Fix custom response templating

[manofthepeace]

References

fixes #2349

when manually creating a ResponseTemplateTransformer via WireMockConfiguration.extentions. It gets added to the loadedExtensions, but then gets overwritten by the put.

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[oleg-nenashev]

Looks about right. If you could create a test case for this regression, it would be awesome

[tomakehurst]

Please could you run ./gradlew spotlessApply so that the tests can be executed?

[manofthepeace]

@tomakehurst done

[manofthepeace]

@oleg-nenashev I have added a simple test that would fail without the PR.

[tomakehurst]

Not a necessary fix per #2349 (comment).

Documentation will be updated soon to reflect the new, simplified way to enable templating.

[oleg-nenashev]

@tomakehurst so it would be a new documented breaking change, right?

[tomakehurst]

Yes, will add to the release note and update the main doc in due course.

[manofthepeace]

@tomakehurst can you please re-evaluate. As an end user I find it a really hard to use behaviour. globalTemplating /global is one thing. But I need to have to customize the templateEngine, which I then need to put in the ResponseTemplateTransformer.

        WireMockConfiguration config = new WireMockConfiguration();
        FileSource fs = new ClasspathFileSource("src/test/resources/mocks/");
        TemplateEngine engine = new TemplateEngine(Map.of("json", Jackson2Helper.INSTANCE), null, null, true);
        config = config.port(9094).fileSource(fs)
                .extensions(new ResponseTemplateTransformer(engine, true, fs, Collections.emptyList()));
        wireMockServer = new WireMockServer(config);
        wireMockServer.start();

Why if I make the effort of specifying the ResponseTemplateTransformer myself, wiremocks just goes ahead and replaces it with its default implementation..

[tomakehurst]

Again, I think the docs need improving here - if you want to add custom helpers you do it via another extension point now:
https://wiremock.org/docs/extensibility/adding-template-helpers/

It shouldn't ever be necessary as an end user to new up your own ResponseTemplateTransformer now. If there's anything that can't be customised via an extension or config param, we should be making these available instead.

[manofthepeace]

OK, I can confirm all this is working as you said right above. Thanks for that, I totally missed that doc page. I think this should be noted in the migration steps of the release page. Since before we had to create the ResponseTemplateTransfomer, it seems sort of natural to still create by using the api available, which I went too far in the rabbit hole to adapt to the internal stuff that possible shoudn't be touched