How to put string concatenation inside the JSON Generator snap body?

Hi Guys ,

My scenario is following : I need to pass the whole Json inside the JSON generator snap .I have checked the velocity documnets that concate works by just appending ,like $a$b will concate the content of $a and $b . But in this case it is not working .

Json_input.zip (383 Bytes)

Here the “_” are for pipeline parameters and $ is for the variables coming from previous mapper .

Please help regarding this .

Capture

Hi,

To read the value from incoming mapper you just need to use <fieldname> and read from parameter you need to use {_parameterName}.

[
    {
        "readFromUpStreamMapper": $a,
        "readFromPrameter" : ${_parameterB}
    }
]

yes @gowdhaman008 I know these things .I have tried in that way also . Same error is coming .

I have tried with this :

"{

"remove": {
  "index": $CURRENT_IDX,
  "alias": ${_IDX_ALIAS}$Suffix_batch
  }

}"

My main issues is for the concatenate part . That is giving the trouble .

The following is working just fine :slight_smile:

"{

"remove": {
  "index": $CURRENT_IDX,
  "alias": ${_IDX_ALIAS}
  }

}"

@Rudradip, I think the issue is concatenating a pipeline variable and a regular variable which causes the syntax error. If you concatenate two regular variables it works fine. For example: $CURRENT_IDX$SUFFIX_BATCH

If you concatenate two pipeline variables, it will cause the syntax error:
_IDX_ALIAS_IDX_ALIAS

or even with a different syntax: {_IDX_ALIAS}{_IDX_ALIAS} will cause the syntax error

I am copying @tstack and @cjhoward18 to comment on this as they may be able to share better insights into this.