Q: Support for queryParam() and formParam() with default values - removed in 4.x API

Effectively #1291 introduces a breaking API change for queryParam() and formParam() that take a default value.

Previous API was:

      String myParam = ctx.queryParam("my-param", "one");

I believe this now needs to use a Validator and needs to be written as:

      String myParam = ctx.queryParamAsClass("my-param", String.class).getOrDefault("one");

Is that correct, have I missed something?

Noting that for people like myself that prefer external validation and are not interested in using Javalin Validation this API change appears to be a step backwards. Noting that it is pretty common for queryParam and formParam to have default values and this is now incurs some extra runtime overhead along with a difference in style when a default value is desired.

Maybe I have missed something. It looks to me like the API for queryParam/formParam that takes a default value as String could be re-instated for backward compatibility given the queryParamAsClass() validator approach of 1291. What are the thoughts on that?

Thanks, Rob.

[tipsy]

I’ll close this for now, but would be willing to consider xyzOrDefault methods if someone wants them enough to provide a PR.

[tipsy]

Is that correct, have I missed something?

You are correct, these methods were removed on purpose. They only existed for some methods, and I thought adding this as part of validation made more sense than keeping it in the base API. If a user just wants a default value, that’s pretty easily achieved by Optional.ofNullable(ctx.queryParam("key")).orElse("value");, or ctx.queryParam("key") ?: "value" - does this need to be part of the base API?

It looks to me like the API for queryParam/formParam that takes a default value as String could be re-instated for backward compatibility given the queryParamAsClass() validator approach of 1291. What are the thoughts on that?

I’ve never been a fan of ctx.queryParam("key", "default");, I don’t think it reads well, so I would rather keep it out. I think Optional.ofNullable(ctx.queryParam("key")).orElse("value"); reads better than ctx.queryParam("key", "value").