41 lines
733 B
Go
41 lines
733 B
Go
package handler
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import (
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"encoding/json"
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"fmt"
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"github.com/imkira/go-observer"
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"net/http"
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"strconv"
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)
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type Value struct {
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VersionRef int `json:"version"`
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}
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func SyncFactory(obs observer.Property) HandlerFunc {
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return func(w http.ResponseWriter, r *http.Request) {
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versionRef, err := strconv.Atoi(r.URL.Query().Get("v"))
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if err != nil {
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versionRef = -1
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}
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stream := obs.Observe()
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var value Value
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for {
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value = stream.Value().(Value)
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if value.VersionRef >= versionRef {
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break
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}
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select {
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case <-stream.Changes():
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stream.Next()
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}
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}
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jsonString, _ := json.MarshalIndent(value, "", " ")
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w.Header().Add("Content-Type", "application/json")
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fmt.Fprintf(w, string(jsonString))
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}
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}
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