Re: [Boston.pm] perl data to/from JSON?

Scanning projects on my drive, i see lots of plain "use JSON;",  some "use
JSON qw(encode_json decode_json);", a couple "use JSON::PP;" and one client
using "JSON::XS", which would be desirable for speed (e.g. scaling web
servirces).  I don't have any examples of  JSON::Tiny.

On MetaCpan, plain "JSON" has lots of reverse dependencies and is
up-to-date.
Tiny has many fewer rev-deps (packages that require it).

Plain "JSON" uses "JSON::XS" when available and falls back to JSON::PP ...
and carries its own JSON::backportPP along as final default.
So if you "use JSON;" you can install XS version later for speed with no
change to using code.

As to Compatibility ... one can hope but no guarantees. EcmsScript is the
standardized version of JavaScript, but the implementations aren't ES\d+
they're something else.  The important thing is for your group to define
what structure you're passing and write test cases to verify that your
script reads and writes that format. And they do likewise.





On Fri, Jan 25, 2019 at 4:08 PM Greg London <email-2Ro/Dj86MvDSUeElwK9/[email protected]> wrote:

> This is a work-related issue, so certain decisions are out of my control.
> Also, I know only rudimentary python, and I know absolutely nothing about
> JSON, so, this whole thing may be complete garbage for reasons I'm unaware
> of. That said:
>
> We have a number of perl and python scripts and we are looking to share
> data between them. It was decided that we use a JSON file format to store
> data and then have all the scripts read/write this format so it wouldn't
> matter if the script was python or perl.
>
> basically I want to do this:
>
> my $my_complex_data = [ {key1=>data1,key2=>data2}, [ {}, {key=>[] } ]];
> use Storable qw(nstore dclone retrieve);
> nstore ($my_complex_data, 'filename');
> my $revived = retrieve('filename');
>
> But have the intermediate file format be JSON instead of Storable's format.
>
> We also have to go through a process to get executable modules installed,
> so if it can be pure perl, I can just copy the file to a local directory,
> check it into the project, and use it without delay.
> I can get executables installed, but they have to be approved through a
> process, and then someone has to make sure they're installed on every
> machine everywhere, including all teh machines on LSF. so executables are
> possible, but likely a bit more painful.
>
> I looked for JSON on CPAN and found... hundreds of matches???
>
> It looks like JSON::PP is pure perl and does what I want.
> https://metacpan.org/pod/JSON::PP
> however, it says:
> "JSON::PP is a pure perl JSON decoder/encoder, and (almost) compatible to
> much faster JSON::XS"
>
> How compatible is "almost" compatible?
>
> I'm not actually worried about being compatible with JSON::XS. I'm worried
> about being compatible with whatever JSON file some python script ends up
> generating, or generating a JSON file that a python script may have to
> read.
>
>
> JSON::XS https://metacpan.org/pod/JSON::XS says:
> "This module converts Perl data structures to JSON and vice versa. Its
> primary goal is to be correct"
>
> How "incorrect" might JSON::PP be?
>
> JSON::PP says it is not "java script friendly" and that "If you need
> JavaScript-friendly RFC7159-compliant pure perl module, try JSON::Tiny,"
>
> https://metacpan.org/pod/JSON::Tiny
>
> JSON::Tiny says "it is among the fastest pure-Perl implementations of RFC
> 7159." But it doesn't say anything about "correct"ness.
>
> So, what's the point of JSON::PP if JSON::Tiny does everything better and
> is also pure perl?
>
> Has anyone used any of these modules?
>
> If I wanted to take a complex perl data structure, save it to JSON format,
> and then have a python script read that JSON file, possibly modify the
> structure, and save it back as JSON, and then my perl script open that
> JSON back up, and read it back in again, which module is most likely to be
> cross-language compatible?
>
> Any help woudl be appreciated.
> Greg
>
> _______________________________________________
> Boston-pm mailing list
> [email protected]
> https://mail.pm.org/mailman/listinfo/boston-pm
>


-- 
Bill Ricker
[email protected]
https://www.linkedin.com/in/n1vux