store: GetUserByOIDCSubject + scanUser auth_source/oidc_subject

internal/store/users.go

@@ -18,12 +18,18 @@ func (s *Store) CreateUser(ctx context.Context, u User) error {
 	if u.MustChangePassword {
 		must = 1
 	}
+	authSource := u.AuthSource
+	if authSource == "" {
+		authSource = "local"
+	}
 	_, err := s.db.ExecContext(ctx,
 		`INSERT INTO users (id, username, password_hash, role, email,
-		                    must_change_password, created_at)
-		 VALUES (?, ?, ?, ?, ?, ?, ?)`,
+		                    must_change_password, auth_source,
+		                    oidc_subject, created_at)
+		 VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
 		u.ID, u.Username, u.PasswordHash, string(u.Role),
-		nullable(u.Email), must,
+		nullable(u.Email), must, authSource,
+		nullable(u.OIDCSubject),
 		u.CreatedAt.UTC().Format(time.RFC3339Nano))
 	if err != nil {
 		return fmt.Errorf("store: create user: %w", err)
@@ -31,24 +37,49 @@ func (s *Store) CreateUser(ctx context.Context, u User) error {
 	return nil
 }
 
+// userSelectCols centralises the column list every read path uses so
+// scanUser stays in lockstep.
+const userSelectCols = `id, username, password_hash, role, email,
+                         disabled_at, must_change_password,
+                         auth_source, oidc_subject,
+                         created_at, last_login_at`
+
 // GetUserByUsername resolves a user case-insensitively.
 func (s *Store) GetUserByUsername(ctx context.Context, username string) (*User, error) {
 	row := s.db.QueryRowContext(ctx,
-		`SELECT id, username, password_hash, role, email, disabled_at,
-		        must_change_password, created_at, last_login_at
-		 FROM users WHERE LOWER(username) = LOWER(?)`, username)
+		`SELECT `+userSelectCols+` FROM users WHERE LOWER(username) = LOWER(?)`,
+		username)
 	return scanUser(row.Scan)
 }
 
 // GetUserByID looks up a user by id. Returns ErrNotFound on miss.
 func (s *Store) GetUserByID(ctx context.Context, id string) (*User, error) {
 	row := s.db.QueryRowContext(ctx,
-		`SELECT id, username, password_hash, role, email, disabled_at,
-		        must_change_password, created_at, last_login_at
-		 FROM users WHERE id = ?`, id)
+		`SELECT `+userSelectCols+` FROM users WHERE id = ?`, id)
 	return scanUser(row.Scan)
 }
 
+// GetUserByOIDCSubject finds the user JIT-provisioned on a previous
+// OIDC sign-in. ErrNotFound on miss.
+func (s *Store) GetUserByOIDCSubject(ctx context.Context, sub string) (*User, error) {
+	row := s.db.QueryRowContext(ctx,
+		`SELECT `+userSelectCols+` FROM users WHERE oidc_subject = ?`, sub)
+	return scanUser(row.Scan)
+}
+
+// SetUserOIDCSubject pins an existing user row to an IdP subject.
+// Used by tests today; reserved for a future "link a local user to
+// OIDC" flow.
+func (s *Store) SetUserOIDCSubject(ctx context.Context, id, authSource, sub string) error {
+	_, err := s.db.ExecContext(ctx,
+		`UPDATE users SET auth_source = ?, oidc_subject = ? WHERE id = ?`,
+		authSource, sub, id)
+	if err != nil {
+		return fmt.Errorf("store: set oidc subject: %w", err)
+	}
+	return nil
+}
+
 // UserSort selects the column ListUsers orders by. OrderBy is
 // allowlisted in usersOrderColumn so callers can't inject SQL via
 // this field. Empty / unknown OrderBy falls back to "username".
@@ -88,9 +119,8 @@ func (s *Store) ListUsers(ctx context.Context, sort UserSort) ([]User, error) {
 		// Default: username ASC (alphabetical), matching pre-sort behaviour.
 		asc = true
 	}
-	q := `SELECT id, username, password_hash, role, email, disabled_at,
-	             must_change_password, created_at, last_login_at
-	      FROM users ORDER BY ` + usersOrderColumn(sort.OrderBy, asc)
+	q := `SELECT ` + userSelectCols + ` FROM users ORDER BY ` +
+		usersOrderColumn(sort.OrderBy, asc)
 	rows, err := s.db.QueryContext(ctx, q)
 	if err != nil {
 		return nil, fmt.Errorf("store: list users: %w", err)
@@ -220,11 +250,13 @@ func (s *Store) SetPasswordHash(ctx context.Context, id, hash string) error {
 func scanUser(scan func(...any) error) (*User, error) {
 	var u User
 	var role string
-	var email, disabledAt, lastLogin sql.NullString
+	var email, disabledAt, oidcSub, lastLogin sql.NullString
 	var must int
+	var authSource string
 	var created string
 	if err := scan(&u.ID, &u.Username, &u.PasswordHash, &role,
-		&email, &disabledAt, &must, &created, &lastLogin); err != nil {
+		&email, &disabledAt, &must, &authSource, &oidcSub,
+		&created, &lastLogin); err != nil {
 		if errors.Is(err, sql.ErrNoRows) {
 			return nil, ErrNotFound
 		}
@@ -240,6 +272,11 @@ func scanUser(scan func(...any) error) (*User, error) {
 		u.DisabledAt = &t
 	}
 	u.MustChangePassword = must == 1
+	u.AuthSource = authSource
+	if oidcSub.Valid {
+		v := oidcSub.String
+		u.OIDCSubject = &v
+	}
 	t, _ := time.Parse(time.RFC3339Nano, created)
 	u.CreatedAt = t
 	if lastLogin.Valid {

internal/store/users_test.go

@@ -165,6 +165,54 @@ func TestCreateUserLowercasesUsername(t *testing.T) {
 	}
 }
 
+func TestGetUserByOIDCSubject(t *testing.T) {
+	t.Parallel()
+	s := openTestStore(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+	sub := "sub-abc-123"
+
+	if err := s.CreateUser(ctx, User{
+		ID: "u1", Username: "alice", PasswordHash: "",
+		Role: RoleAdmin, CreatedAt: now,
+		AuthSource: "oidc", OIDCSubject: &sub,
+	}); err != nil {
+		t.Fatalf("create: %v", err)
+	}
+	got, err := s.GetUserByOIDCSubject(ctx, sub)
+	if err != nil {
+		t.Fatalf("get by sub: %v", err)
+	}
+	if got.ID != "u1" || got.AuthSource != "oidc" {
+		t.Errorf("unexpected: %+v", got)
+	}
+	if _, err := s.GetUserByOIDCSubject(ctx, "nope"); !errors.Is(err, ErrNotFound) {
+		t.Errorf("missing sub: want ErrNotFound, got %v", err)
+	}
+}
+
+func TestSetUserOIDCSubject(t *testing.T) {
+	t.Parallel()
+	s := openTestStore(t)
+	ctx := context.Background()
+	now := time.Now().UTC()
+
+	if err := s.CreateUser(ctx, User{
+		ID: "u1", Username: "alice", PasswordHash: "x",
+		Role: RoleAdmin, CreatedAt: now,
+	}); err != nil {
+		t.Fatalf("create: %v", err)
+	}
+	sub := "sub-456"
+	if err := s.SetUserOIDCSubject(ctx, "u1", "oidc", sub); err != nil {
+		t.Fatalf("set: %v", err)
+	}
+	got, _ := s.GetUserByID(ctx, "u1")
+	if got.AuthSource != "oidc" || got.OIDCSubject == nil || *got.OIDCSubject != sub {
+		t.Errorf("after set: %+v", got)
+	}
+}
+
 func TestEnrollmentTokenSingleUse(t *testing.T) {
 	t.Parallel()
 	s := openTestStore(t)