5

Is it possible to use xmlHttpRequest in NIFI processor to invoke remote rest service? In my case the ExecuteScript processor (using Javascript) can't evaluate XMLHttpRequest; is there any similar solution I can use to get response data?

var OutputStreamCallback = Java.type("org.apache.nifi.processor.io.OutputStreamCallback");
var StandardCharsets = Java.type("java.nio.charset.StandardCharsets");

Date.prototype.isValid = function () {
    return (Object.prototype.toString.call(this) === "[object Date]")
        && !isNaN(this.getTime());
};

var flowFile = session.get();

if (flowFile != null) {
    var fromDate = flowFile.getAttribute('fromDate')
    var uid = flowFile.getAttribute('uid')

    var xmlhttp = null;
    var result = null;

        xmlhttp = new XMLHttpRequest();
        if (typeof xmlhttp.overrideMimeType != 'undefined') {
            xmlhttp.overrideMimeType('application/json');

    } else if (window.ActiveXObject) {
        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    xmlhttp.open('GET', "similar url here WorkInfo?dateFrom=?&uid=?", true);
    xmlhttp.send(dateFrom, uid);
    if (xmlhttp.status == 200) {
        result = 'WorkInfoDate'
    }
    flowFile = session.putAttribute(flowFile, 'filename', fromDate + '_' + result);

    flowFile = session.write(flowFile,
        new OutputStreamCallback(function (outputStream) {
            outputStream.write(command.getBytes(StandardCharsets.UTF_8))
        }));

    session.transfer(flowFile, REL_SUCCESS)
}
Andy
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Sagitarius
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1 Answers1

3

There is an InvokeHttp processor that can be used to invoke a REST service without writing any code:

https://nifi.apache.org/docs/nifi-docs/components/org.apache.nifi/nifi-standard-nar/1.3.0/org.apache.nifi.processors.standard.InvokeHTTP/index.html

The response from the service will be written to the contents of the flow file.

Bryan Bende
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    I have thought about this nifi-processor but in this case i can'r imagine how can i pass and change parameters(which are essential for get method) in my case they change in every minute – Sagitarius Aug 08 '17 at 13:15
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    The URL property supports expression language so you can have a url like: http://someservice?param1=${v1}&param2=${v2} and then you can set v1 and v2 as attributes before this processor using UpdateAttribute. – Bryan Bende Aug 08 '17 at 14:49