在 Serverless Java 函数中获取 AWS Cognito 用户 ID

Question

我正在关注https://serverless-stack.com/ tutorial which uses the Serverless framework to create an API that inserts objects into a DynamoDB table and associates them to the authenticated AWS Cognito user. I am attempting to convert the Node.js code to Java but I have hit a problem when getting the Cognito identity as shown on this page

userId: event.requestContext.identity.cognitoIdentityId,

我预计以下 Java 代码行是等效的：

final CognitoIdentity identity = context.getIdentity();
final String userId = identity.getIdentityId();

但是 userId 是空的。

我正在使用 aws-api-gateway-cli-test 实用程序使用 Cognito 用户的凭据调用我的 API，如 on this page 所示。身份验证通过，但处理程序中的 userId 为空。

这是我的功能：

package com.mealplanner.function;

import java.util.Map;

import com.amazonaws.services.lambda.runtime.CognitoIdentity;
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.mealplanner.dal.MealRepository;
import com.mealplanner.domain.Meal;
import com.serverless.ApiGatewayResponse;

public class CreateMealHandler implements RequestHandler<Map<String, Object>, ApiGatewayResponse> {

    @Override
    public ApiGatewayResponse handleRequest(final Map<String, Object> request, final Context context) {
        try {
            final CognitoIdentity identity = context.getIdentity();    
            final String userId = identity.getIdentityId();

            final JsonNode body = new ObjectMapper().readTree((String) request.get("body"));
            final MealRepository repository = new MealRepository();
            final Meal meal = new Meal();
            meal.setUserId(userId);
            meal.setDescription(body.get("description").asText());
            repository.save(meal);

            return ApiGatewayResponse.builder()
                    .setStatusCode(200)
                    .setObjectBody(meal)
                    .build();
        } catch (final Exception e) {
            final String errorText = String.format("Error saving meal with request [%s]", request);
            LOGGER.error(errorText, e);
            return ApiGatewayResponse.builder()
                    .setStatusCode(500)
                    .setObjectBody(errorText)
                    .build();
        }
    }
}

这是serverless.yml中的函数定义：

createMeal:
    handler: com.mealplanner.function.CreateMealHandler
    events:
      - http:
          path: /meals
          method: post
          cors: true
          authorizer: aws_iam

我是否遗漏了一些配置或者我没有正确翻译 Node.js 代码？

如果我遗漏了任何相关信息，可以在此处获得完整代码：https://github.com/stuartleylandcole/meal-planner/tree/add-users。我会用任何遗漏的内容更新这个问题，以确保所有相关信息都是独立的。

Answer 1

原来我没有正确翻译Node.js代码。要访问 CognitoIdentityId，我必须从 request 对象获取 requestContext，然后获取 identity 对象，如下所示：

public ApiGatewayResponse handleRequest(final Map<String, Object> request, final Context context) {
    final Map<String, Object> requestContext = (Map<String, Object>) request.get("requestContext");
    final Map<String, Object> identity = (Map<String, Object>) requestContext.get("identity");
    final String userId = (String) identity.get("cognitoIdentityId");

    // etc
}

在 Serverless Java 函数中获取 AWS Cognito 用户 ID

Get AWS Cognito user ID in Serverless Java function

java

aws-lambda

serverless-framework

serverless