External task client - multi instance collection

Camunda 7 Topics Discussion & Questions
1

What is the best way of passing collection for multi instance sub-process when using external task approach?
Providing simple ArrayList collection raises an engine error

Cannot locate class ‘SomeObject’

which is fine cause engine shouldn’t know about serialized class. I read that you suggest using json in such cases. I try serialize my collection (over 1000 items) into String using ObjectMapper class but this exceeds maximum size of column used to store process variables

Value too long for column "TEXT_ VARCHAR(4000)

How can I proceed this?

2

I have used Json array. Pass your list in as a stringified Json array and do type “Json” (case sensitive)

Then use SPIN to access the variable in the multi instance: myJson.elements() which will give you the collection needed for the multi instance

3

Thanks for guideline!
I works for me now :slight_smile:

4