Improve "must-change-password" logic and document (#30472)

Unify the behaviors of "user create" and "user change-password".

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>
(cherry picked from commit 4c6e2da088cf092a9790df5c84b7b338508fede7)

Conflicts:
	- cmd/admin_user_create.go
          Resolved by favoring Gitea's version of the conflicting areas.
	- docs/content/administration/command-line.en-us.md
          Removed, Gitea specific.

cmd/admin_user_change_password.go

@@ -36,6 +36,7 @@ var microcmdUserChangePassword = &cli.Command{
 		&cli.BoolFlag{
 			Name:  "must-change-password",
 			Usage: "User must change password",
+			Value: true,
 		},
 	},
 }
@@ -57,23 +58,18 @@ func runChangePassword(c *cli.Context) error {
 		return err
 	}
 
-	var mustChangePassword optional.Option[bool]
-	if c.IsSet("must-change-password") {
-		mustChangePassword = optional.Some(c.Bool("must-change-password"))
-	}
-
 	opts := &user_service.UpdateAuthOptions{
 		Password:           optional.Some(c.String("password")),
-		MustChangePassword: mustChangePassword,
+		MustChangePassword: optional.Some(c.Bool("must-change-password")),
 	}
 	if err := user_service.UpdateAuth(ctx, user, opts); err != nil {
 		switch {
 		case errors.Is(err, password.ErrMinLength):
-			return fmt.Errorf("Password is not long enough. Needs to be at least %d", setting.MinPasswordLength)
+			return fmt.Errorf("password is not long enough, needs to be at least %d characters", setting.MinPasswordLength)
 		case errors.Is(err, password.ErrComplexity):
-			return errors.New("Password does not meet complexity requirements")
+			return errors.New("password does not meet complexity requirements")
 		case errors.Is(err, password.ErrIsPwned):
-			return errors.New("The password you chose is on a list of stolen passwords previously exposed in public data breaches. Please try again with a different password.\nFor more details, see https://haveibeenpwned.com/Passwords")
+			return errors.New("the password is in a list of stolen passwords previously exposed in public data breaches, please try again with a different password, to see more details: https://haveibeenpwned.com/Passwords")
 		default:
 			return err
 		}

cmd/admin_user_create.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 
 	auth_model "code.gitea.io/gitea/models/auth"
+	"code.gitea.io/gitea/models/db"
 	user_model "code.gitea.io/gitea/models/user"
 	pwd "code.gitea.io/gitea/modules/auth/password"
 	"code.gitea.io/gitea/modules/optional"
@@ -46,9 +47,10 @@ var microcmdUserCreate = &cli.Command{
 			Usage: "Generate a random password for the user",
 		},
 		&cli.BoolFlag{
-			Name:  "must-change-password",
-			Usage: "Set this option to false to prevent forcing the user to change their password after initial login",
-			Value: true,
+			Name:               "must-change-password",
+			Usage:              "Set this option to false to prevent forcing the user to change their password after initial login",
+			Value:              true,
+			DisableDefaultText: true,
 		},
 		&cli.IntFlag{
 			Name:  "random-password-length",
@@ -72,10 +74,10 @@ func runCreateUser(c *cli.Context) error {
 	}
 
 	if c.IsSet("name") && c.IsSet("username") {
-		return errors.New("Cannot set both --name and --username flags")
+		return errors.New("cannot set both --name and --username flags")
 	}
 	if !c.IsSet("name") && !c.IsSet("username") {
-		return errors.New("One of --name or --username flags must be set")
+		return errors.New("one of --name or --username flags must be set")
 	}
 
 	if c.IsSet("password") && c.IsSet("random-password") {
@@ -111,12 +113,21 @@ func runCreateUser(c *cli.Context) error {
 		return errors.New("must set either password or random-password flag")
 	}
 
-	changePassword := c.Bool("must-change-password")
-
-	// If this is the first user being created.
-	// Take it as the admin and don't force a password update.
-	if n := user_model.CountUsers(ctx, nil); n == 0 {
-		changePassword = false
+	isAdmin := c.Bool("admin")
+	mustChangePassword := true // always default to true
+	if c.IsSet("must-change-password") {
+		// if the flag is set, use the value provided by the user
+		mustChangePassword = c.Bool("must-change-password")
+	} else {
+		// check whether there are users in the database
+		hasUserRecord, err := db.IsTableNotEmpty(&user_model.User{})
+		if err != nil {
+			return fmt.Errorf("IsTableNotEmpty: %w", err)
+		}
+		if !hasUserRecord && isAdmin {
+			// if this is the first admin being created, don't force to change password (keep the old behavior)
+			mustChangePassword = false
+		}
 	}
 
 	restricted := optional.None[bool]()
@@ -132,8 +143,8 @@ func runCreateUser(c *cli.Context) error {
 		Name:               username,
 		Email:              c.String("email"),
 		Passwd:             password,
-		IsAdmin:            c.Bool("admin"),
-		MustChangePassword: changePassword,
+		IsAdmin:            isAdmin,
+		MustChangePassword: mustChangePassword,
 		Visibility:         visibility,
 	}
 

models/db/engine.go

@@ -293,8 +293,8 @@ func MaxBatchInsertSize(bean any) int {
 }
 
 // IsTableNotEmpty returns true if table has at least one record
-func IsTableNotEmpty(tableName string) (bool, error) {
-	return x.Table(tableName).Exist()
+func IsTableNotEmpty(beanOrTableName any) (bool, error) {
+	return x.Table(beanOrTableName).Exist()
 }
 
 // DeleteAllRecords will delete all the records of this table