How to handle exceptions with Swagger?

Question

I am building some test APIs using swagger (1.5) and JAX-rs with Jersey (1.13) and I m trying to implement exception handling. For example I have the following code when receiving the results from my DB (Elasticsearch)

@POST
@Path("/category")
@ApiOperation(value="returns products")
@Produces({ "application/json" })
public Response getPostCategories( 
        @ApiParam(value="keyphrase, required=true) @QueryParam("keyphrase") String keyphrase,
        @ApiParam(value="category) @QueryParam("category") String category,     
        @Context SecurityContext securityContext) 
throws WebApplicationException {        
    SearchRequest searchRequest = new SearchRequest();
    searchRequest.setKeyphrase(keyphrase);
    searchRequest.setCategory(category);

    SearchCategoryQuery categoryQuery = new SearchCategoryQuery();
    String searchResponse = null;
    try
    {           
        searchResponse = categoryQuery.searchCategory(searchRequest);
    }
    catch (WebApplicationException ex)
    {
        throw new WebApplicationException(Response.status(Status.BAD_REQUEST).entity("results no found").type(javax.ws.rs.core.MediaType.APPLICATION_JSON).build());
    }
    return Response.ok(searchResponse).build();
}

However, in the output swagger always prints the same response

What I need instead is to receive the error messages I specify in each exception. Any ideas?

Answer 1

Swagger by itself does not handle application exceptions as yet.

You will either need to create custom Exception classes (that extend java.lang.exception) or use the existing ones (like WebApplicationException that you are already using) and make the API definition throw these errors. So basically you need to use Java/J2EE/Jersey to throw proper exceptions. Swagger UI will display them for you.

Check this link for details on REST exception handling with Spring.