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javascriptnode.jsbufferaws-lambdaamazon-kinesis

In lambda using node.js how can I parse the data from a kinesis stream


I have the following lambda function set up with kinesis as its event source. The data is coming through as a stream, here I am parsing this to come through as a string e.g. {id=2, sourceIp=220.220.1.220 }. I want to convert this to an object in node.js. How can I do this?

exports.handler = (event, context) => {

    event.Records.forEach(function(record) {
        var data = new Buffer(record.kinesis.data, 'base64').toString('ascii');
        console.log('data: ', data)
    });
};

Solution

  • I'm not familiar with the actual output of Kinesis but I'm a bit confused by the example you've given. The test example test even in lambda shows the Kinesis object looking like this

    "kinesis": {
        "partitionKey": "partitionKey-3",
        "data": "SGVsbG8sIHRoaXMgaXMgYSB0ZXN0IDEyMy4=",
        "kinesisSchemaVersion": "1.0",
        "sequenceNumber": "49545115243490985018280067714973144582180062593244200961"
    }
    

    Which means the parsed string should look something like "id=2,sourceIp=220.220.1.220" from your example. If that is the case you could do something convoluted like this to get the data into a proper object.

    var json = {};
    data.split(',').map(function(each){
        return each.split('=');
    }).forEach(function(pair){
        json[pair[0]] = pair[1];
    });