Generate HTTP endpoints for environment sensors

- Move update request sanity checks to new method in handlers/util.go
- Change EnvironmentSensor.Value type because ParseFloat returns float64

handlers/sensors.go

@@ -0,0 +1,39 @@
+package handlers
+
+import (
+	"io"
+	"log"
+	"math"
+	"net/http"
+	"strconv"
+	"time"
+
+	"gitlab.hamburg.ccc.de/ccchh/spaceapid/config"
+	"gitlab.hamburg.ccc.de/ccchh/spaceapid/types"
+)
+
+func EnvironmentSensor(
+	authDB config.HTTPBACredentials, validCredentials []config.HTTPBACredentialID,
+	resp *types.EnvironmentSensor,
+) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		body := updateEndpointValidator(authDB, validCredentials, w, r)
+
+		// Parse request body
+		newState, err := strconv.ParseFloat(string(body), 64)
+		if err != nil || math.IsInf(newState, 0) {
+			log.Println("Failed to parse request body from", r.RemoteAddr)
+			w.WriteHeader(http.StatusBadRequest)
+			_, _ = io.WriteString(w, "HTTP request body has to be a valid float64 value != +/-Inf")
+			return
+		}
+
+		// Set SpaceAPI response values
+		resp.Value = newState
+		resp.LastChange = time.Now().Unix()
+
+		// Respond with OK
+		w.WriteHeader(http.StatusOK)
+		_, _ = io.WriteString(w, "Update Successful")
+	}
+}