Add structured logging to documentStore methods

To troubleshoot reported issues, we add more debugging outputs in
the logging. This includes detailed, structured logs in the Create
and FindID methods to provide better traceability and debuggability.

These changes help diagnose issues by providing detailed context in
the logs, which should improve the ability to identify and resolve
problems.

See also: #9

main.go

@@ -7,6 +7,7 @@ import (
 	"excalidraw-complete/handlers/api/documents"
 	"excalidraw-complete/handlers/api/firebase"
 	"excalidraw-complete/stores"
+	"flag"
 	"fmt"
 	"io"
 	"io/fs"
@@ -16,6 +17,8 @@ import (
 	"strings"
 	"syscall"
 
+	"github.com/sirupsen/logrus"
+
 	"github.com/go-chi/chi/v5"
 	"github.com/go-chi/chi/v5/middleware"
 	"github.com/go-chi/cors"
@@ -239,6 +242,18 @@ func waitForShutdown(ioo *socketio.Server) {
 }
 
 func main() {
+	// Define a log level flag
+	logLevel := flag.String("loglevel", "info", "Set the logging level: debug, info, warn, error, fatal, panic")
+	flag.Parse()
+
+	// Set the log level
+	level, err := logrus.ParseLevel(*logLevel)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Invalid log level: %v\n", err)
+		os.Exit(1)
+	}
+	logrus.SetLevel(level)
+
 	documentStore := stores.GetStore() // Make sure this is well-defined in your "stores" package
 	r := setupRouter(documentStore)
 	ioo := setupSocketIO()
@@ -251,8 +266,15 @@ func main() {
 	})
 	r.Mount("/", handleUI())
 
-	go http.ListenAndServe(":3002", r)
-	fmt.Println("listen on 3002")
+	addr := ":3002"
+	logrus.WithField("addr", addr).Info("starting server")
+	go func() {
+		if err := http.ListenAndServe(addr, r); err != nil {
+			logrus.WithField("event", "start server").Fatal(err)
+		}
+	}()
+
+	logrus.Debug("Server is running in the background")
 	waitForShutdown(ioo)
 
 }