53 lines
748 B
Go
53 lines
748 B
Go
package parser
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import (
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"encoding/json"
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"errors"
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"strconv"
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)
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const (
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minId = 1
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maxId = 20 * 1000 * 1000
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)
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type Id int32
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func (id *Id) UnmarshalJSON(b []byte) error {
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if len(b) > 0 && b[0] != '"' {
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if err := id.unmarshalInt(b); err != nil {
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return err
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}
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} else {
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if err := id.unmarshalString(b); err != nil {
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return err
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}
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}
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if *id < minId || *id > maxId {
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return errors.New("json: id is invalid")
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}
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return nil
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}
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func (id *Id) unmarshalInt(b []byte) error {
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return json.Unmarshal(b, (*int32)(id))
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}
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func (id *Id) unmarshalString(b []byte) error {
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var s string
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if err := json.Unmarshal(b, &s); err != nil {
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return err
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}
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i, err := strconv.Atoi(s)
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if err != nil {
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return err
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}
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*id = Id(i)
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return nil
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}
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