feat: add lastfm route and workers

.env.example

@@ -1,2 +1,6 @@
 # Port for the server
 PORT=8888
+# Your last.fm username
+LASTFM_USERNAME="axolotlmaid"
+# API Key for last.fm
+LASTFM_API_KEY="API_KEY_GOES_HERE"

cmd/backend/main.go

@@ -8,6 +8,7 @@ import (
 	"github.com/lmittmann/tint"
 
 	"backend/internal/server"
+	"backend/internal/worker"
 )
 
 func main() {
@@ -19,5 +20,6 @@ func main() {
 		slog.Error("Error loading .env file", slog.Any("error", err))
 	}
 
+	go worker.StartWorkers()
 	server.NewRouter()
 }

internal/handler/lastfm.go

@@ -0,0 +1,12 @@
+package handler
+
+import (
+	"backend/internal/worker"
+	"encoding/json"
+	"net/http"
+)
+
+func HandleGetCurrentlyPlaying(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(worker.LastFMData)
+}

internal/model/lastfm.go

@@ -0,0 +1,27 @@
+package model
+
+type LastFMAPI struct {
+	RecentTracks struct {
+		TrackList []struct {
+			Artist struct {
+				Text string `json:"#text"`
+			} `json:"artist"`
+			Name  string `json:"name"`
+			Image []struct {
+				Text string `json:"#text"`
+			} `json:"image"`
+			Url        string `json:"url"`
+			Attributes *struct {
+				NowPlaying string `json:"nowplaying"`
+			} `json:"@attr,omitempty"`
+		} `json:"track"`
+	} `json:"recenttracks"`
+}
+
+type LastFMData struct {
+	Song    string `json:"song"`
+	Artist  string `json:"artist"`
+	Image   string `json:"image"`
+	Url     string `json:"url"`
+	Playing bool   `json:"playing"`
+}

internal/server/router.go

@@ -29,6 +29,8 @@ func NewRouter() {
 	r.Get("/visitor-counter", handler.HandleGetVisitorCounter)
 	r.Patch("/visitor-counter", handler.HandlePatchVisitorCounter)
 
+	r.Get("/currently-playing", handler.HandleGetCurrentlyPlaying)
+
 	slog.Info("Starting server", slog.Any("port", os.Getenv("PORT")))
 	http.ListenAndServe(":"+os.Getenv("PORT"), r)
 }

internal/service/lastfm.go

@@ -0,0 +1,55 @@
+package service
+
+import (
+	"backend/internal/model"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log/slog"
+	"net/http"
+	"os"
+)
+
+func GetLastFMData() model.LastFMData {
+	data := model.LastFMData{
+		Song:    "api error",
+		Artist:  "???",
+		Image:   "/missing.webp",
+		Url:     "https://www.last.fm/user/axolotlmaid" + os.Getenv("LASTFM_USERNAME"),
+		Playing: false,
+	}
+
+	url := fmt.Sprintf("http://ws.audioscrobbler.com/2.0/?method=user.getrecenttracks&user=%s&api_key=%s&format=json&limit=1", os.Getenv("LASTFM_USERNAME"), os.Getenv("LASTFM_API_KEY"))
+	res, err := http.Get(url)
+	if err != nil {
+		slog.Error("Error requesting last.fm API", slog.Any("error", err))
+		return data
+	}
+
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		slog.Error("Error reading body", slog.Any("error", err))
+		return data
+	}
+
+	var lastfmJSON model.LastFMAPI
+
+	err = json.Unmarshal(body, &lastfmJSON)
+	if err != nil {
+		slog.Error("Error unmarshalling JSON", slog.Any("error", err))
+		return data
+	}
+
+	lastfmData := lastfmJSON.RecentTracks.TrackList[0]
+
+	if lastfmData.Attributes != nil {
+		data.Playing = true
+	}
+
+	data.Song = lastfmData.Name
+	data.Artist = lastfmData.Artist.Text
+	data.Image = lastfmData.Image[2].Text
+	data.Url = lastfmData.Url
+
+	return data
+}

internal/worker/lastfm.go

@@ -0,0 +1,20 @@
+package worker
+
+import (
+	"backend/internal/model"
+	"backend/internal/service"
+	"log/slog"
+	"time"
+)
+
+var LastFMData model.LastFMData
+
+func StartLastFMWorker() {
+	slog.Info("Starting last.fm worker...")
+	LastFMData = service.GetLastFMData()
+
+	for range time.Tick(30 * time.Second) {
+		slog.Info("Requesting last.fm...")
+		LastFMData = service.GetLastFMData()
+	}
+}

internal/worker/worker.go

@@ -0,0 +1,5 @@
+package worker
+
+func StartWorkers() {
+	go StartLastFMWorker()
+}