Ejemplo n.º 1
0
// FilterFunc  Filter out Values that match specified list of match filter criteria
//
//   - Operates on MapValue (map[string]interface{}), StringsValue ([]string), or string
//   - takes N Filter Criteria
//   - supports Matching:      "filter*" // matches  "filter_x", "filterstuff"
//
//  -- Filter a map of values by key to remove certain keys
//    filter(match("topic_"),key_to_filter, key2_to_filter)  => {"goodkey": 22}, true
//
// -- Filter out VALUES (not keys) from a list of []string{} for a specific value
//    filter(split("apples,oranges",","),"ora*")  => ["apples"], true
//
// -- Filter out values for single strings
//    filter("apples","app*")      => []string{}, true
//
func FilterFunc(ctx expr.EvalContext, val value.Value, filterVals ...value.Value) (value.Value, bool) {

	filters := FiltersFromArgs(filterVals)

	//u.Debugf("Filter():  %T:%v   filters:%v", val, val, filters)
	switch val := val.(type) {
	case value.MapValue:

		mv := make(map[string]interface{})

		for rowKey, v := range val.Val() {
			filteredOut := false
			for _, filter := range filters {
				if strings.Contains(filter, "*") {
					match, _ := glob.Match(filter, rowKey)
					if match {
						filteredOut = true
						break
					}
				} else {
					if strings.HasPrefix(rowKey, filter) && v != nil {
						filteredOut = true
						break
					}
				}
			}
			if !filteredOut {
				mv[rowKey] = v.Value()
			}
		}

		return value.NewMapValue(mv), true

	case value.StringValue:
		anyMatches := false
		for _, filter := range filters {
			if strings.Contains(filter, "*") {
				match, _ := glob.Match(filter, val.Val())
				if match {
					anyMatches = true
					break
				}
			} else {
				if strings.HasPrefix(val.Val(), filter) {
					anyMatches = true
					break
				}
			}
		}
		if anyMatches {
			return value.NilValueVal, true
		}
		return val, true
	case value.StringsValue:
		lv := make([]string, 0, val.Len())
		for _, sv := range val.Val() {
			filteredOut := false
			for _, filter := range filters {
				if strings.Contains(filter, "*") {
					match, _ := glob.Match(filter, sv)
					if match {
						filteredOut = true
						break
					}
				} else {
					if strings.HasPrefix(sv, filter) && sv != "" {
						filteredOut = true
						break
					}
				}
			}
			if !filteredOut {
				lv = append(lv, sv)
			}
		}

		return value.NewStringsValue(lv), true

	default:
		u.Warnf("unsuported key type: %T %v", val, val)
	}

	//u.Warnf("could not find key: %T %v", item, item)
	return nil, false
}