refactored for maintainability

internal/handlers/register.go

@@ -3,7 +3,6 @@ package handlers
 import (
 	"context"
 	"net/http"
-	"time"
 
 	"git.haelnorr.com/h/golib/cookies"
 	"git.haelnorr.com/h/golib/hws"
@@ -14,6 +13,7 @@ import (
 	"git.haelnorr.com/h/oslstats/internal/config"
 	"git.haelnorr.com/h/oslstats/internal/db"
 	"git.haelnorr.com/h/oslstats/internal/store"
+	"git.haelnorr.com/h/oslstats/internal/throw"
 	"git.haelnorr.com/h/oslstats/internal/view/page"
 )
 
@@ -29,27 +29,9 @@ func Register(
 			attempts, exceeded, track := store.TrackRedirect(r, "/register", 3)
 
 			if exceeded {
-				err := errors.Errorf(
-					"registration redirect loop detected after %d attempts | ip=%s ua=%s path=%s first_seen=%s ssl=%t",
-					attempts,
-					track.IP,
-					track.UserAgent,
-					track.Path,
-					track.FirstSeen.Format("2006-01-02T15:04:05Z07:00"),
-					cfg.HWSAuth.SSL,
-				)
-
+				err := track.Error(attempts)
 				store.ClearRedirectTrack(r, "/register")
-
-				throwError(
-					s,
-					w,
-					r,
-					http.StatusBadRequest,
-					"Registration failed: Cookies appear to be blocked or disabled. Please enable cookies in your browser and try again. If this problem persists, try a different browser or contact support.",
-					err,
-					"warn",
-				)
+				throw.BadRequest(s, w, r, "Cookies appear to be blocked or disabled. Please enable cookies in your browser and try again", err)
 				return
 			}
 
@@ -65,68 +47,45 @@ func Register(
 			}
 
 			store.ClearRedirectTrack(r, "/register")
-			ctx, cancel := context.WithTimeout(r.Context(), 10*time.Second)
-			defer cancel()
-			tx, err := conn.BeginTx(ctx, nil)
-			if err != nil {
-				throwInternalServiceError(s, w, r, "Database transaction failed", err)
-				return
-			}
-			defer tx.Rollback()
-			method := r.Method
-			if method == "GET" {
-				tx.Commit()
+
+			if r.Method == "GET" {
 				renderSafely(page.Register(details.DiscordUser.Username), s, r, w)
 				return
 			}
-			if method == "POST" {
-				username := r.FormValue("username")
-				user, err := registerUser(ctx, tx, username, details)
+			username := r.FormValue("username")
+			unique := false
+			var user *db.User
+			if ok := db.WithNotifyTx(s, w, r, conn, func(ctx context.Context, tx bun.Tx) (bool, error) {
+				unique, err = db.IsUnique(ctx, tx, (*db.User)(nil), "username", username)
 				if err != nil {
-					err = notifyInternalServiceError(s, r, "Registration failed", err)
-					if err != nil {
-						throwInternalServiceError(s, w, r, "Registration failed", err)
-					}
+					return false, errors.Wrap(err, "db.IsUsernameUnique")
+				}
+				if !unique {
+					return true, nil
+				}
+				user, err = db.CreateUser(ctx, tx, username, details.DiscordUser)
+				if err != nil {
+					return false, errors.Wrap(err, "db.CreateUser")
+				}
+				err = user.UpdateDiscordToken(ctx, tx, details.Token)
+				if err != nil {
+					return false, errors.Wrap(err, "db.UpdateDiscordToken")
+				}
+				return true, nil
+			}); !ok {
+				return
+			}
+			if !unique {
+				w.WriteHeader(http.StatusConflict)
+			} else {
+				err = auth.Login(w, r, user, true)
+				if err != nil {
+					throw.InternalServiceError(s, w, r, "Login failed", err)
 					return
 				}
-				tx.Commit()
-				if user == nil {
-					w.WriteHeader(http.StatusConflict)
-				} else {
-					err = auth.Login(w, r, user, true)
-					if err != nil {
-						throwInternalServiceError(s, w, r, "Login failed", err)
-						return
-					}
-					pageFrom := cookies.CheckPageFrom(w, r)
-					w.Header().Set("HX-Redirect", pageFrom)
-				}
-				return
+				pageFrom := cookies.CheckPageFrom(w, r)
+				w.Header().Set("HX-Redirect", pageFrom)
 			}
 		},
 	)
 }
-
-func registerUser(
-	ctx context.Context,
-	tx bun.Tx,
-	username string,
-	details *store.RegistrationSession,
-) (*db.User, error) {
-	unique, err := db.IsUsernameUnique(ctx, tx, username)
-	if err != nil {
-		return nil, errors.Wrap(err, "db.IsUsernameUnique")
-	}
-	if !unique {
-		return nil, nil
-	}
-	user, err := db.CreateUser(ctx, tx, username, details.DiscordUser)
-	if err != nil {
-		return nil, errors.Wrap(err, "db.CreateUser")
-	}
-	err = user.UpdateDiscordToken(ctx, tx, details.Token)
-	if err != nil {
-		return nil, errors.Wrap(err, "db.UpdateDiscordToken")
-	}
-	return user, nil
-}