spring中解決CROS跨域請求的方案

感覺spring真是個強大的框架，解決這種棘手的問題很簡單，參考官方文檔：

Controller method CORS configuration

You can add to your @RequestMapping annotated handler method a @CrossOriginannotation in order to enable CORS on it (by default @CrossOrigin allows all origins and the HTTP methods specified in the @RequestMapping annotation):

@RestController
@RequestMapping("/account")
public class AccountController {

	@CrossOrigin
	@GetMapping("/{id}")
	public Account retrieve(@PathVariable Long id) {
		// ...
	}

	@DeleteMapping("/{id}")
	public void remove(@PathVariable Long id) {
		// ...
	}
}

It is also possible to enable CORS for the whole controller:

@CrossOrigin(origins = "http://domain2.com", maxAge = 3600)
@RestController
@RequestMapping("/account")
public class AccountController {

	@GetMapping("/{id}")
	public Account retrieve(@PathVariable Long id) {
		// ...
	}

	@DeleteMapping("/{id}")
	public void remove(@PathVariable Long id) {
		// ...
	}
}

In this example CORS support is enabled for both retrieve() and remove() handler methods, and you can also see how you can customize the CORS configuration using @CrossOrigin attributes.

You can even use both controller and method level CORS configurations, Spring will then combine both annotation attributes to create a merged CORS configuration.

@CrossOrigin(maxAge = 3600)
@RestController
@RequestMapping("/account")
public class AccountController {

	@CrossOrigin(origins = "http://domain2.com")
	@GetMapping("/{id}")
	public Account retrieve(@PathVariable Long id) {
		// ...
	}

	@DeleteMapping("/{id}")
	public void remove(@PathVariable Long id) {
		// ...
	}
}