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.
2026-05-31 14:17:11 +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 +1,123 @@
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.when;
+
+import com.iluwatar.health.check.CpuHealthIndicator;
+import com.sun.management.OperatingSystemMXBean;
+import java.lang.reflect.Field;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+import org.springframework.boot.actuate.health.Health;
+import org.springframework.boot.actuate.health.Status;
+
+/**
+ * Test class for the {@link CpuHealthIndicator} class.
+ *
+ * @author ydoksanbir
+ */
+class CpuHealthIndicatorTest {
+
+  /** The CPU health indicator to be tested. */
+  private CpuHealthIndicator cpuHealthIndicator;
+
+  /** The mocked operating system MXBean used to simulate CPU health information. */
+  private OperatingSystemMXBean mockOsBean;
+
+  /**
+   * Sets up the test environment before each test method.
+   *
+   * <p>Mocks the {@link OperatingSystemMXBean} and sets it in the {@link CpuHealthIndicator}
+   * instance.
+   */
+  @BeforeEach
+  void setUp() {
+    // Mock the com.sun.management.OperatingSystemMXBean
+    mockOsBean = Mockito.mock(com.sun.management.OperatingSystemMXBean.class);
+    cpuHealthIndicator = new CpuHealthIndicator();
+    setOperatingSystemMXBean(cpuHealthIndicator, mockOsBean);
+  }
+
+  /**
+   * Reflection method to set the private osBean in CpuHealthIndicator.
+   *
+   * @param indicator The CpuHealthIndicator instance to set the osBean for.
+   * @param osBean The OperatingSystemMXBean to set.
+   */
+  private void setOperatingSystemMXBean(
+      CpuHealthIndicator indicator, OperatingSystemMXBean osBean) {
+    try {
+      Field osBeanField = CpuHealthIndicator.class.getDeclaredField("osBean");
+      osBeanField.setAccessible(true);
+      osBeanField.set(indicator, osBean);
+    } catch (NoSuchFieldException | IllegalAccessException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  /**
+   * Tests that the health status is DOWN when the system CPU load is high.
+   *
+   * <p>Sets the system CPU load to 90% and mocks the other getters to return appropriate values.
+   * Executes the health check and asserts that the health status is DOWN and the error message
+   * indicates high system CPU load.
+   */
+  @Test
+  void whenSystemCpuLoadIsHigh_thenHealthIsDown() {
+    // Set thresholds for testing within the test method to avoid issues with Spring's @Value
+    cpuHealthIndicator.setSystemCpuLoadThreshold(80.0);
+    cpuHealthIndicator.setProcessCpuLoadThreshold(50.0);
+    cpuHealthIndicator.setLoadAverageThreshold(0.75);
+
+    // Mock the getters to return your desired values
+    when(mockOsBean.getCpuLoad()).thenReturn(0.9); // Simulate 90% system CPU load
+    when(mockOsBean.getAvailableProcessors()).thenReturn(8);
+    when(mockOsBean.getSystemLoadAverage()).thenReturn(9.0);
+
+    // Execute the health check
+    Health health = cpuHealthIndicator.health();
+
+    // Assertions
+    assertEquals(
+        Status.DOWN,
+        health.getStatus(),
+        "Health status should be DOWN when system CPU load is high");
+    assertEquals(
+        "High system CPU load",
+        health.getDetails().get("error"),
+        "Error message should indicate high system CPU load");
+  }
+
+  /**
+   * Tests that the health status is DOWN when the process CPU load is high.
+   *
+   * <p>Sets the process CPU load to 80% and mocks the other getters to return appropriate values.
+   * Executes the health check and asserts that the health status is DOWN and the error message
+   * indicates high process CPU load.
+   */
+  @Test
+  void whenProcessCpuLoadIsHigh_thenHealthIsDown() {
+    // Set thresholds for testing within the test method to avoid issues with Spring's @Value
+    cpuHealthIndicator.setSystemCpuLoadThreshold(80.0);
+    cpuHealthIndicator.setProcessCpuLoadThreshold(50.0);
+    cpuHealthIndicator.setLoadAverageThreshold(0.75);
+
+    // Mock the getters to return your desired values
+    when(mockOsBean.getCpuLoad()).thenReturn(0.5); // Simulate 50% system CPU load
+    when(mockOsBean.getProcessCpuLoad()).thenReturn(0.8); // Simulate 80% process CPU load
+    when(mockOsBean.getAvailableProcessors()).thenReturn(8);
+    when(mockOsBean.getSystemLoadAverage()).thenReturn(5.0);
+
+    // Execute the health check
+    Health health = cpuHealthIndicator.health();
+
+    // Assertions
+    assertEquals(
+        Status.DOWN,
+        health.getStatus(),
+        "Health status should be DOWN when process CPU load is high");
+    assertEquals(
+        "High process CPU load",
+        health.getDetails().get("error"),
+        "Error message should indicate high process CPU load");
+  }
+}