serverlessExample-lambda-listCharacters.js

serverlessExample-lambda-listCharacters.js

'use strict';
const AWS = require('aws-sdk');
const dynamoClient = new AWS.DynamoDB.DocumentClient({
    region: 'us-east-1'
});

function buildResponse(dynamoData) {
    console.log("dynamoData: " + JSON.stringify(dynamoData));
    return dynamoData;
}

function responseHandler(statusCode, responsePayload, callback) {
    const response = {
        statusCode: 200,
        headers: {
            "Access-Control-Allow-Origin": "*", // Required for CORS support to work
            "Access-Control-Allow-Credentials": true // Required for cookies, authorization headers with HTTPS
        },
        body: JSON.stringify(responsePayload)
    };

    console.log("responseHandler: " + JSON.stringify(response));
    callback(null, response);
}

function buildQueryParams(classFilter, resultLimit, scanIndexForwardValue) {
    var gameId = "1";
    var queryParams = {
        TableName: "characterData",
        Limit: resultLimit,
        ScanIndexForward: scanIndexForwardValue,
        KeyConditionExpression: "#gameId = :gameId",
        ExpressionAttributeNames: {
            "#gameId": "gameId"
        },
        ExpressionAttributeValues: {
            ":gameId": gameId
        }
    }
    console.log("buildQueryParams \n\n " + JSON.stringify(queryParams) + " \n\n");
    return queryParams;
}

exports.handler = function(event, context, callback) {
    console.log('Received event:', JSON.stringify(event, null, 2));

    try {
        // our HTTP query parameters
        var sortField = event.queryStringParameters.sortfield;
        var sortOrder = event.queryStringParameters.sortorder;
        var classFilter = event.queryStringParameters.classfilter;
        var resultLimit = event.queryStringParameters.resultLimit;

        console.log("API Params: \
        sortField: " + sortField + "\
        sortOrder: " + sortOrder + "\
        classFilter: " + classFilter + "\
      ");

        // sort order
        var scanIndexForwardValue = true;

        if (sortOrder == "desc") {
            scanIndexForwardValue = false;
        }

        var queryString = buildQueryParams(classFilter, resultLimit, scanIndexForwardValue);
        // Get response
        dynamoClient.query(queryString, function(err, itemData) {
            if (err) {
                responseHandler(500, err, callback);
            } else {
                responseHandler(200, buildResponse(itemData), callback);
            }
        });
    } catch (ex) {
        console.log("Error -- exports.handler: " + ex);
        responseHandler(500, ex, callback);
    }
}