Backup database if a migration is needed (#415)

* Confirm before migrating database

Co-authored-by: WithoutPants <53250216+WithoutPants@users.noreply.github.com>

pkg/api/migrate.go

@@ -0,0 +1,66 @@
+package api
+
+import (
+	"fmt"
+	"html/template"
+	"net/http"
+
+	"github.com/stashapp/stash/pkg/database"
+)
+
+type migrateData struct {
+	ExistingVersion uint
+	MigrateVersion  uint
+	BackupPath      string
+}
+
+func getMigrateData() migrateData {
+	return migrateData{
+		ExistingVersion: database.Version(),
+		MigrateVersion:  database.AppSchemaVersion(),
+		BackupPath:      database.DatabaseBackupPath(),
+	}
+}
+
+func getMigrateHandler(w http.ResponseWriter, r *http.Request) {
+	if !database.NeedsMigration() {
+		http.Redirect(w, r, "/", 301)
+		return
+	}
+
+	data, _ := setupUIBox.Find("migrate.html")
+	templ, err := template.New("Migrate").Parse(string(data))
+	if err != nil {
+		http.Error(w, fmt.Sprintf("error: %s", err), 500)
+		return
+	}
+
+	err = templ.Execute(w, getMigrateData())
+	if err != nil {
+		http.Error(w, fmt.Sprintf("error: %s", err), 500)
+	}
+}
+
+func doMigrateHandler(w http.ResponseWriter, r *http.Request) {
+	err := r.ParseForm()
+	if err != nil {
+		http.Error(w, fmt.Sprintf("error: %s", err), 500)
+	}
+
+	backupPath := r.Form.Get("backuppath")
+
+	// perform database backup
+	if backupPath != "" {
+		if err = database.Backup(backupPath); err != nil {
+			http.Error(w, fmt.Sprintf("error backing up database: %s", err), 500)
+			return
+		}
+	}
+
+	err = database.RunMigrations()
+	if err != nil {
+		http.Error(w, fmt.Sprintf("error performing migration: %s", err), 500)
+		return
+	}
+	http.Redirect(w, r, "/", 301)
+}

pkg/api/server.go

@@ -20,6 +20,7 @@ import (
 	"github.com/gobuffalo/packr/v2"
 	"github.com/gorilla/websocket"
 	"github.com/rs/cors"
+	"github.com/stashapp/stash/pkg/database"
 	"github.com/stashapp/stash/pkg/logger"
 	"github.com/stashapp/stash/pkg/manager"
 	"github.com/stashapp/stash/pkg/manager/config"
@@ -83,6 +84,7 @@ func Start() {
 	r.Use(cors.AllowAll().Handler)
 	r.Use(BaseURLMiddleware)
 	r.Use(ConfigCheckMiddleware)
+	r.Use(DatabaseCheckMiddleware)
 
 	recoverFunc := handler.RecoverFunc(func(ctx context.Context, err interface{}) error {
 		logger.Error(err)
@@ -127,6 +129,10 @@ func Start() {
 		http.ServeFile(w, r, fn)
 	})
 
+	// Serve the migration UI
+	r.Get("/migrate", getMigrateHandler)
+	r.Post("/migrate", doMigrateHandler)
+
 	// Serve the setup UI
 	r.HandleFunc("/setup*", func(w http.ResponseWriter, r *http.Request) {
 		ext := path.Ext(r.URL.Path)
@@ -323,3 +329,17 @@ func ConfigCheckMiddleware(next http.Handler) http.Handler {
 		next.ServeHTTP(w, r)
 	})
 }
+
+func DatabaseCheckMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ext := path.Ext(r.URL.Path)
+		shouldRedirect := ext == "" && r.Method == "GET"
+		if shouldRedirect && database.NeedsMigration() {
+			if !strings.HasPrefix(r.URL.Path, "/migrate") {
+				http.Redirect(w, r, "/migrate", 301)
+				return
+			}
+		}
+		next.ServeHTTP(w, r)
+	})
+}