Memebrships: Refactor Store interface

Use unified memberships table.
Add few internal API endpoints.

Change-Id: I80ac5a0f5c262e04d7898cca571b938a35d68d39
diff --git a/core/auth/memberships/store.go b/core/auth/memberships/store.go
new file mode 100644
index 0000000..05b09bc
--- /dev/null
+++ b/core/auth/memberships/store.go
@@ -0,0 +1,690 @@
+package main
+
+import (
+	"database/sql"
+	_ "embed"
+	"fmt"
+	"strings"
+
+	"github.com/ncruces/go-sqlite3"
+)
+
+//go:embed schema.sql
+var schema string
+
+const (
+	ErrorUniqueConstraintViolation     = 2067
+	ErrorConstraintPrimaryKeyViolation = 1555
+)
+
+type scanner interface {
+	Scan(dest ...any) error
+}
+
+type Store interface {
+	// Initializes store with admin user and their groups.
+	Init(user User, groups []Group) error
+	CreateUser(tx *sql.Tx, user User) error
+	GetAllUsers(tx *sql.Tx) ([]User, error)
+	GetUser(tx *sql.Tx, id string) (User, error)
+	GetUsers(tx *sql.Tx, ids []string) ([]User, error)
+	CreateGroup(tx *sql.Tx, userId string, group Group) error
+	GetGroup(tx *sql.Tx, id string) (Group, error)
+	GetAllGroups(tx *sql.Tx) ([]Group, error)
+	AddMemberUser(tx *sql.Tx, groupId, userId string) error
+	AddOwnerUser(tx *sql.Tx, groupId, userId string) error
+	AddMemberGroup(tx *sql.Tx, groupId, otherId string) error
+	AddOwnerGroup(tx *sql.Tx, groupId, otherId string) error
+	GetMemberUsers(tx *sql.Tx, groupId string) ([]User, error)
+	GetOwnerUsers(tx *sql.Tx, groupId string) ([]User, error)
+	GetMemberGroups(tx *sql.Tx, groupId string) ([]Group, error)
+	GetOwnerGroups(tx *sql.Tx, groupId string) ([]Group, error)
+	RemoveMemberUser(tx *sql.Tx, groupId, userId string) error
+	RemoveOwnerUser(tx *sql.Tx, groupId, userId string) error
+	RemoveMemberGroup(tx *sql.Tx, groupId, otherId string) error
+	RemoveOwnerGroup(tx *sql.Tx, groupId, otherId string) error
+	GetGroupsUserCanActAs(tx *sql.Tx, userId string) ([]Group, error)
+	GetGroupsGroupCanActAs(tx *sql.Tx, groupId string) ([]Group, error)
+	GetGroupsUserOwns(tx *sql.Tx, userId string) ([]Group, error)
+	GetGroupsUserIsMemberOf(tx *sql.Tx, userId string) ([]Group, error)
+	GetUserPublicKeys(tx *sql.Tx, userId string) ([]string, error)
+	AddUserPublicKey(tx *sql.Tx, userId, publicKey string) error
+	RemoveUserPublicKey(tx *sql.Tx, userId, publicKey string) error
+}
+
+type SQLiteStore struct {
+	db *sql.DB
+}
+
+func NewSQLiteStore(db *sql.DB) (*SQLiteStore, error) {
+	_, err := db.Exec(schema)
+	if err != nil {
+		return nil, err
+	}
+	return &SQLiteStore{db: db}, nil
+}
+
+func (s *SQLiteStore) Init(user User, groups []Group) error {
+	tx, err := s.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+	row := tx.QueryRow("SELECT COUNT(*) FROM groups")
+	var count int
+	if err := row.Scan(&count); err != nil {
+		return err
+	}
+	if count != 0 {
+		return fmt.Errorf("Store already initialised")
+	}
+	if err := s.CreateUser(tx, user); err != nil {
+		return err
+	}
+	for _, g := range groups {
+		if err := s.CreateGroup(tx, user.Id, g); err != nil {
+			return err
+		}
+		if err := s.AddMemberUser(tx, g.Id, user.Id); err != nil {
+			return err
+		}
+	}
+	return tx.Commit()
+}
+
+func (s *SQLiteStore) CreateUser(tx *sql.Tx, user User) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "INSERT INTO users (id, username, email) VALUES (?, ?, ?)"
+	_, err = tx.Exec(query, user.Id, user.Username, user.Email)
+	return
+}
+
+func (s *SQLiteStore) scanUser(row scanner) (User, error) {
+	var ret User
+	if err := row.Scan(&ret.Id, &ret.Username, &ret.Email); err != nil {
+		return User{}, err
+	}
+	return ret, nil
+}
+
+func (s *SQLiteStore) scanUsers(rows *sql.Rows) ([]User, error) {
+	var ret []User
+	for rows.Next() {
+		if u, err := s.scanUser(rows); err != nil {
+			return nil, err
+		} else {
+			ret = append(ret, u)
+		}
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return ret, nil
+}
+
+func (s *SQLiteStore) scanGroup(row scanner) (Group, error) {
+	var ret Group
+	if err := row.Scan(&ret.Id, &ret.Title, &ret.Description); err != nil {
+		return Group{}, err
+	}
+	return ret, nil
+}
+
+func (s *SQLiteStore) scanGroups(rows *sql.Rows) ([]Group, error) {
+	var ret []Group
+	for rows.Next() {
+		if g, err := s.scanGroup(rows); err != nil {
+			return nil, err
+		} else {
+			ret = append(ret, g)
+		}
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return ret, nil
+}
+
+func (s *SQLiteStore) GetAllUsers(tx *sql.Tx) (ret []User, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "SELECT id, username, email FROM users"
+	var rows *sql.Rows
+	if rows, err = tx.Query(query); err == nil {
+		ret, err = s.scanUsers(rows)
+	}
+	return
+}
+
+func (s *SQLiteStore) GetUser(tx *sql.Tx, id string) (ret User, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "SELECT id, username, email FROM users WHERE id = ?"
+	row := tx.QueryRow(query, id)
+	ret, err = s.scanUser(row)
+	return
+}
+
+func (s *SQLiteStore) GetUsers(tx *sql.Tx, ids []string) (ret []User, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	idPlaceholders := make([]string, len(ids))
+	idParams := make([]any, len(ids))
+	for i, id := range ids {
+		idPlaceholders[i] = "?"
+		idParams[i] = id
+	}
+	query := fmt.Sprintf("SELECT id, username, email FROM users WHERE id IN (%s)", strings.Join(idPlaceholders, ", "))
+	var rows *sql.Rows
+	if rows, err = tx.Query(query, idParams...); err == nil {
+		ret, err = s.scanUsers(rows)
+	}
+	return
+}
+
+func (s *SQLiteStore) CreateGroup(tx *sql.Tx, userId string, group Group) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "INSERT INTO groups (id, title, description) VALUES (?, ?, ?)"
+	if _, err = tx.Exec(query, group.Id, group.Title, group.Description); err != nil {
+		sqliteErr, ok := err.(*sqlite3.Error)
+		if ok && sqliteErr.ExtendedCode() == ErrorConstraintPrimaryKeyViolation {
+			err = fmt.Errorf("Group with id %s already exists", group.Id)
+		}
+		return
+	}
+	err = s.addUser(tx, group.Id, userId, "owner")
+	return
+}
+
+func (s *SQLiteStore) GetGroup(tx *sql.Tx, id string) (ret Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "SELECT id, title, description FROM groups WHERE id = ?"
+	row := tx.QueryRow(query, id)
+	ret, err = s.scanGroup(row)
+	return
+}
+func (s *SQLiteStore) GetAllGroups(tx *sql.Tx) (ret []Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "SELECT id, title, description FROM groups"
+	var rows *sql.Rows
+	if rows, err = tx.Query(query); err == nil {
+		ret, err = s.scanGroups(rows)
+	}
+	return
+}
+
+func (s *SQLiteStore) addUser(tx *sql.Tx, groupId, userId, membershipType string) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "INSERT INTO memberships (id, membership_type, member_type, user_id) VALUES (?, ?, ?, ?)"
+	_, err = tx.Exec(query, groupId, membershipType, "user", userId)
+	return
+}
+
+func (s *SQLiteStore) addGroup(tx *sql.Tx, groupId, otherId, membershipType string) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "INSERT INTO memberships (id, membership_type, member_type, group_id) VALUES (?, ?, ?, ?)"
+	_, err = tx.Exec(query, groupId, membershipType, "group", otherId)
+	return
+}
+
+func (s *SQLiteStore) removeUser(tx *sql.Tx, groupId, userId, membershipType string) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "DELETE FROM memberships WHERE id = ? AND membership_type = ? AND member_type = ? AND user_id = ?"
+	_, err = tx.Exec(query, groupId, membershipType, "user", userId)
+	return
+}
+
+func (s *SQLiteStore) removeGroup(tx *sql.Tx, groupId, otherId, membershipType string) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "DELETE FROM memberships WHERE id = ? AND membership_type = ? AND member_type = ? AND group_id = ?"
+	_, err = tx.Exec(query, groupId, membershipType, "group", otherId)
+	return
+}
+
+func (s *SQLiteStore) getUsers(tx *sql.Tx, groupId, membershipType string) (ret []User, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := `
+SELECT u.id, u.username, u.email
+FROM users u
+JOIN memberships m
+ON u.id = m.user_id
+WHERE m.id = ? AND membership_type = ? AND member_type = ?
+`
+	var rows *sql.Rows
+	rows, err = tx.Query(query, groupId, membershipType, "user")
+	if err != nil {
+		return
+	}
+	ret, err = s.scanUsers(rows)
+	return
+}
+
+func (s *SQLiteStore) getGroups(tx *sql.Tx, groupId, membershipType string) (ret []Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := `
+SELECT g.id, g.title, g.description
+FROM groups AS g
+JOIN memberships AS m
+ON g.id = m.group_id
+WHERE m.id = ? AND m.membership_type = ? AND m.member_type = ?`
+	var rows *sql.Rows
+	if rows, err = tx.Query(query, groupId, membershipType, "group"); err == nil {
+		ret, err = s.scanGroups(rows)
+	}
+	return
+}
+
+func (s *SQLiteStore) AddMemberUser(tx *sql.Tx, groupId, userId string) error {
+	return s.addUser(tx, groupId, userId, "member")
+}
+
+func (s *SQLiteStore) AddOwnerUser(tx *sql.Tx, groupId, userId string) error {
+	return s.addUser(tx, groupId, userId, "owner")
+}
+
+func (s *SQLiteStore) AddMemberGroup(tx *sql.Tx, groupId, otherId string) error {
+	return s.addGroup(tx, groupId, otherId, "member")
+}
+
+func (s *SQLiteStore) AddOwnerGroup(tx *sql.Tx, groupId, otherId string) error {
+	return s.addGroup(tx, groupId, otherId, "owner")
+}
+
+func (s *SQLiteStore) GetMemberUsers(tx *sql.Tx, groupId string) ([]User, error) {
+	return s.getUsers(tx, groupId, "member")
+}
+
+func (s *SQLiteStore) GetOwnerUsers(tx *sql.Tx, groupId string) ([]User, error) {
+	return s.getUsers(tx, groupId, "owner")
+}
+
+func (s *SQLiteStore) GetMemberGroups(tx *sql.Tx, groupId string) ([]Group, error) {
+	return s.getGroups(tx, groupId, "member")
+}
+
+func (s *SQLiteStore) GetOwnerGroups(tx *sql.Tx, groupId string) ([]Group, error) {
+	return s.getGroups(tx, groupId, "owner")
+}
+
+func (s *SQLiteStore) RemoveMemberUser(tx *sql.Tx, groupId, userId string) error {
+	return s.removeUser(tx, groupId, userId, "member")
+}
+
+func (s *SQLiteStore) RemoveOwnerUser(tx *sql.Tx, groupId, userId string) error {
+	return s.removeUser(tx, groupId, userId, "owner")
+}
+
+func (s *SQLiteStore) RemoveMemberGroup(tx *sql.Tx, groupId, otherId string) error {
+	return s.removeGroup(tx, groupId, otherId, "member")
+}
+
+func (s *SQLiteStore) RemoveOwnerGroup(tx *sql.Tx, groupId, otherId string) error {
+	return s.removeGroup(tx, groupId, otherId, "owner")
+}
+
+func (s *SQLiteStore) traverseGroups(tx *sql.Tx, groups ...Group) ([]Group, error) {
+	seen := map[string]struct{}{}
+	for _, g := range groups {
+		seen[g.Id] = struct{}{}
+	}
+	for i := 0; i < len(groups); i++ {
+		g := groups[i]
+		parents, err := s.getGroupGroups(tx, g.Id, "member")
+		if err != nil {
+			return nil, err
+		}
+		for _, p := range parents {
+			if _, ok := seen[p.Id]; !ok {
+				groups = append(groups, p)
+				seen[p.Id] = struct{}{}
+			}
+		}
+	}
+	return groups, nil
+}
+
+func (s *SQLiteStore) GetGroupsUserCanActAs(tx *sql.Tx, userId string) (ret []Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	var memberOf []Group
+	memberOf, err = s.GetGroupsUserIsMemberOf(tx, userId)
+	if err != nil {
+		return
+	}
+	ret, err = s.traverseGroups(tx, memberOf...)
+	return
+}
+
+func (s *SQLiteStore) GetGroupsGroupCanActAs(tx *sql.Tx, groupId string) (ret []Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	var g Group
+	g, err = s.GetGroup(tx, groupId)
+	if err != nil {
+		return
+	}
+	var groups []Group
+	if groups, err = s.traverseGroups(tx, g); err == nil {
+		ret = groups[1:]
+	}
+	return
+}
+
+func (s *SQLiteStore) getUserGroups(tx *sql.Tx, userId, membershipType string) (ret []Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			}
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := `
+SELECT g.id, g.title, g.description
+FROM groups AS g
+JOIN memberships AS m
+ON g.id = m.id
+WHERE m.user_id = ? AND m.membership_type = ? AND m.member_type = ?`
+	var rows *sql.Rows
+	if rows, err = tx.Query(query, userId, membershipType, "user"); err == nil {
+		ret, err = s.scanGroups(rows)
+	}
+	return
+}
+
+func (s *SQLiteStore) getGroupGroups(tx *sql.Tx, groupId, membershipType string) (ret []Group, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := `
+SELECT g.id, g.title, g.description
+FROM groups AS g
+JOIN memberships AS m
+ON g.id = m.id
+WHERE m.group_id = ? AND m.membership_type = ? AND m.member_type = ?`
+	var rows *sql.Rows
+	if rows, err = tx.Query(query, groupId, membershipType, "group"); err == nil {
+		ret, err = s.scanGroups(rows)
+	}
+	return
+}
+
+func (s *SQLiteStore) GetGroupsUserOwns(tx *sql.Tx, userId string) ([]Group, error) {
+	return s.getUserGroups(tx, userId, "owner")
+}
+
+func (s *SQLiteStore) GetGroupsUserIsMemberOf(tx *sql.Tx, userId string) ([]Group, error) {
+	return s.getUserGroups(tx, userId, "member")
+}
+
+func (s *SQLiteStore) AddUserPublicKey(tx *sql.Tx, userId, publicKey string) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "INSERT INTO keys (user_id, public_key) VALUES (?, ?)"
+	_, err = tx.Exec(query, userId, publicKey)
+	return
+}
+
+func (s *SQLiteStore) GetUserPublicKeys(tx *sql.Tx, userId string) (ret []string, err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "SELECT public_key FROM keys WHERE user_id = ?"
+	var rows *sql.Rows
+	if rows, err = tx.Query(query, userId); err != nil {
+		return
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var publicKey string
+		if err = rows.Scan(&publicKey); err != nil {
+			return
+		}
+		ret = append(ret, publicKey)
+	}
+	err = rows.Err()
+	return
+}
+
+func (s *SQLiteStore) RemoveUserPublicKey(tx *sql.Tx, userId, publicKey string) (err error) {
+	if tx == nil {
+		tx, err = s.db.Begin()
+		if err != nil {
+			return
+		}
+		defer func() {
+			if err == nil {
+				err = tx.Commit()
+			} else {
+				tx.Rollback()
+			}
+		}()
+	}
+	query := "DELETE FROM keys WHERE user_id = ? AND  public_key = ?"
+	_, err = tx.Exec(query, userId, publicKey)
+	return
+}