Common web

The common-web module holds small parts for Javalin web apps. Discord OAuth uses them.

implementation("dev.chojo.aether:common-web:2.0.0")

Errors

ApiException is a runtime exception with an HTTP status. Throw it in a handler and turn it into a response in one place:

app.exception(ApiException.class, (e, ctx) ->
        ctx.status(e.status()).json(new ErrorResponseWrapper(e.status().getMessage(), e.getMessage())));

app.get("/guilds/{id}", ctx -> {
    Guild guild = jda.getGuildById(ctx.pathParam("id"));
    if (guild == null) throw new ApiException(HttpStatus.NOT_FOUND, "Unknown guild");
    ctx.json(guild);
});

ErrorResponseWrapper holds an error title, a message and optional details, written as JSON fields of the same names.

Query strings

Urls.splitQuery("a=1&b=2") splits a query string into a map and decodes the keys and values. A parameter without a value (a&b=2) maps to an empty string. A parameter that appears twice keeps its last value.