On Sun, Aug 8, 2021 at 3:35 PM Diab Jerius <djer...@cpan.org> wrote: > Howdy! > > I've a module ( > https://metacpan.org/release/DJERIUS/Data-Record-Serialize-0.27-TRIAL) > which may use JSON and YAML writers. > > For JSON, I use JSON::MaybeXS. Cpanel::JSON::XS >= 3.0236 is required. > > My code can use either YAML::XS or YAML::PP. YAML::XS >= 0.67 is > required. > > Since JSON & YAML output are optional, I've encoded the XS dependencies as > runtime recommendations, rather than requirements. JSON::MaybeXS is > specified as a runtime dependency (as is YAML::PP, but that's a mistake; it > should also be a runtime recommendation). > > Here are the relevant bits of META.json ( > https://metacpan.org/release/DJERIUS/Data-Record-Serialize-0.27-TRIAL/source/META.json#L98 > ) > > "runtime" : { > "recommends" : { > "Cpanel::JSON::XS" : "3.0236", > "JSON::PP" : "0", > "YAML::XS" : "0.67" > }, > "requires" : { > "JSON::MaybeXS" : "0", > "YAML::PP" : "0", > } > }, > > Here's the problem, illustrated by this CPAN testers failure: > > http://www.cpantesters.org/cpan/report/2f961e48-6bf6-1014-90df-a468c69b7236 > > The smoker has versions of Cpanel::JSON::XS and YAML::XS which are older > than my required versions. Since the ::XS versions are prioritized over > the ::PP versions, the code uses those and thus fails the tests. I > presume that because the ::XS versions are recommendations rather than > requirements, they weren't updated to the versions that the code requires. > > Is there some way of triggering an update to the required versions via the > metadata, or should I put a runtime version check into the tests and skip > if the appropriate versions aren't installed? > > For production runs, I'll have to add a runtime check in the code which > falls back to YAML::PP if the version of YAML::XS is too old, but I don't > see how I can do that with JSON::MaybeXS, as there are no hooks to indicate > acceptable versions of the backend. I think my only option is to take the > same approach as for YAML, namely manually specifying which backend > libraries are acceptable. I don't like this, as now I can't automatically > take advantage of JSON::MaybeXS's list of backends. > > Any advice on how to gracefully handle this situation? >
There's only two real options, and you might want to do both: Dynamically add a runtime requires on the required version if you detect that the optional module is installed but too old. With dzil you can do this with https://metacpan.org/pod/Dist::Zilla::Plugin::DynamicPrereqs. At runtime, ensure that the module satisfies your minimum version if it is present, and if not treat it as if it was not installed. -Dan (resent to list)
