func listParamResolver(r *resource.Resource, p graphql.ResolveParams, params url.Values) (lookup *resource.Lookup, page int, perPage int, err error) { page = 1 // Default value on non HEAD request for perPage is -1 (pagination disabled) perPage = -1 if l := r.Conf().PaginationDefaultLimit; l > 0 { perPage = l } if p, ok := p.Args["page"].(string); ok && p != "" { i, err := strconv.ParseUint(p, 10, 32) if err != nil { return nil, 0, 0, errors.New("invalid `limit` parameter") } page = int(i) } if l, ok := p.Args["limit"].(string); ok && l != "" { i, err := strconv.ParseUint(l, 10, 32) if err != nil { return nil, 0, 0, errors.New("invalid `limit` parameter") } perPage = int(i) } if perPage == -1 && page != 1 { return nil, 0, 0, errors.New("cannot use `page' parameter with no `limit' paramter on a resource with no default pagination size") } lookup = resource.NewLookup() if sort, ok := p.Args["sort"].(string); ok && sort != "" { if err := lookup.SetSort(sort, r.Validator()); err != nil { return nil, 0, 0, fmt.Errorf("invalid `sort` parameter: %v", err) } } if filter, ok := p.Args["filter"].(string); ok && filter != "" { if err := lookup.AddFilter(filter, r.Validator()); err != nil { return nil, 0, 0, fmt.Errorf("invalid `filter` parameter: %v", err) } } if params != nil { if filter := params.Get("filter"); filter != "" { if err := lookup.AddFilter(filter, r.Validator()); err != nil { return nil, 0, 0, fmt.Errorf("invalid `filter` parameter: %v", err) } } } return }