Unify error handling and HTTP statuses

Signed-off-by: Sean Du <do4suki@gmail.com>

internal/middleware/recovery.go

@@ -0,0 +1,40 @@
+package middleware
+
+import (
+	"honoka-chan/internal/session"
+	honokautils "honoka-chan/internal/utils"
+	"log"
+	"net/http"
+	"runtime/debug"
+
+	"github.com/gin-gonic/gin"
+)
+
+func Recovery() gin.HandlerFunc {
+	return func(ctx *gin.Context) {
+		defer func() {
+			recovered := recover()
+			if recovered == nil {
+				return
+			}
+
+			stack := debug.Stack()
+			log.Printf("panic serving %s %s: %v\n%s", ctx.Request.Method, ctx.Request.URL.String(), recovered, stack)
+
+			if !honokautils.IsMainPHPRequest(ctx.Request.URL.Path) {
+				ctx.AbortWithStatus(http.StatusInternalServerError)
+				return
+			}
+
+			content := honokautils.NewPanicContent(recovered, stack)
+			if value, ok := ctx.Get("session"); ok {
+				value.(*session.Session).AbortWithStatus(http.StatusInternalServerError, content)
+				return
+			}
+
+			honokautils.AbortMaintenanceJSON(ctx, http.StatusInternalServerError, content)
+		}()
+
+		ctx.Next()
+	}
+}