mv 'env/stack{,_*}.go' => 'env/component{,_*}.go'

env/component_sql.go

@@ -0,0 +1,241 @@
+package env
+
+import (
+	"fmt"
+	"io"
+	"io/fs"
+	"time"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/bookkeeping"
+	"github.com/FAU-CDI/wisski-distillery/internal/logging"
+	"github.com/FAU-CDI/wisski-distillery/internal/sqle"
+	"github.com/FAU-CDI/wisski-distillery/internal/stack"
+	"github.com/FAU-CDI/wisski-distillery/internal/wait"
+	"github.com/pkg/errors"
+	"github.com/tkw1536/goprogram/stream"
+	"gorm.io/driver/mysql"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+// SQLComponent represents the 'sql' layer belonging to a distillery
+type SQLComponent struct {
+	PollInterval time.Duration // Duration to wait for during wait
+
+	dis *Distillery
+}
+
+// SSH returns the SSHComponent belonging to this distillery
+func (dis *Distillery) SQL() SQLComponent {
+	return SQLComponent{
+		PollInterval: time.Second,
+
+		dis: dis,
+	}
+}
+
+func (SQLComponent) Name() string {
+	return "sql"
+}
+
+// Stack returns the docker stack that handles the sql database.
+func (sql SQLComponent) Stack() stack.Installable {
+	return sql.dis.makeComponentStack(sql, stack.Installable{
+		MakeDirsPerm: fs.ModeDir | fs.ModePerm,
+		MakeDirs: []string{
+			"data",
+		},
+	})
+}
+
+// SQLStackPath returns the path the SQLStack() lives at.
+func (sql SQLComponent) Path() string {
+	return sql.Stack().Dir
+}
+
+// sqlOpen opens a new sql connection to the provided database using the administrative credentials
+func (sql SQLComponent) openDatabase(database string, config *gorm.Config) (*gorm.DB, error) {
+	cfg := mysql.Config{
+		DSN:               fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=utf8&parseTime=True&loc=Local", sql.dis.Config.MysqlAdminUser, sql.dis.Config.MysqlAdminPassword, "127.0.0.1:3306", database),
+		DefaultStringSize: 256,
+	}
+
+	db, err := gorm.Open(mysql.New(cfg), config)
+	if err != nil {
+		return db, err
+	}
+
+	gdb, err := db.DB()
+	if err != nil {
+		return db, err
+	}
+	gdb.SetMaxIdleConns(0)
+
+	return db, nil
+}
+
+// OpenBookkeeping opens a connection to the bookkeeping database
+func (sql SQLComponent) OpenBookkeeping(silent bool) (*gorm.DB, error) {
+
+	config := &gorm.Config{}
+	if silent {
+		config.Logger = logger.Default.LogMode(logger.Silent)
+	}
+
+	// open the database
+	db, err := sql.openDatabase(sql.dis.Config.DistilleryBookkeepingDatabase, config)
+	if err != nil {
+		return nil, err
+	}
+
+	// load the table
+	table := db.Table(sql.dis.Config.DistilleryBookkeepingTable)
+	if table.Error != nil {
+		return nil, err
+	}
+
+	return table, nil
+}
+
+var errSQLBackup = errors.New("SQLBackup: Mysqldump returned non-zero exit code")
+
+// Backup makes a backup of the sql database into dest.
+func (sql SQLComponent) Backup(io stream.IOStream, dest io.Writer, database string) error {
+	io = stream.NewIOStream(dest, io.Stderr, nil, 0)
+
+	code, err := sql.Stack().Exec(io, "sql", "mysqldump", "--database", database)
+	if err != nil {
+		return err
+	}
+	if code != 0 {
+		return errSQLBackup
+	}
+	return nil
+}
+
+// OpenShell executes a mysql shell command
+func (sql SQLComponent) OpenShell(io stream.IOStream, argv ...string) (int, error) {
+	return sql.Stack().Exec(io, "sql", "mysql", argv...)
+}
+
+// WaitShell waits for the sql database to be reachable via a docker-compose shell
+func (sql SQLComponent) WaitShell() error {
+	n := stream.FromNil()
+	return wait.Wait(func() bool {
+		code, err := sql.OpenShell(n, "-e", "show databases;")
+		return err == nil && code == 0
+	}, sql.PollInterval, sql.dis.Context())
+}
+
+// Wait waits for a connection to the bookkeeping table to suceed
+func (sql SQLComponent) Wait() error {
+	return wait.Wait(func() bool {
+		_, err := sql.OpenBookkeeping(true)
+		return err == nil
+	}, sql.PollInterval, sql.dis.Context())
+}
+
+var errInvalidDatabaseName = errors.New("SQLProvision: Invalid database name")
+
+func (sql SQLComponent) Query(query string, args ...interface{}) bool {
+	raw := sqle.Format(query, args...)
+	code, err := sql.OpenShell(stream.FromNil(), "-e", raw)
+	return err == nil && code == 0
+}
+
+// SQLProvision provisions a new sql database and user
+func (sql SQLComponent) Provision(name, user, password string) error {
+	// wait for the database
+	if err := sql.WaitShell(); err != nil {
+		return err
+	}
+
+	// it's not a safe database name!
+	if !sqle.IsSafeDatabaseName(name) {
+		return errInvalidDatabaseName
+	}
+
+	// create the database and user!
+	if !sql.Query("CREATE DATABASE `"+name+"`; CREATE USER ?@`%` IDENTIFIED BY ?; GRANT ALL PRIVILEGES ON `"+name+"`.* TO ?@`%`; FLUSH PRIVILEGES;", user, password, user) {
+		return errors.New("SQLProvision: Failed to create user")
+	}
+
+	// and done!
+	return nil
+}
+
+var errSQLPurgeUser = errors.New("unable to delete user")
+
+// SQLPurgeUser deletes the specified user from the database
+func (sql SQLComponent) PurgeUser(user string) error {
+	if !sql.Query("DROP USER IF EXISTS ?@`%`; FLUSH PRIVILEGES; ", user) {
+		return errSQLPurgeUser
+	}
+
+	return nil
+}
+
+var errSQLPurgeDB = errors.New("unable to drop database")
+
+// SQLPurgeDatabase deletes the specified db from the database
+func (sql SQLComponent) PurgeDatabase(db string) error {
+	if !sqle.IsSafeDatabaseName(db) {
+		return errSQLPurgeDB
+	}
+	if !sql.Query("DROP DATABASE IF EXISTS `" + db + "`") {
+		return errSQLPurgeDB
+	}
+	return nil
+}
+
+var errSQLUnableToCreateUser = errors.New("unable to create administrative user")
+var errSQLUnsafeDatabaseName = errors.New("Bookkeeping database has an unsafe name")
+var errSQLUnableToCreate = errors.New("unable to create bookkeeping database")
+
+// Bootstrap bootstraps the SQL database, and makes sure that the bookkeeping table is up-to-date
+func (sql SQLComponent) Bootstrap(io stream.IOStream) error {
+	if err := sql.WaitShell(); err != nil {
+		return err
+	}
+
+	// create the admin user
+	logging.LogMessage(io, "Creating administrative user")
+	{
+		username := sql.dis.Config.MysqlAdminUser
+		password := sql.dis.Config.MysqlAdminPassword
+		if !sql.Query("CREATE USER IF NOT EXISTS ?@'%' IDENTIFIED BY ?; GRANT ALL PRIVILEGES ON *.* TO ?@`%` WITH GRANT OPTION; FLUSH PRIVILEGES;", username, password, username) {
+			return errSQLUnableToCreateUser
+		}
+	}
+
+	// create the admin user
+	logging.LogMessage(io, "Creating sql database")
+	{
+		if !sqle.IsSafeDatabaseName(sql.dis.Config.DistilleryBookkeepingDatabase) {
+			return errSQLUnsafeDatabaseName
+		}
+		createDBSQL := fmt.Sprintf("CREATE DATABASE IF NOT EXISTS `%s`;", sql.dis.Config.DistilleryBookkeepingDatabase)
+		if !sql.Query(createDBSQL) {
+			return errSQLUnableToCreate
+		}
+	}
+
+	// wait for the database to come up
+	logging.LogMessage(io, "Waiting for database update to be complete")
+	sql.Wait()
+
+	// open the database
+	logging.LogMessage(io, "Migrating bookkeeping table")
+	{
+		db, err := sql.OpenBookkeeping(false)
+		if err != nil {
+			return fmt.Errorf("unable to access bookkeeping table: %s", err)
+		}
+
+		if err := db.AutoMigrate(&bookkeeping.Instance{}); err != nil {
+			return fmt.Errorf("unable to migrate bookkeeping table: %s", err)
+		}
+	}
+
+	return nil
+}