Add server stats (#15)

3. **Server Stats**: Shows real-time statistics about server usage:
   - Server Uptime
   - Download/Upload Counts (since start and last 24 hours)
   - HTTP Error Counts
   - Rate Limit Hit Count

4. **Rate Limit Stats**: Provides information about rate limiting, if applicable.

README.md

@@ -22,6 +22,35 @@ This project provides a simple HTTP server that offers ephemeral storage for IoT
 - Data is stored for a configurable duration before being deleted.
 - The server can be run on a local network or in the cloud.
 
+## Self-Hosted Info Website
+
+The iot-ephemeral-value-store server includes a self-hosted info website that provides valuable information about the server's status, usage, and API. This website is automatically available when you run the server and can be accessed at the root URL (e.g., `http://127.0.0.1:8088/`).
+
+### Features of the Info Website
+
+1. **Getting Started Guide**: Provides example URLs for uploading, downloading, and deleting data, customized with a generated key pair for immediate use.
+
+2. **Server Settings**: Displays important server configuration information, including:
+   - Software Version
+   - Software Build Time
+   - Data Retention Period
+
+3. **Server Stats**: Shows real-time statistics about server usage:
+   - Server Uptime
+   - Download/Upload Counts (since start and last 24 hours)
+   - HTTP Error Counts
+   - Rate Limit Hit Count
+
+4. **Rate Limit Stats**: Provides information about rate limiting, if applicable.
+
+5. **API Usage Guide**: Offers a quick reference for using the server's API, including:
+   - Creating Key Pairs
+   - Uploading Data
+   - Downloading Data (JSON and Plain Text)
+   - Advanced Patch Usage
+
+This self-hosted info website serves as a dashboard and quick-start guide, making it easier for users to understand and interact with the iot-ephemeral-value-store server.
+
 ## Diagrams
 
 ### Simple

httphandler/config.go

@@ -5,11 +5,13 @@ import (
 	"html"
 	"net/http"
 
+	"github.com/dhcgn/iot-ephemeral-value-store/stats"
 	"github.com/dhcgn/iot-ephemeral-value-store/storage"
 )
 
 type Config struct {
 	StorageInstance storage.Storage
+	StatsInstance   *stats.Stats
 }
 
 func sanitizeInput(input string) string {

httphandler/deleteHandler.go

@@ -13,6 +13,7 @@ func (c Config) DeleteHandler(w http.ResponseWriter, r *http.Request) {
 
 	downloadKey, err := domain.DeriveDownloadKey(uploadKey)
 	if err != nil {
+		c.StatsInstance.IncrementHTTPErrors()
 		http.Error(w, "Error deriving download key", http.StatusInternalServerError)
 		return
 	}

httphandler/downloadHandler.go

@@ -16,13 +16,15 @@ func (c Config) PlainDownloadHandler(w http.ResponseWriter, r *http.Request) {
 
 	jsonData, err := c.StorageInstance.GetJSON(downloadKey)
 	if err != nil {
+		c.StatsInstance.IncrementHTTPErrors()
 		http.Error(w, "Invalid download key or database error", http.StatusNotFound)
 		return
 	}
 
 	// Parse the JSON data to retrieve the specific parameter
 	paramMap := make(map[string]interface{})
 	if err := json.Unmarshal(jsonData, &paramMap); err != nil {
+		c.StatsInstance.IncrementHTTPErrors()
 		http.Error(w, "Error decoding JSON", http.StatusInternalServerError)
 		return
 	}
@@ -36,15 +38,19 @@ func (c Config) PlainDownloadHandler(w http.ResponseWriter, r *http.Request) {
 		if m, ok := value.(map[string]interface{}); ok {
 			value, ok = m[key]
 			if !ok {
+				c.StatsInstance.IncrementHTTPErrors()
 				http.Error(w, "Parameter not found", http.StatusNotFound)
 				return
 			}
 		} else {
+			c.StatsInstance.IncrementHTTPErrors()
 			http.Error(w, "Invalid parameter path", http.StatusBadRequest)
 			return
 		}
 	}
 
+	c.StatsInstance.IncrementDownloads()
+
 	// Return the value as plain text
 	w.Header().Set("Content-Type", "text/plain")
 	fmt.Fprintln(w, value)
@@ -56,10 +62,13 @@ func (c Config) DownloadHandler(w http.ResponseWriter, r *http.Request) {
 
 	jsonData, err := c.StorageInstance.GetJSON(downloadKey)
 	if err != nil {
+		c.StatsInstance.IncrementHTTPErrors()
 		http.Error(w, "Invalid download key or database error", http.StatusNotFound)
 		return
 	}
 
+	c.StatsInstance.IncrementDownloads()
+
 	// Set header and write the JSON data to the response writer
 	w.Header().Set("Content-Type", "application/json")
 	w.Write(jsonData)

httphandler/keyPairHandler.go

@@ -10,6 +10,7 @@ func (c Config) KeyPairHandler(w http.ResponseWriter, r *http.Request) {
 	uploadKey := domain.GenerateRandomKey()
 	downloadKey, err := domain.DeriveDownloadKey(uploadKey)
 	if err != nil {
+		c.StatsInstance.IncrementHTTPErrors()
 		http.Error(w, "Error deriving download key", http.StatusInternalServerError)
 		return
 	}

httphandler/uploadHandler.go

@@ -33,6 +33,7 @@ func (c Config) handleUpload(w http.ResponseWriter, r *http.Request, uploadKey,
 	// Derive download key
 	downloadKey, err := domain.DeriveDownloadKey(uploadKey)
 	if err != nil {
+		c.StatsInstance.IncrementHTTPErrors()
 		http.Error(w, "Error deriving download key", http.StatusInternalServerError)
 		return
 	}
@@ -51,6 +52,8 @@ func (c Config) handleUpload(w http.ResponseWriter, r *http.Request, uploadKey,
 	}
 	c.StorageInstance.Store(downloadKey, data)
 
+	c.StatsInstance.IncrementUploads()
+
 	// Construct and return response
 	constructAndReturnResponse(w, r, downloadKey, paramMap)
 }

main.go

@@ -11,19 +11,19 @@ import (
 	"text/template"
 	"time"
 
-	"github.com/dgraph-io/badger/v3"
 	"github.com/dhcgn/iot-ephemeral-value-store/domain"
 	"github.com/dhcgn/iot-ephemeral-value-store/httphandler"
 	"github.com/dhcgn/iot-ephemeral-value-store/middleware"
+	"github.com/dhcgn/iot-ephemeral-value-store/stats"
 	"github.com/dhcgn/iot-ephemeral-value-store/storage"
 	"github.com/gorilla/mux"
 )
 
 const (
 	// Server configuration
 	MaxRequestSize     = 1024 * 10 // 10 KB for request size limit
-	RateLimitPerSecond = 10        // Requests per second
-	RateLimitBurst     = 5         // Burst capability
+	RateLimitPerSecond = 100       // Requests per second
+	RateLimitBurst     = 10        // Burst capability
 
 	// Database and server paths
 	DefaultStorePath       = "./data"
@@ -44,7 +44,6 @@ var (
 	persistDurationString string
 	storePath             string
 	port                  int
-	db                    *badger.DB
 )
 
 // Set in build time
@@ -70,20 +69,24 @@ func main() {
 		log.Fatalf("Failed to parse duration: %v", err)
 	}
 
+	stats := stats.NewStats()
+
 	storage := storage.NewPersistentStorage(storePath, persistDuration)
 	defer storage.Db.Close()
 
 	httphandlerConfig := httphandler.Config{
 		StorageInstance: storage,
+		StatsInstance:   stats,
 	}
 
 	middlewareConfig := middleware.Config{
 		RateLimitPerSecond: RateLimitPerSecond,
 		RateLimitBurst:     RateLimitBurst,
 		MaxRequestSize:     MaxRequestSize,
+		StatsInstance:      stats,
 	}
 
-	r := createRouter(httphandlerConfig, middlewareConfig)
+	r := createRouter(httphandlerConfig, middlewareConfig, stats)
 
 	serverAddress := fmt.Sprintf("127.0.0.1:%d", port)
 	srv := &http.Server{
@@ -99,7 +102,7 @@ func main() {
 	}
 }
 
-func createRouter(hhc httphandler.Config, mc middleware.Config) *mux.Router {
+func createRouter(hhc httphandler.Config, mc middleware.Config, stats *stats.Stats) *mux.Router {
 	// Template parsing
 	tmpl, err := template.ParseFS(staticFiles, "static/index.html")
 	if err != nil {
@@ -134,7 +137,22 @@ func createRouter(hhc httphandler.Config, mc middleware.Config) *mux.Router {
 	r.HandleFunc("/delete/{uploadKey}", hhc.DeleteHandler).Methods("GET")
 	r.HandleFunc("/delete/{uploadKey}/", hhc.DeleteHandler).Methods("GET")
 
-	r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+	r.HandleFunc("/", templateHandler(tmpl, stats))
+
+	// Not Found handler
+	r.NotFoundHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		w.Write([]byte("404 Not Found"))
+	})
+
+	staticSubFS, _ := fs.Sub(staticFiles, "static")
+	r.PathPrefix("/").Handler(http.FileServer(http.FS(staticSubFS)))
+
+	return r
+}
+
+func templateHandler(tmpl *template.Template, stats *stats.Stats) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
 		key := domain.GenerateRandomKey()
 		key_down, err := domain.DeriveDownloadKey(key)
 		if err != nil {
@@ -147,20 +165,13 @@ func createRouter(hhc httphandler.Config, mc middleware.Config) *mux.Router {
 			DataRetention: persistDurationString,
 			Version:       Version,
 			BuildTime:     BuildTime,
-		}
-		tmpl.Execute(w, data)
-	})
 
-	// Not Found handler
-	r.NotFoundHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(http.StatusNotFound)
-		w.Write([]byte("404 Not Found"))
-	})
+			Uptime: stats.GetUptime(),
 
-	staticSubFS, _ := fs.Sub(staticFiles, "static")
-	r.PathPrefix("/").Handler(http.FileServer(http.FS(staticSubFS)))
-
-	return r
+			StateData: stats.GetCurrentStats(),
+		}
+		tmpl.Execute(w, data)
+	}
 }
 
 type PageData struct {
@@ -169,4 +180,8 @@ type PageData struct {
 	DataRetention string
 	Version       string
 	BuildTime     string
+
+	Uptime time.Duration
+
+	StateData stats.StatsData
 }