Fix polymorphism in Translator

[marc-vanderwal]

Purpose

This PR fixes some regressions, presumably introduced by #1319, that could not be caught in Zonemaster::Engine’s unit tests.

Context

Problems

In Zonemaster::Backend, there is a Zonemaster::Backend::Translator class which inherits from Zonemaster::Engine::Translator. This is done in order to override the translate_tag method with a custom version.

When “un-Moosing” Zonemaster::Engine, however, changes were introduced that were harmless for Zonemaster::Engine, but not for Zonemaster::Backend. This caused two issues to emerge:

• firstly, commands such as zmb get_test_results, that rely on translating messages pulled from the database, stopped working;
• secondly, messages generated by the backend itself were no longer translated.

Cause

The root cause of the first problem is that when calling Zonemaster::Backend::Translator->new(), the newly-created instance was always blessed as Zonemaster::Engine::Translator (the superclass), not as the inheriting class. Thus, translate_tag() method calls always called the method in the superclass instead of the inheriting class.

As for the second problem, this is due to Backend’s Translator overriding another method, _build_all_tag_descriptions, from Engine’s Translator, and the initialization code in Zonemaster::Engine::Translator failing to call the overridden _build_all_tag_description when invoked as the Backend’s Translator class.

Changes

• In the constructor, instead of blessing with __PACKAGE__ (a macro that always expands to Zonemaster::Engine::Translator), bless with $class instead.
• Make the _build_all_tag_descriptions subroutine a proper class method and have initialize hand over to the method of the correct class.

How to test this PR

1. Make sure Ensure Backend’s messages stay translated zonemaster-backend#1166 is merged first.

2. Run a test with zmb and grab the test ID (or have a test ID of a previous test handy and skip the following command):

TEST_ID=`zmb start_domain_test --domain localhost | jq -r .result`

3. Then, run the following after the test is done:

zmb get_test_results --lang fr --test-id $TEST_ID | jq -e .result.params.domain

This command should print "localhost" (or whatever the domain under test was) and set an exit status of 0. Any other result, or null, is abnormal.

4. Using zmtest, run a test on a domain name that causes Zonemaster to time out, such as pool.ntp.org. The error message stating that the test took too long to complete should be translated (i.e., the raw untranslated message tag must not appear).

[matsduf]

In the "how to test" it should be jq -r .result not jq -r result, at least with the jq I have.

[marc-vanderwal]

In the "how to test" it should be jq -r .result not jq -r result, at least with the jq I have.

That’s because it was a typo. I’ve fixed the procedure.

[mattias-p]

Release testing for v2024.1

I've tested this according to the testing instruction above with successful results.