As the title says.
I basically would love to do requests like
/api/todos/?completed=eq.true&created_at=lt.1486462109399
Is there any ready spring way of achieving such? Something akin to the Page/Pageable mechanism would be great.
If there is none I think I could implement it using Hibernate Criteria Queries & Argument Re-solvers. Basically allowing me to write my controllers like
@GetMapping
public ResponseEntity<Page<TodoDTO>> listAll(Criteria criteria, Pageable pageable)
{
Page<Todo> todos = todoService.listAll(criteria, pageable)
...
}
A custom Argument resolver would be responsible for turning the query string into a Criteria. Not quite sure yet how I would handle it within the service but that's the direction in which I would try to implement this.
Would that be a good approach? Any recommendations? (All assuming there are no ready mechanism for such already).
Your help is much appreciated.
Another option to build a fluent query API is to use a RSQL parser. RSQL is a query language for parametrized filtering of entries in RESTful APIs. Follow this article and your API would be able to handle URLs like:
http://localhost:8080/users?search=firstName==jo*;age<25
Sample controller:
@RestController
@RequestMapping(value = "/users")
public class UserController {
@Autowired
private UserRepository repo;
@GetMapping
public List<User> findAllByRsql(@RequestParam(value = "search") String search) {
Node rootNode = new RSQLParser().parse(search);
Specification<User> spec = rootNode.accept(new CustomRsqlVisitor<User>());
return repo.findAll(spec);
}
}
Gradle dependency:
// https://mvnrepository.com/artifact/cz.jirutka.rsql/rsql-parser
implementation("cz.jirutka.rsql:rsql-parser:2.1.0")
Recommendations from the library author:
I recommend to use separate URI query parameter for sorting, e.g.
?query=name==Flynn&sortBy=name, not to mix it with RSQL expression. The same applies to paging; I recommend URI parameters namedlimitandoffset.