Init world. Basic registry API server

Work in progress .
This commit adds the core registry service implementation with methods to:
- Retrieve all registry entries
- List entries with cursor-based pagination
- Fetch specific server details by ID

cmd/registry/main.go

@@ -0,0 +1,101 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/modelcontextprotocol/registry/internal/api"
+	"github.com/modelcontextprotocol/registry/internal/config"
+	"github.com/modelcontextprotocol/registry/internal/database"
+	"github.com/modelcontextprotocol/registry/internal/service"
+)
+
+func main() {
+	// Parse command line flags
+	showVersion := flag.Bool("version", false, "Display version information")
+	flag.Parse()
+
+	// Show version information if requested
+	if *showVersion {
+		fmt.Printf("MCP Registry v%s\n", Version)
+		fmt.Printf("Git commit: %s\n", GitCommit)
+		fmt.Printf("Build time: %s\n", BuildTime)
+		return
+	}
+
+	log.Printf("Starting MCP Registry Application v%s (commit: %s)", Version, GitCommit)
+
+	// Initialize configuration
+	cfg := config.NewConfig()
+
+	// Initialize services based on environment
+	var registryService service.RegistryService
+
+	if cfg.Environment == "test" {
+		// Use fake registry service in test environment
+		registryService = service.NewFakeRegistryService()
+		log.Println("Using fake registry service with dummy data (test environment)")
+	} else {
+		// Use MongoDB for real registry service in production/other environments
+		// Create a context with timeout for MongoDB connection
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+
+		// Connect to MongoDB
+		mongoDB, err := database.NewMongoDB(ctx, cfg.DatabaseURL, cfg.DatabaseName, cfg.CollectionName)
+		if err != nil {
+			log.Fatalf("Failed to connect to MongoDB: %v", err)
+		}
+
+		// Create registry service with MongoDB
+		registryService = service.NewRegistryServiceWithDB(mongoDB)
+		log.Printf("Using MongoDB-based registry service (%s environment)", cfg.Environment)
+		log.Printf("MongoDB database name: %s", cfg.DatabaseName)
+		log.Printf("MongoDB collection name: %s", cfg.CollectionName)
+
+		// Store the MongoDB instance for later cleanup
+		defer func() {
+			if err := mongoDB.Close(); err != nil {
+				log.Printf("Error closing MongoDB connection: %v", err)
+			} else {
+				log.Println("MongoDB connection closed successfully")
+			}
+		}()
+	}
+
+	// Initialize HTTP server
+	server := api.NewServer(cfg, registryService)
+
+	// Start server in a goroutine so it doesn't block signal handling
+	go func() {
+		log.Printf("HTTP server listening on %s", cfg.ServerAddress)
+		if err := server.Start(); err != nil && err != http.ErrServerClosed {
+			log.Fatalf("Failed to start server: %v", err)
+		}
+	}()
+
+	// Wait for interrupt signal to gracefully shutdown the server
+	quit := make(chan os.Signal, 1)
+
+	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
+	<-quit
+	log.Println("Shutting down server...")
+
+	// Create context with timeout for shutdown
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	// Gracefully shutdown the server
+	if err := server.Shutdown(ctx); err != nil {
+		log.Fatalf("Server forced to shutdown: %v", err)
+	}
+
+	log.Println("Server exiting")
+}

cmd/registry/version.go

@@ -0,0 +1,13 @@
+package main
+
+// Version info for the MCP Registry application
+var (
+	// Version is the current version of the MCP Registry application
+	Version = "0.1.0"
+
+	// BuildTime is the time at which the binary was built
+	BuildTime = "undefined"
+
+	// GitCommit is the git commit that was compiled
+	GitCommit = "undefined"
+)