Reputation: 3854
What is the preferred way to specify an HTTP "Location" Response Header in Spring MVC 3?
As far as I can tell, Spring will only provide a "Location" in response to a redirect ("redirect:xyz" or RedirectView), however there are scenarios where a Location should be sent along with the entity body (ex, as a result of a "201 Created").
I'm afraid my only option is manually specifying it:
httpServletResponse.setHeader("Location", "/x/y/z");
Is this correct? Is there a better way to tackle this problem?
Upvotes: 45
Views: 54270
Reputation: 15881
The key point is to use UriComponentsBuilder
.
There are several ways how you can get the instance of it
UriComponentsBuilder
from MvcUriComponentsBuilder
UriComponentsBuilder
injected as parameter to methodUriComponentsBuilder
from MvcUriComponentsBuilder
This way you can get UriComponentsBuilder
that is configured to produce URI
that points to some controller methods with predefined parameters.
Here is example from the javadoc for MvcUriComponentsBuilder
:
For example, given this controller:
@RequestMapping("/people/{id}/addresses")
class AddressController {
@RequestMapping("/{country}")
public HttpEntity<Void> getAddressesForCountry(@PathVariable String country) { ... }
@RequestMapping(value="/", method=RequestMethod.POST)
public void addAddress(Address address) { ... }
}
A UriComponentsBuilder can be created:
// Inline style with static import of "MvcUriComponentsBuilder.on"
MvcUriComponentsBuilder.fromMethodCall(
on(AddressController.class).getAddressesForCountry("US")).buildAndExpand(1);
Another options which sometimes may be preferable is to specify controller method by name:
UriComponents uriComponents = MvcUriComponentsBuilder.fromMethodName(
AddressController.class, "getAddressesForCountry", "US").buildAndExpand(1);
URI nextUri = uriComponents.toUri();
UriComponentsBuilder
injected as parameter to methodAs of spring 3.1 Location
can be crafted using UriComponentBuilder
parameter and set it to the returned ResponseEntity
. UriComponentBuilder
is aware of the context and manipulates with relative paths:
@RequestMapping(method = RequestMethod.POST)
public ResponseEntity<?> createCustomer(UriComponentsBuilder b) {
UriComponents uriComponents =
b.path("/customers/{id}").buildAndExpand(id);
HttpHeaders headers = new HttpHeaders();
headers.setLocation(uriComponents.toUri());
return new ResponseEntity<Void>(headers, HttpStatus.CREATED);
}
Since version 4.1 you can make it even shorter
@RequestMapping(method = RequestMethod.POST)
public ResponseEntity<?> createCustomer(UriComponentsBuilder b) {
UriComponents uriComponents =
b.path("/customers/{id}").buildAndExpand(id);
return ResponseEntity.created(uriComponents.toUri()).build();
}
Thanks to Dieter Hubau to pointing this out.
Upvotes: 103
Reputation: 2982
It's an old question but here is what you can do if you want to let Spring really build the URI for you.
@RestController
@RequestMapping("/api/v1")
class JobsController {
@PostMapping("/jobs")
fun createJob(@RequestParam("use-gpu") useGPU: Boolean?): ResponseEntity<Unit> {
val headers = HttpHeaders()
val jobId = "TBD id"
headers.location =
MvcUriComponentsBuilder
.fromMethodName(JobsController::class.java, "getJob", jobId)
.buildAndExpand(jobId)
.toUri()
return ResponseEntity(headers, HttpStatus.CREATED)
}
@GetMapping("/job/{jobId}")
fun getJob(@PathVariable jobId: String) = ... // fetch job
}
In this example (which is written in Kotlin but similar for java), the base URI is /api/v1
(defined at the top of the class). Using MvcUriComponentsBuilder.fromMethodName
call lets Spring figure out the proper full URI. (MvcUriComponentsBuilder
was added in 4.0).
Upvotes: 6
Reputation: 11233
The following example is from spring tutorial:
@RequestMapping(method = RequestMethod.POST)
ResponseEntity<?> add(@PathVariable String userId, @RequestBody Bookmark input) {
this.validateUser(userId);
return this.accountRepository
.findByUsername(userId)
.map(account -> {
Bookmark result = bookmarkRepository.save(new Bookmark(account,
input.uri, input.description));
URI location = ServletUriComponentsBuilder
.fromCurrentRequest().path("/{id}")
.buildAndExpand(result.getId()).toUri();
return ResponseEntity.created(location).build();
})
.orElse(ResponseEntity.noContent().build());
}
Take note that the following will compute the context path (URI) for you avoiding code duplication and making your application more portable:
ServletUriComponentsBuilder
.fromCurrentRequest().path("/{id}")
Upvotes: 41
Reputation: 13473
Your approach seems fine, but to keep it clean you could put the code inside a custom HandlerInterceptor
that only triggers when there's an HTTP 201, for example.
See here for more information.
Upvotes: 1
Reputation: 2084
According to: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.30
Absolute URI should be used:
Location = "Location" ":" absoluteURI
And the URI should be escaped properly:
http://www.ietf.org/rfc/rfc2396.txt
Upvotes: 2