enhc(server): allow adding multiple resource templates at once (#483)

* enhc(server): allow adding multiple resource templates at once

Following the same pattern from tools, prompts and resources, this patch allows
adding multiple resource templates at once.

* Apply coderabbitai suggestion

#483 (comment)

* Increase test coverage

Add a test case to cover the new function.

#483 (comment)

Author: rafaeljusto

mcptest/mcptest.go

@@ -23,7 +23,7 @@ type Server struct {
 	tools             []server.ServerTool
 	prompts           []server.ServerPrompt
 	resources         []server.ServerResource
-	resourceTemplates []ServerResourceTemplate
+	resourceTemplates []server.ServerResourceTemplate
 
 	cancel func()
 
@@ -107,22 +107,16 @@ func (s *Server) AddResources(resources ...server.ServerResource) {
 	s.resources = append(s.resources, resources...)
 }
 
-// ServerResourceTemplate combines a ResourceTemplate with its handler function.
-type ServerResourceTemplate struct {
-	Template mcp.ResourceTemplate
-	Handler  server.ResourceTemplateHandlerFunc
-}
-
 // AddResourceTemplate adds a resource template to an unstarted server.
 func (s *Server) AddResourceTemplate(template mcp.ResourceTemplate, handler server.ResourceTemplateHandlerFunc) {
-	s.resourceTemplates = append(s.resourceTemplates, ServerResourceTemplate{
+	s.resourceTemplates = append(s.resourceTemplates, server.ServerResourceTemplate{
 		Template: template,
 		Handler:  handler,
 	})
 }
 
 // AddResourceTemplates adds multiple resource templates to an unstarted server.
-func (s *Server) AddResourceTemplates(templates ...ServerResourceTemplate) {
+func (s *Server) AddResourceTemplates(templates ...server.ServerResourceTemplate) {
 	s.resourceTemplates = append(s.resourceTemplates, templates...)
 }
 
@@ -142,10 +136,7 @@ func (s *Server) Start(ctx context.Context) error {
 		mcpServer.AddTools(s.tools...)
 		mcpServer.AddPrompts(s.prompts...)
 		mcpServer.AddResources(s.resources...)
-		
-		for _, template := range s.resourceTemplates {
-			mcpServer.AddResourceTemplate(template.Template, template.Handler)
-		}
+		mcpServer.AddResourceTemplates(s.resourceTemplates...)
 
 		logger := log.New(&s.logBuffer, "", 0)
 

server/server.go

@@ -64,6 +64,12 @@ type ServerResource struct {
 	Handler  ResourceHandlerFunc
 }
 
+// ServerResourceTemplate combines a ResourceTemplate with its handler function.
+type ServerResourceTemplate struct {
+	Template mcp.ResourceTemplate
+	Handler  ResourceTemplateHandlerFunc
+}
+
 // serverKey is the context key for storing the server instance
 type serverKey struct{}
 
@@ -365,17 +371,16 @@ func (s *MCPServer) RemoveResource(uri string) {
 	}
 }
 
-// AddResourceTemplate registers a new resource template and its handler
-func (s *MCPServer) AddResourceTemplate(
-	template mcp.ResourceTemplate,
-	handler ResourceTemplateHandlerFunc,
-) {
+// AddResourceTemplates registers multiple resource templates at once
+func (s *MCPServer) AddResourceTemplates(resourceTemplates ...ServerResourceTemplate) {
 	s.implicitlyRegisterResourceCapabilities()
 
 	s.resourcesMu.Lock()
-	s.resourceTemplates[template.URITemplate.Raw()] = resourceTemplateEntry{
-		template: template,
-		handler:  handler,
+	for _, entry := range resourceTemplates {
+		s.resourceTemplates[entry.Template.URITemplate.Raw()] = resourceTemplateEntry{
+			template: entry.Template,
+			handler:  entry.Handler,
+		}
 	}
 	s.resourcesMu.Unlock()
 
@@ -386,6 +391,14 @@ func (s *MCPServer) AddResourceTemplate(
 	}
 }
 
+// AddResourceTemplate registers a new resource template and its handler
+func (s *MCPServer) AddResourceTemplate(
+	template mcp.ResourceTemplate,
+	handler ResourceTemplateHandlerFunc,
+) {
+	s.AddResourceTemplates(ServerResourceTemplate{Template: template, Handler: handler})
+}
+
 // AddPrompts registers multiple prompts at once
 func (s *MCPServer) AddPrompts(prompts ...ServerPrompt) {
 	s.implicitlyRegisterPromptCapabilities()

server/server_test.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"reflect"
+	"slices"
 	"sort"
 	"testing"
 	"time"
@@ -1456,6 +1457,54 @@ func TestMCPServer_ResourceTemplates(t *testing.T) {
 		assert.Equal(t, "text/plain", resultContent.MIMEType)
 		assert.Equal(t, "test content: something", resultContent.Text)
 	})
+
+	server.AddResourceTemplates(
+		ServerResourceTemplate{
+			Template: mcp.NewResourceTemplate(
+				"test://test-another-resource-1",
+				"Another Resource 1",
+			),
+			Handler: func(ctx context.Context, request mcp.ReadResourceRequest) ([]mcp.ResourceContents, error) {
+				return []mcp.ResourceContents{}, nil
+			},
+		},
+		ServerResourceTemplate{
+			Template: mcp.NewResourceTemplate(
+				"test://test-another-resource-2",
+				"Another Resource 2",
+			),
+			Handler: func(ctx context.Context, request mcp.ReadResourceRequest) ([]mcp.ResourceContents, error) {
+				return []mcp.ResourceContents{}, nil
+			},
+		},
+	)
+
+	t.Run("Check bulk add resource templates", func(t *testing.T) {
+		assert.Equal(t, 3, len(server.resourceTemplates))
+	})
+
+	t.Run("Get resource template again", func(t *testing.T) {
+		response := server.HandleMessage(
+			context.Background(),
+			[]byte(listMessage),
+		)
+		assert.NotNil(t, response)
+
+		resp, ok := response.(mcp.JSONRPCResponse)
+		assert.True(t, ok)
+		listResult, ok := resp.Result.(mcp.ListResourceTemplatesResult)
+		assert.True(t, ok)
+		assert.Len(t, listResult.ResourceTemplates, 3)
+
+		// resource templates are stored in a map, so the order is not guaranteed
+		for _, rt := range listResult.ResourceTemplates {
+			assert.True(t, slices.Contains([]string{
+				"My Resource",
+				"Another Resource 1",
+				"Another Resource 2",
+			}, rt.Name))
+		}
+	})
 }
 
 func createTestServer() *MCPServer {