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rpatrick00's avatar
rpatrick00
Contributor
5 years ago
Solved

Mapping fields from objects in an array to fields in objects in an array

So I have an input schema that has a structure similar to the one shown here:

{
    "MatchUpdatePartyPayload:" {
        "Address": [
            {
                "NonStandardUS": {
                    "Line1": <String>,
                    "Line2": <String>,
                    "Line3": <String>,
                    "City": <String>,
                    "State": <String>,
                    "Zip": <String>
                },
                "Foreign": {
                    "Line1": <String>,
                    "Line2": <String>,
                    "Line3": <String>,
                    "Line4": <String>,
                }
            }
        ]
    }
}

I need to map these address fields to an output structure that is similar, but not quite the same. I have tried using the Mapper to do this and it is creating mapping table entries that look like this:

Expression => jsonPath($, "$MatchUpdatePartyPayload.Address[*].NonStandardUS.Line1")
Target Path => jsonPath($, "$MatchUpdateParty.Address[*].NonStandardUS.AddressLine1")

The input documents to the mapper all haver Line1 as a String. Unfortunately, the Mapper output all have AddressLine1 as an array of strings–which is not what I need. What do I need to do to fix the mapping to assign input String fields to output String fields for each element in the array?

14 Replies

    • rpatrick00's avatar
      rpatrick00
      Contributor

      Thanks for the reply. This is going to be painful since some of our payloads have a dozen or more optional fields that are arrays…

  • @skatpally I am not sure how this sample would work. In my case, most arrays have 1 to unbounded elements. The Group By N is asking for the number of elements to put back into the array that was split. Since each document will have different numbers of array elements, I don’t see how your approach can work. What am I missing?

    Here is the start of a sample pipeline just to handle a single mapping. Mapping Conundrum_2020_09_28.slp (29.7 KB)

    • skatpally's avatar
      skatpally
      Former Employee

      A value of 0 instructs the Snap to group all input documents into a single document.

  • @skatpally, is that all in the “pipeline’s current document” or all (meaning across all documents)? In my sample, I have 5 separate documents in the JsonGenerator. Will 0 cause it to put the values of all 5 documents in it or only the ones from the currently processing document?

    • skatpally's avatar
      skatpally
      Former Employee

      It will group all the incoming docs.

      For your scenario, you need to use a unique ID and do a split and work on the transformations and use a Group by field snap to merge the data back. Attaching the sample to get an idea. Mapping Conundrum_2020_09_29 (1).slp (16.9 KB)

  • @rpatrick00 if it’s one to one try this in mapper - jsonPath($, “$MatchUpdatePartyPayload.Address[*].NonStandardUS.Line1”).toString() also make sure check null safe option in mapper.

  • @skatpally Your join is not working properly even with only two of the 5 streams. Notice on the third document that the MatchUpdateParty element only contains the Address field and the Name field is stashed in the input1_MatchUpdateParty element. So now I have an array mapping problem all over again? ☹️

  • Yeah, I finally realized that Join snap cannot handle joining fields into same top-level structure so I eliminated the top level structure for the join, and then used a mapper to add the top-level structure back. I had to write a custom snap (not included) to prune off all the null fields/elements created by the Null Safe Access mappers…

    I must say that was a lot more painful than I think it should be. If I were to use this in an actual business process, the logic of the business process flow would get lost due to this complex mapping flow…

    Here is the final working example (with all of the nulls still present).

    Mapping Conundrum_2020_09_30 (3).slp (56.6 KB)

    Thanks for the help,
    Robert