API versioning is essential in managing changes and ensuring backward compatibility in Spring Boot applications. There are several strategies to handle API versioning:

  • URI Path Versioning:
    • The version is included directly in the URL path.
    @RestController
@RequestMapping("/api/v1/users")
public class UserControllerV1 {
    @GetMapping
    public List<User> getUsers() {
        return userService.getUsers();
    }
}
    • Pros: Simple and clear versioning strategy.
    • Cons: Can lead to messy URLs as versions increase.
  • Request Param Versioning:
    • Version is specified as a query parameter in the URL.
    @RestController
@RequestMapping("/api/users")
public class UserController {
    @GetMapping(params = "version=1")
    public List<User> getUsersV1() {
        return userService.getUsersV1();
    }
}
    • Pros: More flexible and less intrusive to the URL structure.
    • Cons: Can lead to confusion if multiple versions are used in the same controller.
  • Header Versioning:
    • Version is specified in the request header.
    @RestController
public class UserController {
    @RequestMapping(value = "/api/users", headers = "API-Version=1", method = RequestMethod.GET)
    public List<User> getUsersV1() {
        return userService.getUsersV1();
    }
}
    • Pros: Clean URL, keeps versioning logic separate from the URL.
    • Cons: Requires custom logic or libraries for processing headers.
  • Accept Header (Content Negotiation):
    • Version is specified via the Accept header.
    @RestController
@RequestMapping("/api/users")
public class UserController {
    @GetMapping(produces = "application/vnd.company.api-v1+json")
    public List<User> getUsersV1() {
        return userService.getUsersV1();
    }
}
    • Pros: Elegant and clean versioning solution, well-supported in Spring.
    • Cons: Can be more complex for clients to implement and understand.

In summary, API versioning in Spring Boot can be managed through URI path, request parameters, headers, or content negotiation, depending on your needs and how explicit or flexible you want versioning to be.