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package main
import (
"fmt"
"log"
"net/http"
"strconv"
)
const addr = ":9090"
type HumidityHandler struct {
humidity Record[float32]
}
func newHumidityHandler() HumidityHandler {
return HumidityHandler{newRecord[float32]()}
}
func (h HumidityHandler) Close() {
h.humidity.Close()
}
func (h HumidityHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
log.Println(r.Method, r.URL)
switch r.Method {
case http.MethodGet:
h.get(w, r)
case http.MethodPost:
h.post(w, r)
default:
w.WriteHeader(http.StatusMethodNotAllowed)
fmt.Fprintf(w, "invalid method: '%s'", r.Method)
}
}
func (h HumidityHandler) get(w http.ResponseWriter, r *http.Request) {
c := make(chan float32)
h.humidity.getRecent <- c
humidity, ok := <-c
if !ok {
w.WriteHeader(http.StatusGone)
fmt.Fprintf(w, "no humidity data stored on server")
return
}
fmt.Fprintf(w, "%.2f", humidity)
}
func (h HumidityHandler) post(w http.ResponseWriter, r *http.Request) {
query := r.URL.RawQuery
humidity, err := strconv.ParseFloat(query, 32)
if err != nil {
w.WriteHeader(http.StatusBadRequest)
fmt.Fprintf(w, "invalid query string: '%s'", query)
return
}
h.humidity.put <- float32(humidity)
}
func main() {
humidityHandler := newHumidityHandler()
defer humidityHandler.Close()
http.Handle("/humidity", humidityHandler)
fmt.Printf("Listening on %s...\n", addr)
log.Fatal(http.ListenAndServe(addr, nil))
}
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