From 52743017a36b811014ff10f66cda94d3e7929f70 Mon Sep 17 00:00:00 2001
From: Steven <stevenlgtm@gmail.com>
Date: Fri, 15 Dec 2023 07:32:49 +0800
Subject: [PATCH] chore: implement memo route

---
 .gitignore                  |  1 +
 server/frontend/frontend.go | 57 ++++++++++++++++++++++++++++++++++---
 server/server.go            | 10 +++----
 3 files changed, 58 insertions(+), 10 deletions(-)

diff --git a/.gitignore b/.gitignore
index 9b988506..4a6159e4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,7 @@ tmp
 
 # Frontend asset
 web/dist
+server/frontend/dist
 
 # build folder
 build
diff --git a/server/frontend/frontend.go b/server/frontend/frontend.go
index d1e9b943..81eea94c 100644
--- a/server/frontend/frontend.go
+++ b/server/frontend/frontend.go
@@ -2,6 +2,7 @@ package frontend
 
 import (
 	"embed"
+	"fmt"
 	"io/fs"
 	"net/http"
 	"strings"
@@ -10,6 +11,8 @@ import (
 	"github.com/labstack/echo/v4/middleware"
 
 	"github.com/usememos/memos/internal/util"
+	"github.com/usememos/memos/server/profile"
+	"github.com/usememos/memos/store"
 )
 
 //go:embed dist
@@ -18,7 +21,19 @@ var embeddedFiles embed.FS
 //go:embed dist/index.html
 var rawIndexHTML string
 
-func Serve(e *echo.Echo) {
+type FrontendService struct {
+	Profile *profile.Profile
+	Store   *store.Store
+}
+
+func NewFrontendService(profile *profile.Profile, store *store.Store) *FrontendService {
+	return &FrontendService{
+		Profile: profile,
+		Store:   store,
+	}
+}
+
+func (s *FrontendService) Serve(e *echo.Echo) {
 	// Use echo static middleware to serve the built dist folder
 	// refer: https://github.com/labstack/echo/blob/master/middleware/static.go
 	e.Use(middleware.StaticWithConfig(middleware.StaticConfig{
@@ -44,16 +59,50 @@ func Serve(e *echo.Echo) {
 		Filesystem: getFileSystem("dist/assets"),
 	}))
 
-	registerRoutes(e)
+	s.registerRoutes(e)
 }
 
-func registerRoutes(e *echo.Echo) {
+func (s *FrontendService) registerRoutes(e *echo.Echo) {
 	e.GET("/m/:memoID", func(c echo.Context) error {
-		indexHTML := strings.ReplaceAll(rawIndexHTML, "<!-- memos.metadata -->", "<meta name=\"memos-memo-id\" content=\""+c.Param("memoID")+"\">"+"\n")
+		ctx := c.Request().Context()
+		memoID, err := util.ConvertStringToInt32(c.Param("memoID"))
+		if err != nil {
+			return echo.NewHTTPError(http.StatusBadRequest, "invalid memo id")
+		}
+
+		memo, err := s.Store.GetMemo(ctx, &store.FindMemo{
+			ID: &memoID,
+		})
+		if err != nil {
+			return echo.NewHTTPError(http.StatusInternalServerError, "failed to retrieve memo")
+		}
+		if memo == nil {
+			return echo.NewHTTPError(http.StatusNotFound, "memo not found")
+		}
+		if memo.Visibility != store.Public {
+			return echo.NewHTTPError(http.StatusForbidden, "memo is not public")
+		}
+		indexHTML := strings.ReplaceAll(rawIndexHTML, "<!-- memos.metadata -->", generateMemoMetadata(memo))
 		return c.HTML(http.StatusOK, indexHTML)
 	})
 }
 
+func generateMemoMetadata(memo *store.Memo) string {
+	metadataList := []string{
+		fmt.Sprintf(`<meta name="description" content="%s" />`, memo.Content),
+		fmt.Sprintf(`<meta property="og:title" content="%s" />`, fmt.Sprintf("Memos - %d", memo.ID)),
+		fmt.Sprintf(`<meta property="og:description" content="%s" />`, memo.Content),
+		fmt.Sprintf(`<meta property="og:image" content="%s" />`, "https://www.usememos.com/logo.png"),
+		`<meta property="og:type" content="website" />`,
+		// Twitter related metadata.
+		fmt.Sprintf(`<meta name="twitter:title" content="%s" />`, fmt.Sprintf("Memos - %d", memo.ID)),
+		fmt.Sprintf(`<meta name="twitter:description" content="%s" />`, memo.Content),
+		fmt.Sprintf(`<meta name="twitter:image" content="%s" />`, "https://www.usememos.com/logo.png"),
+		`<meta name="twitter:card" content="summary" />`,
+	}
+	return strings.Join(metadataList, "\n")
+}
+
 func getFileSystem(path string) http.FileSystem {
 	fs, err := fs.Sub(embeddedFiles, path)
 	if err != nil {
diff --git a/server/server.go b/server/server.go
index 93585fae..aed33630 100644
--- a/server/server.go
+++ b/server/server.go
@@ -33,9 +33,6 @@ type Server struct {
 	Profile *profile.Profile
 	Store   *store.Store
 
-	// API services.
-	apiV2Service *apiv2.APIV2Service
-
 	// Asynchronous runners.
 	backupRunner *backup.BackupRunner
 	telegramBot  *telegram.Bot
@@ -84,7 +81,8 @@ func NewServer(ctx context.Context, profile *profile.Profile, store *store.Store
 	s.ID = serverID
 
 	// Serve frontend.
-	frontend.Serve(e)
+	frontendService := frontend.NewFrontendService(profile, store)
+	frontendService.Serve(e)
 
 	// Serve swagger in dev/demo mode.
 	if profile.Mode == "dev" || profile.Mode == "demo" {
@@ -110,9 +108,9 @@ func NewServer(ctx context.Context, profile *profile.Profile, store *store.Store
 	apiV1Service := apiv1.NewAPIV1Service(s.Secret, profile, store, s.telegramBot)
 	apiV1Service.Register(rootGroup)
 
-	s.apiV2Service = apiv2.NewAPIV2Service(s.Secret, profile, store, s.Profile.Port+1)
+	apiV2Service := apiv2.NewAPIV2Service(s.Secret, profile, store, s.Profile.Port+1)
 	// Register gRPC gateway as api v2.
-	if err := s.apiV2Service.RegisterGateway(ctx, e); err != nil {
+	if err := apiV2Service.RegisterGateway(ctx, e); err != nil {
 		return nil, errors.Wrap(err, "failed to register gRPC gateway")
 	}