44 lines
970 B
Go
44 lines
970 B
Go
package json
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import (
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"fmt"
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"strconv"
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"strings"
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)
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func Query(parent Node, path []string) (Node, error) {
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if len(path) == 0 {
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return parent, nil
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}
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head, rest := path[0], path[1:]
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switch parent := parent.(type) {
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case ObjectNode:
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next, ok := parent.GetByKey(head)
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if !ok {
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return nil, fmt.Errorf("key %s not found at object %v", head, parent)
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}
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return Query(next, rest)
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case ArrayNode:
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stringIdx := strings.Trim(head, "[]")
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idx, err := strconv.Atoi(stringIdx)
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if err != nil {
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return nil, fmt.Errorf("key %s is invalid index: %w", stringIdx, err)
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}
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if idx >= parent.Len() {
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return nil, fmt.Errorf("index %d is out of range (len=%d)", idx, parent.Len())
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}
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next := parent.Index(idx)
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return Query(next, rest)
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default:
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return nil, fmt.Errorf("can't get key=%s from node type = %t", head, parent)
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}
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}
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func MustQuery(parent Node, path []string) Node {
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n, err := Query(parent, path)
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if err != nil {
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panic(err)
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}
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return n
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}
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