Invalid query parameters when using Pageable as argument to declarative http client

[Uniqen]

It would be very usable if Pageable was converted to the correct query parameters when used with the declarative http client. For example for an API-gateway that should just forward the request or when writing tests. This would also make it possible to share a common interface between Controller and Client.

The problem as I see it is to make it a non breaking change or is there a way to configure how the query parameters is resolved that I don't know about?

Steps to Reproduce

1. Create Controller with Pageable as argument

   @Controller("/pets")
   class PetController {
   @Get("/{?pageable*}") // No really needed but for symmetrical 
   List<NameDTO> all(Pageable pageable) {
       return petRepository.list(pageable);
   }
   }

2. Create corresponding declarative http client

   @Client("/pets")
   public interface PetClient {
   @Get("/{?pageable*}")
   List<NameDTO> all(Pageable pageable);
   }

3. Use client to invoke controller.

   List<NameDTO> results = petClient.all(Pageable.from(1,1).order("name", DESC));

   Expected Behaviour

   The pageable should be sent using the query parameters page, size and sort: GET /parent/?size=1&sort=name%2CDESC&page=1

Actual Behaviour

The query string is invalid (both page (sent as number) and sort) plus som additional irrelevant parameters. GET /pets/?sort=io.micronaut.data.model.DefaultSort%40f331e9d7&sorted=true&number=1&orderBy=io.micronaut.data.model.Sort%24Order%40f331e999&offset=1&size=1

And then an exception is raised on the server side since the sorting is invalid:

21:23:05.541 [pool-2-thread-2] ERROR i.m.h.s.netty.RoutingInBoundHandler - Unexpected error occurred: Cannot sort on non-existent property path: io.micronaut.data.model.DefaultSort@f331e9d7
java.lang.IllegalArgumentException: Cannot sort on non-existent property path: io.micronaut.data.model.DefaultSort@f331e9d7
    at io.micronaut.data.model.query.builder.AbstractSqlLikeQueryBuilder.lambda$buildOrderBy$35(AbstractSqlLikeQueryBuilder.java:1310)
    at java.util.Optional.orElseThrow(Optional.java:290)
    at io.micronaut.data.model.query.builder.AbstractSqlLikeQueryBuilder.buildOrderBy(AbstractSqlLikeQueryBuilder.java:1310)
    at io.micronaut.data.hibernate.operations.HibernateJpaOperations.lambda$findAll$6(HibernateJpaOperations.java:252)
    at io.micronaut.transaction.support.AbstractSynchronousTransactionManager.executeRead(AbstractSynchronousTransactionManager.java:157)
    at io.micronaut.data.hibernate.operations.HibernateJpaOperations.findAll(HibernateJpaOperations.java:245)
    at io.micronaut.data.runtime.intercept.DefaultFindAllInterceptor.intercept(DefaultFindAllInterceptor.java:52)
    at io.micronaut.data.runtime.intercept.DefaultFindAllInterceptor.intercept(DefaultFindAllInterceptor.java:36)
    at io.micronaut.data.intercept.DataIntroductionAdvice.intercept(DataIntroductionAdvice.java:78)
    at io.micronaut.aop.chain.MethodInterceptorChain.proceed(MethodInterceptorChain.java:69)
    at example.repositories.PetRepository$Intercepted.list(Unknown Source)
    at example.controllers.PetController.all(PetController.java:24)
...

Environment Information

• Operating System: Mac OS 10.14.3
• Micronaut Version: 1.2.3
• Micronaut Data Version: 1.0.0.M3
• JDK Version: 8.0.222

Example Application

• See https://github.com/Uniqen/micronaut-predator/tree/pageable_as_query_parameter
• Or just the relevant commit https://github.com/Uniqen/micronaut-predator/commit/619bcf54d4061cf4b4658cc96da297f3c8670a1f

[graemerocher]

This would be nice. Currently the client implementation is not flexible enough to allow custom encoding of arguments. So we would need an improvement in Micronaut Core first to implement this.

[Uniqen]

I've duplicated the Pageable (and DefaultPageable, Sort, DefaultSort) as a workaround until it is resolved. This still blocks sharing interface between Client and Controller but at least makes it easy to use in tests and api gateway.

@Controller("/pets")
class PetGatewayController {
    @Get("/{?pageable*}")
    List<NameDTO> all(Pageable pageable) {
        return petClient.all(PageableQuery.from(pageable));
    }
}

@Client("/pets")
public interface PetClient {
    @Get("/{?pageable*}")
    List<NameDTO> all(PageableQuery pageable);
}

//Usage in tests is the same as Pageable
PageableQuery pageable = PageableQuery.from(1, 1)
    .order("name", DESC);
List<NameDTO> results = petClient.all(pageable);

If anyone else is interested in the workaround see commit: https://github.com/Uniqen/micronaut-predator/commit/37147347b4e1c6d59d2816e658c3ba9d6ed623d0

[njimenezotto]

Another option is to pass to the @Client the values of the Pageable like this:

@QueryValue("size") int size,
@QueryValue("number") int number

And the @Controller can still declare the

@QueryValue("pageable") Pageable page

[regine-chan]

Any updates on this? Would be terrific to be able to share interface between controllers and clients.

[graemerocher]

In Micronaut 4 we added support for custom message writers so maybe it is possible now

[Hc747]

Bumping this - any updates for Pageable parameters within @Controller methods?