health.getDetails().get("memory usage"));
+  }
+
+  /**
+   * Test case for the `health()` method when the health check is interrupted.
+   *
+   * <p>Asserts that when the `health()` method is called and the health check is interrupted, it
+   * returns a Health object with Status DOWN and an error detail indicating the interruption.
+   *
+   * @throws ExecutionException if the future fails to complete
+   * @throws InterruptedException if the thread is interrupted while waiting for the future to
+   *     complete
+   */
+  @Test
+  void whenHealthCheckIsInterrupted_thenHealthIsDown()
+      throws ExecutionException, InterruptedException {
+    // Arrange
+    CompletableFuture<Health> future = mock(CompletableFuture.class);
+    when(asynchronousHealthChecker.performCheck(any(Supplier.class), anyLong())).thenReturn(future);
+    // Simulate InterruptedException when future.get() is called
+    when(future.get()).thenThrow(new InterruptedException("Health check interrupted"));
+
+    // Act
+    Health health = memoryHealthIndicator.health();
+
+    // Assert
+    assertEquals(Status.DOWN, health.getStatus());
+    String errorDetail = (String) health.getDetails().get("error");
+    assertNotNull(errorDetail);
+    assertTrue(errorDetail.contains("Health check interrupted"));
+  }
+
+  /**
+   * Test case for the `health()` method when the health check execution fails.
+   *
+   * <p>Asserts that when the `health()` method is called and the health check execution fails, it
+   * returns a Health object with Status DOWN and an error detail indicating the failure.
+   */
+  @Test
+  void whenHealthCheckExecutionFails_thenHealthIsDown() {
+    // Arrange
+    CompletableFuture<Health> future = new CompletableFuture<>();
+    future.completeExceptionally(
+        new ExecutionException(new RuntimeException("Service unavailable")));
+    when(asynchronousHealthChecker.performCheck(any(Supplier.class), anyLong())).thenReturn(future);
+
+    // Act
+    Health health = memoryHealthIndicator.health();
+
+    // Assert
+    assertEquals(Status.DOWN, health.getStatus());
+    assertTrue(health.getDetails().get("error").toString().contains("Service unavailable"));
+  }
+}