Different template engine about openapi-codegen

[MikeRalphson]

v2.1.0 allows you to set a generator property with a render function in the config. See #118 for details.

[iilyak]

Thank you for merging the feature.

[iilyak]

Actually according to https://github.com/swagger-api/swagger-codegen/releases/tag/v3.0.0-rc0 the swagger-api switched to handlebarjs.

[MikeRalphson]

We use hogan.js here as it was the only js template engine which actually worked with the Swagger-Codegen 2.3 templates we imported.

See https://github.com/wycats/handlebars.js/blob/master/README.markdown#compatibility for a list of reasons why handebarsjs is not currently an option.

Maybe you could write a plugin for prettier or something for your target language?

Alternatively the new custom lambda support might help you refractor your templates.

[iilyak]

what if we would support both? We could choose the engine based on file extension. If it .mustache we would choose hogan. If it is .hbr we would select handlebars.

[MikeRalphson]

Can you point me to docs which confirm handlebars supports controlling whitespace?

[iilyak]

https://handlebarsjs.com/guide/expressions.html#whitespace-control

[iilyak]

Implementation wise it is quite easy. I patched openapi-codegen in few places and successfully using it in my project.

const Handlebars = require('handlebars');

....
Handlebars.registerHelper(lambda, generator.lambdas[lambda]);
....
Handlebars.registerPartial(p, ff.readFileSync(tpl(config, configName, partial),'utf8'));
...
let template = Handlebars.compile(action.template);
let content = template(model);

[iilyak]

I can do a PR if you think this feature is useful.

[MikeRalphson]

Are you in a position to also contribute a config and set of templates and a CI test, I.e. Will we have test coverage for this feature?

[iilyak]

I see two options here:

1. create configs/test-hbr.json and templates/test-hbr.hbr
2. create tests/fixtures/configs/test-hbr.json and tests/fixtures/templates/test-hbr.hbr

The test can check that

• the simple .hbr template rendered correctly
• the template in the filename of the target is rendered using engine depending on template file extension

[MikeRalphson]

I would prefer to only add the complexity of supporting multiple rendering engines if we can demonstrate a real-world set of templates that need the functionality. Happy to hear from anyone else who might need the functionality.