com.iluwatar.serverless.baas.api.AbstractDynamoDbHandler.java Source code

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Here is the source code for com.iluwatar.serverless.baas.api.AbstractDynamoDbHandler.java

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/**
 * The MIT License
 * Copyright (c) 2014 Ilkka Seppl
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.iluwatar.serverless.baas.api;

import com.amazonaws.regions.Regions;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper;
import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

/**
 * abstract dynamodb handler
 * @param <T> - serializable collection
 */
public abstract class AbstractDynamoDbHandler<T extends Serializable> {
    private DynamoDBMapper dynamoDbMapper;

    private ObjectMapper objectMapper;

    public AbstractDynamoDbHandler() {
        this.initAmazonDynamoDb();
        this.objectMapper = new ObjectMapper();
    }

    private void initAmazonDynamoDb() {
        AmazonDynamoDB amazonDynamoDb = AmazonDynamoDBClientBuilder.standard().withRegion(Regions.US_EAST_1)
                .build();

        this.dynamoDbMapper = new DynamoDBMapper(amazonDynamoDb);
    }

    protected DynamoDBMapper getDynamoDbMapper() {
        return this.dynamoDbMapper;
    }

    protected ObjectMapper getObjectMapper() {
        return objectMapper;
    }

    public void setDynamoDbMapper(DynamoDBMapper dynamoDbMapper) {
        this.dynamoDbMapper = dynamoDbMapper;
    }

    protected Map<String, String> headers() {
        Map<String, String> headers = new HashMap<>();
        headers.put("Content-Type", "application/json");

        return headers;
    }

    /**
     * API Gateway response
     *
     * @param statusCode - status code
     * @param body - Object body
     * @return - api gateway proxy response
     */
    protected APIGatewayProxyResponseEvent apiGatewayProxyResponseEvent(Integer statusCode, T body) {
        APIGatewayProxyResponseEvent apiGatewayProxyResponseEvent = new APIGatewayProxyResponseEvent()
                .withHeaders(headers());
        try {
            apiGatewayProxyResponseEvent.withStatusCode(statusCode)
                    .withBody(getObjectMapper().writeValueAsString(body));

        } catch (JsonProcessingException jsonProcessingException) {
            throw new RuntimeException(jsonProcessingException);
        }

        return apiGatewayProxyResponseEvent;
    }
}