webClient build url wrong when using UriBuilder [probably a bug]

affects

path = "http://a.b/c";
webClient = WebClient.builder().build();
webClient.get()
        .uri(uriBuilder -> uriBuilder.path(path).queryParams(myMutliValuedMapParams).build());

uri becomes: “http:/a.b/c”, the double slash after schema becomes a single slash. And results in an java.net.UnknownHostException: http: But webClient.get().uri(path); does not have the same problem.

possible reason

UriComponentsBuilder.java buildInternal function causes the problem. the var uric is wrong.

private UriComponents buildInternal(EncodingHint hint) {
		UriComponents result;
		if (this.ssp != null) {
			result = new OpaqueUriComponents(this.scheme, this.ssp, this.fragment);
		}
		else {
// The PROBLEM: 
			HierarchicalUriComponents uric = new HierarchicalUriComponents(this.scheme, this.fragment,
					this.userInfo, this.host, this.port, this.pathBuilder.build(), this.queryParams,
					hint == EncodingHint.FULLY_ENCODED); 

			result = hint == EncodingHint.ENCODE_TEMPLATE ? uric.encodeTemplate(this.charset) : uric;
		}
		if (!this.uriVariables.isEmpty()) {
			result = result.expand(name -> this.uriVariables.getOrDefault(name, UriTemplateVariables.SKIP_VALUE));
		}
		return result;
	}

version

spring-web-5.1.8.RELEASE

[bclozel]

I believe the : character is illegal in path segment. Maybe this section of the reference documentation on URL encoding is of interest?

[bclozel]

@miguel-botelho I understand now - we are indeed sanitizing the path and removing duplicate"/". This is a long standing behavior and I’m not sure we can easily change this now. Feel free to create a new issue, giving as much background information about this use case: why APIs are requiring this format, how common they are (any public one is a plus) and also the limitations of this approach as explained in the RFC.