Redirect Attributes

By default, all model attributes are considered to be exposed as URI template variables in the redirect URL. Of the remaining attributes, those that are primitive types or collections or arrays of primitive types are automatically appended as query parameters.

Appending primitive type attributes as query parameters can be the desired result if a model instance was prepared specifically for the redirect. However, in annotated controllers, the model can contain additional attributes added for rendering purposes (for example, drop-down field values). To avoid the possibility of having such attributes appear in the URL, a @RequestMapping method can declare an argument of type RedirectAttributes and use it to specify the exact attributes to make available to RedirectView. If the method does redirect, the content of RedirectAttributes is used. Otherwise, the content of the model is used.

The RequestMappingHandlerAdapter provides a flag called ignoreDefaultModelOnRedirect, which you can use to indicate that the content of the default Model should never be used if a controller method redirects. Instead, the controller method should declare an attribute of type RedirectAttributes or, if it does not do so, no attributes should be passed on to RedirectView. Both the MVC namespace and the MVC Java configuration keep this flag set to false, to maintain backwards compatibility. However, for new applications, we recommend setting it to true.

Note that URI template variables from the present request are automatically made available when expanding a redirect URL, and you don’t need to explicitly add them through Model or RedirectAttributes. The following example shows how to define a redirect:

  • Java

  • Kotlin

@PostMapping("/files/{path}")
public String upload(...) {
	// ...
	return "redirect:files/{path}";
}
@PostMapping("/files/{path}")
fun upload(...): String {
	// ...
	return "redirect:files/{path}"
}

Another way of passing data to the redirect target is by using flash attributes. Unlike other redirect attributes, flash attributes are saved in the HTTP session (and, hence, do not appear in the URL). See Flash Attributes for more information.