UriTemplate unconditionally percent-encodes literal part

[bodewig]

Affects: 5.2.1 and earlier

When using UriTemplate with a properly percent-encoded literal part, the percent sign gets encoded a second time. For example

new UriTemplate("https://example.org/foo%20and%20bar/{baz}").expand("xyzzy")

yields https://example.org/foo%2520and%2520bar/xyzzy rather than the expected https://example.org/foo%20and%20bar/xyzzy.

UriTemplate's constructor uses UriComponentsBuilder.build() without any arguments. One option could be to provide a second constructor with a boolean encoded argument mirroring the one-arg version of UriComponentsBuilder.build(). If this sounds like a useful addition I can create a small PR.

[rstoyanchev]

UriTemplate is a thin wrapper around UriComponentsBuilder that exists for historic reasons, so why not bypass it altogether? That said your requirement can't be expressed with boolean flag because then "{" and "}" are invalid characters and UriComponents will flag them.

UriBuilderFactory provides another thin layer over UriComponentsBuilder with multiple options for encoding. It could be used like this for this use case:

DefaultUriBuilderFactory factory = new DefaultUriBuilderFactory();
factory.setEncodingMode(EncodingMode.VALUES_ONLY);

URI url = factory.uriString("https://example.org/foo%20and%20bar/{baz}").build("xyzzy");

Also see the reference on URI Links.

[rstoyanchev]

Closing but feel free to comment.

[bodewig]

Many thanks @rstoyanchev I agree this is the better approach.

Actually I've been using UriTemplate transitively via Spring HATEOAS - and @odrotbohm has already taken your advice and fixed things over there. I really appreciate both of you taking time for this.