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

internal/api/handlers/v0/health.go

@@ -0,0 +1,15 @@
+// Package v0 contains API handlers for version 0 of the API
+package v0
+
+import (
+	"encoding/json"
+	"net/http"
+)
+
+// HealthHandler returns a handler for health check endpoint
+func HealthHandler() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
+	}
+}

internal/api/handlers/v0/ping.go

@@ -0,0 +1,27 @@
+// Package v0 contains API handlers for version 0 of the API
+package v0
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/modelcontextprotocol/registry/internal/config"
+)
+
+// PingHandler returns a handler for the ping endpoint that returns build version
+func PingHandler(cfg *config.Config) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+
+		response := map[string]string{
+			"status":  "ok",
+			"version": cfg.Version,
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(response)
+	}
+}

internal/api/handlers/v0/servers.go

@@ -0,0 +1,125 @@
+// Package v0 contains API handlers for version 0 of the API
+package v0
+
+import (
+	"encoding/json"
+	"net/http"
+	"strconv"
+
+	"github.com/google/uuid"
+	"github.com/modelcontextprotocol/registry/internal/model"
+	"github.com/modelcontextprotocol/registry/internal/service"
+)
+
+// Response is a paginated API response
+type PaginatedResponse struct {
+	Data     []model.Entry `json:"servers"`
+	Metadata Metadata      `json:"metadata,omitempty"`
+}
+
+// Metadata contains pagination metadata
+type Metadata struct {
+	NextCursor string `json:"next_cursor,omitempty"`
+}
+
+// ServersHandler returns a handler for listing registry items
+func ServersHandler(registry service.RegistryService) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+
+		// Parse cursor and limit from query parameters
+		cursor := r.URL.Query().Get("cursor")
+		if cursor != "" {
+			_, err := uuid.Parse(cursor)
+			if err != nil {
+				http.Error(w, "Invalid cursor parameter", http.StatusBadRequest)
+				return
+			}
+		}
+		limitStr := r.URL.Query().Get("limit")
+
+		// Default limit if not specified
+		limit := 30
+
+		// Try to parse limit from query param
+		if limitStr != "" {
+			parsedLimit, err := strconv.Atoi(limitStr)
+			if err != nil {
+				http.Error(w, "Invalid limit parameter", http.StatusBadRequest)
+				return
+			}
+
+			// Check if limit is within reasonable bounds
+			if parsedLimit <= 0 {
+				http.Error(w, "Limit must be greater than 0", http.StatusBadRequest)
+				return
+			}
+
+			if parsedLimit > 100 {
+				// Cap maximum limit to prevent excessive queries
+				limit = 100
+			} else {
+				limit = parsedLimit
+			}
+		}
+
+		// Use the GetAll method to get paginated results
+		registries, nextCursor, err := registry.List(cursor, limit)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		// Create paginated response
+		response := PaginatedResponse{
+			Data: registries,
+		}
+
+		// Add metadata if there's a next cursor
+		if nextCursor != "" {
+			response.Metadata = Metadata{
+				NextCursor: nextCursor,
+			}
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(response)
+	}
+}
+
+// ServersDetailHandler returns a handler for getting details of a specific server by ID
+func ServersDetailHandler(registry service.RegistryService) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+
+		// Extract the server ID from the URL path
+		id := r.PathValue("id")
+
+		// Validate that the ID is a valid UUID
+		_, err := uuid.Parse(id)
+		if err != nil {
+			http.Error(w, "Invalid server ID format", http.StatusBadRequest)
+			return
+		}
+
+		// Get the server details from the registry service
+		serverDetail, err := registry.GetByID(id)
+		if err != nil {
+			if err.Error() == "record not found" {
+				http.Error(w, "Server not found", http.StatusNotFound)
+				return
+			}
+			http.Error(w, "Error retrieving server details", http.StatusInternalServerError)
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(serverDetail)
+	}
+}