nau-sidewalks/main.go

package main

import (
	"embed"
	"encoding/json"
	"flag"
	"fmt"
	"io/fs"
	"log"
	"math/rand/v2"
	"net/http"
	"runtime/debug"
	"strconv"
	"time"

	"git.chandlerswift.com/chandlerswift/nau-sidewalks/sidewalk"
)

//go:embed static
var embeddedFiles embed.FS

//go:embed data/sidewalks.json
var sidewalk_data []byte

var buildInfoJSON []byte

const DEVEL = false // serve files from dev dir, not embedded, so I don't have to rebuild the app every time

func main() {
	port := flag.Int("port", 8000, "Port to listen on")
	flag.Parse()

	if DEVEL {
		http.Handle("GET /", http.FileServer(http.Dir("./static")))
	} else {
		frontend, err := fs.Sub(embeddedFiles, "static")
		if err != nil {
			panic(err)
		}
		http.Handle("GET /", http.FileServer(http.FS(frontend)))
	}

	// Decode the JSON data
	var sidewalks []sidewalk.Sidewalk
	if err := json.Unmarshal(sidewalk_data, &sidewalks); err != nil {
		log.Fatalf("Error decoding JSON: %v", err)
	}

	for i := range sidewalks {
		sidewalks[i].Condition = sidewalk.Condition(rand.IntN(4))
	}

	initializeBuildInfoJSON()
	http.HandleFunc("GET /api/version", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		w.Write(buildInfoJSON)
	})

	http.HandleFunc("GET /api/sidewalks", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(sidewalks)
	})

	http.HandleFunc("POST /api/sidewalks/{id}", func(w http.ResponseWriter, r *http.Request) {
		err := r.ParseForm()
		if err != nil {
			http.Error(w, "Could not parse form", http.StatusInternalServerError)
		}
		sidewalkID, err := strconv.Atoi(r.PathValue("id"))
		if err != nil {
			http.Error(w, "Invalid id", http.StatusBadRequest)
			return
		}
		condition, err := strconv.Atoi(r.Form.Get("condition"))
		if err != nil {
			http.Error(w, "Invalid condition", http.StatusBadRequest)
		}
		sidewalks[sidewalkID].Condition = sidewalk.Condition(condition)
		sidewalks[sidewalkID].LastUpdated = time.Now()
		http.Redirect(w, r, "/", http.StatusSeeOther)
	})

	fmt.Printf("Serving on :%v\n", *port)
	panic(http.ListenAndServe(fmt.Sprintf(":%v", *port), nil))
}

func initializeBuildInfoJSON() {
	rawBuildInfo, _ := debug.ReadBuildInfo()
	var revision, time string
	var dirty bool
	for _, buildSetting := range rawBuildInfo.Settings {
		if buildSetting.Key == "vcs.revision" {
			revision = buildSetting.Value
		} else if buildSetting.Key == "vcs.time" {
			time = buildSetting.Value
		} else if buildSetting.Key == "vcs.modified" {
			dirty = buildSetting.Value == "true"
		}
	}
	buildInfo := map[string]interface{}{
		"GitRev":       revision,
		"GitDirty":     dirty,
		"GitTime":      time,
		"GoVersion":    rawBuildInfo.GoVersion,
		"AllBuildInfo": rawBuildInfo.String(),
	}

	var err error
	buildInfoJSON, err = json.Marshal(buildInfo)
	if err != nil {
		panic(err)
	}
}