CloudSearchドメインのデータをエクスポートする

var AWS = require('aws-sdk');
var fs = require('fs');

AWS.config.update({
        accessKeyId: '*****************',
        secretAccessKey: '*********************************',
        region: 'ap-northeast-1',
        endpoint: 'search-hogehoge-fdsfajfpfaihfaophsdfpafd.ap-northeast-1.cloudsearch.amazonaws.com'
});

var batchSize = 10000;  // 一度に取得するドキュメント数
var maxBatchCount = 5;  // 取得回数

var compteur = 0;
var result = [];
var resultMessage = [];

var params = {query:""};
var cloudsearchdomain = new AWS.CloudSearchDomain(params);

function launchSearch(theContext) {
    process.stdout.write('Launch AWS.CloudSearch ');

    if (theContext==null) {
        process.stdout.write('initial request ... ');
    } else {
        var current  = (theContext.start/batchSize) +2 ;
        var totalRun = (Math.ceil(theContext.found/batchSize  * 10) / 10) + 1;
        process.stdout.write('( ' + current + ' / ' + totalRun + ' )       ... ');
    }

    // https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/CloudSearchDomain.html#search-property
    params = {
        query:"matchall",
        cursor: (theContext==null)?"initial":theContext.cursor,
        size:batchSize,
        queryParser: "structured",
        return: "_all_fields"
    };

    var forCursor = new AWS.CloudSearchDomain(params);

    forCursor.search(params, function(err, data) {
        if (err) {
            console.log("Failed with params :" );
            console.log(err);
        } else {
            resultMessage = data;
            compteur = compteur + data.hits.hit.length;
            for(var i=0;i<data.hits.hit.length;i++){
                result.push(data.hits.hit[i]);
            };
        }

        process.stdout.write(resultMessage.hits.hit.length + ' hits found.');

        if (resultMessage.hits.hit.length==0 | maxBatchCount <= current) {
            process.stdout.write(' Done.\n\nLet\'s create thte file...\n');
            writeTheFile(result);
        } else {
            process.stdout.write('\n');
            var myContext = {};
            myContext.cursor = resultMessage.hits.cursor;
            myContext.start = resultMessage.hits.start;
            myContext.found = resultMessage.hits.found;
            myContext.retrived = resultMessage.hits.hit.length;
            launchSearch(myContext);
        }
    });
}

function writeTheFile(myResult) {
    fs.writeFile(process.argv[2], JSON.stringify(myResult), function(err) {
        if(err) {
            return console.log(err);
        }
    });
    process.stdout.write("DONE : File '"+ process.argv[2] + "' generated  ( " + compteur + " elements ).\n");
}

/*Check parameters*/
if (!process.argv[2]) {
     //console.log(process.argv);
    process.stdout.write('ERROR : the output filename is expected as argumment.\n');
    process.exit();
 } else {
    launchSearch();
}