JSON.OBJLEN key [path]
Available in: Redis Stack
Time complexity: O(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
Reports the number of keys in the JSON Object at path in key.
path defaults to root if not provided. Returns null if the key or path do not exist.
Return
[] if the matching JSON value is not an object.
Examples
redis> JSON.SET doc $ '{"a":[3], "nested": {"a": {"b":2, "c": 1}}}'
OK
redis> JSON.OBJLEN doc $..a
1) (nil)
2) (integer) 2