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apache-nifi

update string value, using file content

The incoming csv-file has the following schema:

 latitude;longtitude
 90.232;24.244

I need to generate flow file, by updating incoming schema with new field "json".

Expected outcoming schema is:

latitude;longtitude;json
90.232;24.244;"{\"type\":\"Point\",\"coordinates\":[90.232,24.244]}"

So I need to extract latitude and longtitude values and put them into json (represented as string value).

For this aim I used UpdateRecord with Properties:

UpdateRecord

/json value is:

  {"type":"Point","coordinates":[${\latitude},${\longtitude}]}

Also I tried:

 {"type":"Point","coordinates":[${latitude},${longtitude}]}

But the output is:

 latitude;longtitude;json
 90.232;24.244;"{\"type\":\"Point\",\"coordinates\":[,]}"

So nothing is put to coordinates "placeholders".

Can anybody help me?

Solution

  • Use a QueryRecord:

    • CSVReader (separator: ;)
    • CSVRecordSetWriter (separator: ;)
    • add-field (dynamic property):
    SELECT latitude, longtitude, 
'{"type":"Point","coordinates":[' || latitude || ',' || longtitude || ']}' AS json 
FROM FLOWFILE

    input

    latitude;longtitude
90.232;24.244

    output

    latitude;longtitude;json
90.232;24.244;"{\"type\":\"Point\",\"coordinates\":[90.232,24.244]}"