StackOverflowError on jsonEncode of dict containing Dataset

Ignition
1

I need to persist some objects into my database and the quickest way seemed to be to convert them to JSON, then save that. That works ok with a Dataset, but fails on an object that contains a Dataset.

d = system.dataset.toDataset(["foo"], [[1]])
print system.util.jsonEncode(d)
# {"columns":[{"name":"foo","type":"java.lang.Integer"}],"rows":[[1]]}

d2 = {"myDataset": d}
print system.util.jsonEncode(d2)
# RuntimeError: maximum recursion depth exceeded (Java StackOverflowError)

d3 = {"myDataset": system.dataset.toPyDataSet(d)}
print system.util.jsonEncode(d3)
# RuntimeError: maximum recursion depth exceeded (Java StackOverflowError)

Python's json.dumps also fails, even on the basic Dataset. Java's jackson returns a similar error to jsonEncode.

I'm surprised I couldn't find anything else on the forum about this. Does anyone have a workaround, or do I have to convert all the Datasets to Python dicts/lists myself first?

2

Relevant thread. Looks like encoding the dataset first may work.

3

I can’t remember when it changed but a Dataset is now also interchangeable with a pyDataset.
Encode the dataset then add it to the dict as json, then it should work.
I believe the conversion may not work correctly unless it can detect the Dataset type directly.

4

That happened when the version 8.1.x jumped to 8.3.x.

If on 8.3 and below, this does not apply.

Link to change