Spring Boot 生产就绪特性浅析（一）

1. Spring Boot Actuator：生产监控的基石

1.1 Actuator 架构设计

Spring Boot Actuator 采用了分层架构设计：

应用层 (Application Layer)↓
Actuator 端点层 (Endpoint Layer)↓
技术指标收集层 (Metrics Collection Layer)  ↓
外部系统集成层 (External Systems Integration)

核心组件关系图：

Spring Boot Application├── HealthEndpoint ← HealthIndicator(s)├── MetricsEndpoint ← MeterRegistry ← MeterBinders├── InfoEndpoint ← InfoContributor(s)  ├── LoggersEndpoint ← LoggingSystem├── ConfigurationPropertiesEndpoint└── Custom Endpoints

1.2 Actuator 的完整依赖配置

<!-- 核心 Actuator 依赖 -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId>
</dependency><!-- 监控系统集成 -->
<dependency><groupId>io.micrometer</groupId><artifactId>micrometer-registry-prometheus</artifactId>
</dependency>
<dependency><groupId>io.micrometer</groupId><artifactId>micrometer-registry-influx</artifactId>
</dependency><!-- 链路追踪 -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

1.3 端点安全配置策略

management:endpoints:web:exposure:include: "health,info,metrics,prometheus"exclude: "env,configprops"base-path: "/internal/actuator"jmx:exposure:include: "*"endpoint:health:enabled: trueshow-details: "when_authorized"show-components: "when_authorized"roles: "ACTUATOR_ADMIN"shutdown:enabled: falseserver:port: 8081address: "127.0.0.1"ssl:enabled: truekey-store: "classpath:keystore.p12"key-store-password: "${SSL_KEYSTORE_PASSWORD}"

2. 健康检查：多层次深度监控

2.1 健康检查的完整架构

健康检查请求流程：
HTTP Request → HealthEndpoint → CompositeHealth → HealthIndicator(s)↓
响应构建 ← 状态聚合 ← 组件检查 ← 详细信息收集

2.2 内置健康指示器详解

Spring Boot 提供了丰富的内置健康指示器：

健康指示器	检查内容	配置属性
DataSourceHealthIndicator	数据库连接和查询	spring.datasource.*
RedisHealthIndicator	Redis 连接和 ping	spring.redis.*
MongoHealthIndicator	MongoDB 连接和统计	spring.data.mongodb.*
DiskSpaceHealthIndicator	磁盘空间和阈值	management.health.diskspace.*
ElasticsearchHealthIndicator	ES 集群健康状态	spring.elasticsearch.*
RabbitHealthIndicator	RabbitMQ 连接和状态	spring.rabbitmq.*
CassandraHealthIndicator	Cassandra 连接和查询	spring.data.cassandra.*

2.3 自定义健康指示器深度实现

复杂数据库健康检查：

@Component
@Slf4j
public class ComprehensiveDatabaseHealthIndicator implements HealthIndicator {private final DataSource dataSource;private final JdbcTemplate jdbcTemplate;private final ObjectMapper objectMapper;// 健康检查配置@Value("${app.health.database.timeout:5}")private int queryTimeoutSeconds;@Value("${app.health.database.connection-pool-threshold:0.8}")private double connectionPoolThreshold;public ComprehensiveDatabaseHealthIndicator(DataSource dataSource, ObjectMapper objectMapper) {this.dataSource = dataSource;this.jdbcTemplate = new JdbcTemplate(dataSource);this.objectMapper = objectMapper;this.jdbcTemplate.setQueryTimeout(queryTimeoutSeconds);}@Overridepublic Health health() {Map<String, Object> healthDetails = new LinkedHashMap<>();List<String> errors = new ArrayList<>();try {// 1. 基础连接测试testBasicConnection(healthDetails, errors);// 2. 关键业务表检查checkCriticalTables(healthDetails, errors);// 3. 数据库性能指标collectPerformanceMetrics(healthDetails, errors);// 4. 连接池状态检查checkConnectionPool(healthDetails, errors);// 5. 数据库配置检查checkDatabaseConfiguration(healthDetails, errors);} catch (Exception e) {log.error("数据库健康检查异常", e);errors.add("健康检查执行失败: " + e.getMessage());}return buildHealthResponse(healthDetails, errors);}private void testBasicConnection(Map<String, Object> details, List<String> errors) {try {long startTime = System.currentTimeMillis();Integer result = jdbcTemplate.queryForObject("SELECT 1", Integer.class);long responseTime = System.currentTimeMillis() - startTime;details.put("basicConnection", Map.of("status", "UP","responseTimeMs", responseTime,"testResult", result));if (responseTime > 1000) {errors.add("数据库响应时间过长: " + responseTime + "ms");}} catch (Exception e) {details.put("basicConnection", Map.of("status", "DOWN"));errors.add("基础连接测试失败: " + e.getMessage());}}private void checkCriticalTables(Map<String, Object> details, List<String> errors) {List<String> criticalTables = Arrays.asList("users", "orders", "products");Map<String, Object> tableStatus = new HashMap<>();for (String table : criticalTables) {try {Long count = jdbcTemplate.queryForObject("SELECT COUNT(*) FROM " + table, Long.class);tableStatus.put(table, Map.of("exists", true,"recordCount", count));} catch (Exception e) {tableStatus.put(table, Map.of("exists", false));errors.add("关键表检查失败: " + table + " - " + e.getMessage());}}details.put("criticalTables", tableStatus);}private void collectPerformanceMetrics(Map<String, Object> details, List<String> errors) {try {// 获取数据库版本和状态String version = jdbcTemplate.queryForObject("SELECT VERSION()", String.class);// 获取活动连接数（MySQL示例）Integer activeConnections = jdbcTemplate.queryForObject("SELECT COUNT(*) FROM information_schema.PROCESSLIST", Integer.class);// 获取数据库大小（MySQL示例）Map<String, Object> dbSize = jdbcTemplate.queryForMap("SELECT table_schema as 'database', " +"ROUND(SUM(data_length + index_length) / 1024 / 1024, 2) as 'size_mb' " +"FROM information_schema.TABLES " +"GROUP BY table_schema");details.put("performance", Map.of("databaseVersion", version,"activeConnections", activeConnections,"databaseSize", dbSize));} catch (Exception e) {errors.add("性能指标收集失败: " + e.getMessage());}}private void checkConnectionPool(Map<String, Object> details, List<String> errors) {if (dataSource instanceof HikariDataSource) {HikariDataSource hikariDataSource = (HikariDataSource) dataSource;HikariPoolMXBean pool = hikariDataSource.getHikariPoolMXBean();int activeConnections = pool.getActiveConnections();int totalConnections = pool.getTotalConnections();int idleConnections = pool.getIdleConnections();double utilization = totalConnections > 0 ? (double) activeConnections / totalConnections : 0.0;details.put("connectionPool", Map.of("activeConnections", activeConnections,"idleConnections", idleConnections,"totalConnections", totalConnections,"utilization", String.format("%.2f%%", utilization * 100)));if (utilization > connectionPoolThreshold) {errors.add(String.format("数据库连接池使用率过高: %.2f%% (阈值: %.2f%%)", utilization * 100, connectionPoolThreshold * 100));}}}private void checkDatabaseConfiguration(Map<String, Object> details, List<String> errors) {try {// 检查数据库配置参数List<Map<String, Object>> dbConfig = jdbcTemplate.queryForList("SHOW VARIABLES WHERE Variable_name IN " +"('max_connections', 'innodb_buffer_pool_size', 'wait_timeout')");details.put("configuration", dbConfig);} catch (Exception e) {errors.add("数据库配置检查失败: " + e.getMessage());}}private Health buildHealthResponse(Map<String, Object> details, List<String> errors) {Health.Builder builder = Health.up();// 添加详细信息builder.withDetails(details);// 如果有错误，降级状态if (!errors.isEmpty()) {builder.withDetail("errors", errors);if (errors.stream().anyMatch(e -> e.contains("DOWN"))) {return builder.down().build();} else {return builder.status("DEGRADED").build();}}return builder.build();}
}

2.4 健康检查分组与聚合

management:endpoint:health:show-details: "when_authorized"show-components: "when_authorized"group:readiness:include: "db,redis,diskSpace,externalServices"show-details: "always"additional-path: "server:/health/readiness"liveness:include: "ping,memory"show-details: "never"additional-path: "server:/health/liveness"external:include: "paymentService,emailService,smsService"show-details: "when_authorized"

自定义健康检查组：

@Configuration
public class HealthGroupConfiguration {@Bean@ConditionalOnMissingBeanpublic HealthContributor externalServicesHealthGroup() {Map<String, HealthContributor> contributors = new HashMap<>();contributors.put("payment", paymentServiceHealthIndicator());contributors.put("email", emailServiceHealthIndicator());contributors.put("sms", smsServiceHealthIndicator());return new CompositeHealthContributor(contributors);}@Beanpublic PaymentServiceHealthIndicator paymentServiceHealthIndicator() {return new PaymentServiceHealthIndicator();}// 其他健康指示器...
}