如何在Spring Rest @PathVariable中正确转义'/'

Question

In Spring Boot 1.5.4 I have a request mapping like this:

@RequestMapping(value = "/graph/{graphId}/details/{iri:.+}", 
                method = RequestMethod.GET,
                produces = MediaType.APPLICATION_JSON_VALUE)
@Timed
public JSONObject getGraph(@PathVariable Long graphId, 
                           @PathVariable String iri) {
    log.debug("Details called for graph ID {} for IRI {}", graphId, iri);
    return detailsService.getDetails(graphId, iri);
}

Accessing

http://localhost:9000/api/v1/graph/2/details/http%3Anthnth33

works fine and the server maps the request correctly and the code returns the expected result

But accessing

http://localhost:9000/api/v1/graph/2/details/http%3A%2F%2Fserverurl.net%2Fv1%2Fus%2Fh.schumacher%408tsch.net%2Fn%2FLouSchumacher

gives a bad server request (Failed to load resource: the server responded with a status of 400 (Bad Request)). The request mapping to the end point isn't even done in that case.

Obviously the slash '/' encoded as %2F (using encodeURIComponent()) causes trouble. Why? What am I missing? How should uri parameter then be encoded?

The question is not only about how to extract PathVariables but more on how to force String to recognize the correct mapping.

Answer 1

The issue with your example is how Spring is doing path matching. The URL you have provided as example

http://localhost:9000/api/v1/graph/2/details/http%3A%2F%2Fserverurl.net%2Fv1%2Fus%2Fh.schumacher%408tsch.net%2Fn%2FLouSchumacher

will be decoded into by container

http://localhost:9000/api/v1/graph/2/details/http://serverurl.net/v1/us/h.schumacher@8tsch.net/n/LouSchumacher

before processing by Spring matcher. This makes matche think that this only http: corresponds {iri:.+} and as later goes / so it is some longer path you don't have a mapping for.

The approach described here should work for you: Spring 3 RequestMapping: Get path value

@RequestMapping(value = "/graph/{graphId}/details/**", 
                method = RequestMethod.GET,
                produces = MediaType.APPLICATION_JSON_VALUE)
@Timed
public JSONObject getGraph(@PathVariable Long graphId, 
                           HttpServletRequest request) {
    String iri = (String) request.getAttribute(
        HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);
    log.debug("Details called for graph ID {} for IRI {}", graphId, iri);
    return detailsService.getDetails(graphId, iri);
}