My logs contain arbitrary array elements e.g. item=value0, item=value1.
The number of elements can vary from logline to logline.
I'm looking for a way to parse those elements and combine them into an array, e.g. items=[value0, value1] or join them into a string, but I haven't found any filter so far that appears to cover this use case.
Use a kv filter to parse the key=value pairs in the string into fields. Then write a piece of Ruby code in a ruby filter that processes the resulting fields and gathers the values of the fields whose names have the form order_items[ids][n].