Support JsonPath functions in JsonPath expressions

[FrankChen021]

Fixes #11291

Description

This PR allows users to use JsonPath functions in JsonPath expressions during ingestion. Currently, JsonPath is used to extract values inside a JSON object. However, JsonPath supports a bunch of function expressions which are not supported by Druid now. For example, '$.property_name.length()' can be used to get the length of a Json array object 'property_name'. This function would be useful in some cases.

The reason why Druid does not support JsonPath functions is very simple, the original code assumes that the JsonPath expressions would return a Json object. However, if a JsonPath function is applied, the return type is the raw object instead of Json object.

So fixing the bug of 'length()' function also brings support to other functions. I also brings the support of these functions to orc/avro/parquet data format.
Following matrix shows the current supported JsonPath functions and corresponding data formats.

Function	Description	Output type	json	orc	avro	parquet
min()	Provides the min value of an array of numbers	Double	✓	✓	✓	✓
max()	Provides the max value of an array of numbers	Double	✓	✓	✓	✓
avg()	Provides the average value of an array of numbers	Double	✓	✓	✓	✓
stddev()	Provides the standard deviation value of an array of numbers	Double	✓	✓	✓	✓
length()	Provides the length of an array	Integer	✓	✓	✓	✓
sum()	Provides the sum value of an array of numbers	Double	✓	✓	✓	✓
concat(X)	Provides a concatenated version of the path output with a new item	like input	✓	✗	✗	✗
append(X)	add an item to the json path output array	like input	✓	✗	✗	✗
keys()	Provides the property keys (An alternative for terminal tilde ~)	Set	✗	✗	✗	✗

• append, concat are not fully supported, because I don't see there's strong need to use them.
• keys() is not supported because it's not supported by current JsonPath library used by Druid. And also I don't see there's a strong need to use this JsonPath function.

---

This PR has:

• been self-reviewed.
  • using the concurrency checklist (Remove this item if the PR doesn't have any relation to concurrency.)
• added documentation for new or modified features or behaviors.
• added Javadocs for most classes and all non-trivial methods. Linked related entities via Javadoc links.
• added or updated version, license, or notice information in licenses.yaml
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
• added integration tests.
• been tested in a test Druid cluster.

[FrankChen021]

CI failes when testing ORC extension which might has something to do with this PR. I will check it.

[FrankChen021]

Marked as WIP because a change to a binary ORC message file was lost. I have to re-do the change.

[dkoepke]

Hi, @FrankChen021, we've run into this issue, and I was wondering if we can help get this PR over the finish line. Do you think you'd have the time to update the PR for the lost change to the ORC file? If not, we can take a look.

At a quick glance, it seems like the failing assertion is:

Assert.assertEquals("2", Iterables.getOnlyElement(row.getDimension("struct_list_struct_intlistLength")));

I'm wondering if this is a spurious check, and the assertion for struct_list_struct_middleListLength just below it is the intended check. I don't see a JSON path spec that'd produce the struct_list_struct_intlistLength in the row, but I'm definitely missing some context here.

[FrankChen021]

@dkoepke There must be some reasons that I added a new field to the ORC example file and that check. But I can't remember now. I will take a look in this weekend.

[zachjsh]

Thanks @FrankChen021 !

[FrankChen021]

@zachjsh @jon-wei Thanks for your review.