Spring Cloud结合AWS Lambda时@ExceptionHandler失效问题求助

问题根源 #

Spring Cloud Lambda处理API Gateway Http Api触发器时，请求流转未经过完整的Spring Web MVC Servlet栈，导致常规@ControllerAdvice/@ResponseStatus的异常处理逻辑无法直接生效。

可行解决方案 #

1. 适配Lambda的全局异常处理器

使用@RestControllerAdvice并实现Lambda专用的ErrorResponseExceptionHandler，确保异常响应符合API Gateway Http Api的格式：

import org.springframework.cloud.function.adapter.servlet.ErrorResponseExceptionHandler;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

@RestControllerAdvice
public class GlobalLambdaExceptionHandler implements ErrorResponseExceptionHandler {

    @ExceptionHandler(TestException.class)
    public ResponseEntity<ErrorPayload> handleTestException(TestException ex) {
        ErrorPayload error = new ErrorPayload(HttpStatus.BAD_REQUEST.value(), ex.getMessage());
        return ResponseEntity
                .status(HttpStatus.BAD_REQUEST)
                .contentType(MediaType.APPLICATION_JSON)
                .body(error);
    }

    // 定义标准错误响应体
    public static class ErrorPayload {
        private int statusCode;
        private String message;

        public ErrorPayload(int statusCode, String message) {
            this.statusCode = statusCode;
            this.message = message;
        }

        // Getters（序列化需要）
        public int getStatusCode() { return statusCode; }
        public String getMessage() { return message; }
    }
}

2. 在Lambda Handler中手动捕获异常

如果全局处理仍不生效，直接在自定义Handler层捕获并构造响应：

import com.amazonaws.services.lambda.runtime.Context;
import org.springframework.cloud.function.adapter.aws.SpringBootRequestHandler;
import org.springframework.http.HttpStatus;

public class TestLambdaHandler extends SpringBootRequestHandler<APIGatewayHttpApiV2Request, APIGatewayHttpApiV2Response> {

    @Override
    public APIGatewayHttpApiV2Response handleRequest(APIGatewayHttpApiV2Request input, Context context) {
        try {
            return super.handleRequest(input, context);
        } catch (TestException ex) {
            return APIGatewayHttpApiV2Response.builder()
                    .statusCode(HttpStatus.BAD_REQUEST.value())
                    .body("{\"statusCode\":400,\"message\":\"" + ex.getMessage() + "\"}")
                    .isBase64Encoded(false)
                    .build();
        }
    }
}

3. 通过配置映射异常到状态码

在application.properties中添加异常与HTTP状态码的映射，同时确保TestException是运行时异常：

# 格式：spring.cloud.function.adapter.aws.error.mapping.全限定异常类名=状态码
spring.cloud.function.adapter.aws.error.mapping.com.yourpackage.TestException=400

异常类定义：

public class TestException extends RuntimeException {
    public TestException(String message) {
        super(message);
    }
}

关键检查项 #

• 确保Lambda Handler继承SpringBootRequestHandler，而非普通RequestHandler，否则Spring上下文无法加载异常处理器。
• 确认使用APIGatewayHttpApiV2Request/APIGatewayHttpApiV2Response（对应Http Api），不要混用旧版APIGatewayProxyRequestEvent（对应REST Api）。
• 依赖检查：必须引入spring-cloud-function-adapter-aws，若使用Web注解需引入spring-boot-starter-web并排除嵌入式Tomcat：

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-function-adapter-aws</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
        <exclusions>
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-tomcat</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
</dependencies>

内容的提问来源于stack exchange，提问作者Thiago