Re: [Jsonpath] JSONPath or JMESPath

[Davide Bettio <[e-mail]>]

Hello,

On  20200811, at 18:30, Carsten Bormann <[e-mail]> wrote:
> Sure.  So what are the advantages of JMESPath over JSONPath that are not about what we’ve set out to do here?

The main  difference I found so far is that JMESPath supports
functions, which is IMHO an useful feature, however there are 2 major
drawbacks:
- Increased implementation complexity compared to JSONPath (my Elixir
JSONPath implementation counts a few hundred lines of code).
- JMESPath expressions might be computational heavier, since it has
support for functions such as sort, avg, map, etc... that might be
expensive on huge datasets.

In my opinion the right balance between powerfulness and enabling
simple implementations has been so far one of the key factors that
made JSONPath popular over other alternatives, even if it lacks
support for aggregation functions.

I also realize that exists a kind of hierarchy between existing
competing solutions, and each one has valid use cases:
JSONPointer: no computation (hence deterministic processing time),
returns just a subtree
JSONPath: allows filtering and projections, however the result is
still a subset of the original dataset
JMESPath: allows computations (some of them expensive), and the output
value might not exist in the original JSON object

At the moment JSONPointer and JMESPath have complete specs, while
JSONPath doesn't.

Regards,
Davide Bettio.