[feature request] Add support for the unpack_json pipe

[arseny-zinchenko]

Would be great to be able to use some LogsQL pipes && functions.

Particularly, we needed for the unpack_json.

Can this be added?

So it may look like UNPACK_JSON(_msg):

SELECT
  _time AS "Timestamp",
  UNPACK_JSON(_msg) AS unpacked,
  unpacked.user_id,
  unpacked.status
FROM logs
WHERE component = 'backend'
  AND _msg = 'e51f6cf4-b50e-498b-b580-3ad3259425db'
ORDER BY _time DESC
LIMIT 100

[Amper]

Hey @arseny-zinchenko.

I'm not sure regarding your suggestion, because i don't want to invent some new SQL dialect with new syntax constructions - I would like to stay within the ANSI SQL syntax as much as possible.

At the moment, I have implemented the ANSI SQL JSON_VALUE function that use limited version of JSONPATH for extracting values from JSON. Here is the example:

SELECT
  JSON_VALUE(_msg, '$.user_id'),
  JSON_VALUE(_msg, '$.status'),
  JSON_VALUE(_msg, '$.some.nested.field.value') 
FROM logs
LIMIT 100

Let me know if this functionality is not enough for your scenarios.

Please also note that this feature does not support arrays, as LogsQL itself does not currently support them.

This functionality is released in v0.5.0.

[arseny-zinchenko]

Hi, @Amper

would like to stay within the ANSI SQL syntax

And that's great :-)

Keeping standards is always welcome.

Thanks for adding the JSON_VALUE, will try it later, but I guess this will be enough for our use cases.