Hello,
Regarding the CsvToJson template, here is what is happening...
1) GenerateFlowFile produces a FlowFile to simulate some data
2) ReplaceText sets the content of that flow file to "a,b,c,d" to represent
and example CSV line
Steps 1 and 2 are just simulating data that would really come from
somewhere else.
3) ExtractText applies a regular expression to the FlowFile to extract the
columns of the CSV...
In this case there is an attribute added to the processor called "csv" with
a value of (.+),(.+),(.+),(.+)
After the FlowFile passes through this processor it will have added
attributes:
csv.1 = a
csv.2 = b
csv.3 = c
csv.4 = d
4) ReplaceText uses those new attributes to build a new JSON document by
setting the replacement value to:
{
"field1" : "${csv.1}",
"field2" : "${csv.2}",
"field3" : "${csv.3}",
"field4" : "${csv.4}"
}
5) UpdateAttribute is not doing anything in this example, it is just a
place holder to send the results of step 4 somewhere and end the flow, you
would replace this with whatever you want to do with your JSON.
-Bryan
On Tue, May 3, 2016 at 4:26 AM, idioma <[email protected]> wrote:
> I am comment on my own question, just to clarify one aspect of the existing
> template. I am not sure why we need ExtractText between the first
> ReplaceText and the one that in the flow comes before UpdateAttribute? I am
> not sure I have fully understood the flow, what is the actual value for
> that
> step?
>
> Thank you so much for your help.
>
>
>
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