63 lines
1.2 KiB
Go
63 lines
1.2 KiB
Go
package confection2
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import (
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"encoding/json"
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"log"
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"reflect"
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)
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var (
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// config stores application config.
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config interface{}
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)
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// Manage accepts a pointer to a configuration struct.
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func Manage(target interface{}) {
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if ok := isStructPtr(target); !ok {
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panic("Argument must be a pointer to a struct")
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}
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config = target
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}
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func update(body []byte) {
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dupe := duplicate(config)
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if err := unmarshal(body, dupe); err != nil {
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log.Println("Failed to update config")
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return
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}
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config = dupe
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}
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func isStructPtr(target interface{}) bool {
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if val := reflect.ValueOf(target); val.Kind() == reflect.Ptr {
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if val = reflect.Indirect(val); val.Kind() == reflect.Struct {
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return true
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}
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}
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return false
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}
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func unmarshal(body []byte, target interface{}) error {
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if err := json.Unmarshal(body, target); err != nil {
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return err
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}
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return nil
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}
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func duplicate(original interface{}) interface{} {
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// Get the interface value
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val := reflect.ValueOf(original)
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// We expect a pointer to a struct, so now we need the underlying staruct
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val = reflect.Indirect(val)
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// Now we need the type (name) of this struct
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typ := val.Type()
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// Creating a duplicate instance of that struct
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dupe := reflect.New(typ).Interface()
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return dupe
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}
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