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problem while using RouteOnAttribute (cannot read json attribute and always sends flow to unmatch)

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while using RouteOnAttribute nifi processor , i have input of json data

[{"dev":"xyz","detail":"abc"}] which i got from convertRecord processor

Routing Strategy :Route to Property name

ifmatch: ${dev:equals( "xyz" )}

I tried ${dev:matches( "xyz")} in both single quotes and double quotes still am not getting flowfile redirecting towards "ifmatch" . its redirecting to unmatched

is there anyway to resolve this i tried many other option

The flowfile content is different from attributes . Content is arbitrary -- could be empty, text, KB of XML, GB of video or binary. Each flowfile also has attributes which are key/value pairs of String s kept in memory.

If you want to route on this piece of data, you have multiple options:

Use


    RouteOnText


    RouteOnContent

to use the actual flowfile content directly.

Extract it to an attribute using


    EvaluateJsonPath

and then route on that attribute.

The Apache NiFi User Guide and In-Depth provide more information around this distinction.

Am using EvaluateJsonPath and below is my configuration Destination:flowfile-attribute Return Type: auto-detect Path Not Found Behavior: warn Null Value Representation :empty string Device : $.dev i am getting Device as empty string when i check in flowfile attributes is their any particular reason – Manmit Aug 14, 2020 at 8:44 Your content is an array of JSON objects, not a single one, so you'll need something like


    $[0].dev

to extract the

dev

key/value pair from the first (zero-indexed) element of the array. – Andy Aug 18, 2020 at 23:48

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