filters.go

package godruid

type Filter struct {
	Type      string      `json:"type"`
	Dimension string      `json:"dimension,omitempty"`
	Value     interface{} `json:"value,omitempty"`
	Pattern   string      `json:"pattern,omitempty"`
	Function  string      `json:"function,omitempty"`
	Field     *Filter     `json:"field,omitempty"`
	Fields    []*Filter   `json:"fields,omitempty"`
}

func FilterSelector(dimension string, value interface{}) *Filter {
	return &Filter{
		Type:      "selector",
		Dimension: dimension,
		Value:     value,
	}
}

func FilterRegex(dimension, pattern string) *Filter {
	return &Filter{
		Type:      "regex",
		Dimension: dimension,
		Pattern:   pattern,
	}
}

func FilterJavaScript(dimension, function string) *Filter {
	return &Filter{
		Type:      "javascript",
		Dimension: dimension,
		Function:  function,
	}
}

func FilterAnd(filters ...*Filter) *Filter {
	return joinFilters(filters, "and")
}

func FilterOr(filters ...*Filter) *Filter {
	return joinFilters(filters, "or")
}

func FilterNot(filter *Filter) *Filter {
	return &Filter{
		Type:  "not",
		Field: filter,
	}
}

func joinFilters(filters []*Filter, connector string) *Filter {
	// Remove null filters.
	p := 0
	for _, f := range filters {
		if f != nil {
			filters[p] = f
			p++
		}
	}
	filters = filters[0:p]

	fLen := len(filters)
	if fLen == 0 {
		return nil
	}
	if fLen == 1 {
		return filters[0]
	}

	return &Filter{
		Type:   connector,
		Fields: filters,
	}
}