Addressing review comments

reverting query string caching in favour of Go 1.9 sqlx features
 moving context definition out of call.End to upper level

api/datastore/sql/sql.go

@@ -71,23 +71,10 @@ const (
 )
 
 type sqlStore struct {
-	db                   *sqlx.DB
-	insertAppQuery       string
-	updateAppQuery       string
-	getAppQuery          string
-	selectAppConfigQuery string
-	removeAppQuery       string
-	insertRouteQuery     string
-	updateRouteQuery     string
-	checkRouteAppQuery   string
-	checkRouteQuery      string
-	getRouteQuery        string
-	removeRouteQuery     string
-	insertCallQuery      string
-	getCallQuery         string
-	insertLogQuery       string
-	getLogQuery          string
-	deleteLogQuery       string
+	db *sqlx.DB
+
+	// TODO we should prepare all of the statements, rebind them
+	// and store them all here.
 }
 
 // New will open the db specified by url, create any tables necessary
@@ -146,56 +133,7 @@ func New(url *url.URL) (models.Datastore, error) {
 		}
 	}
 
-	dstore := &sqlStore{
-		db:                   db,
-		insertAppQuery:       db.Rebind("INSERT INTO apps (name, config) VALUES (?, ?);"),
-		selectAppConfigQuery: db.Rebind(`SELECT config FROM apps WHERE name=?`),
-		updateAppQuery:       db.Rebind(`UPDATE apps SET config=? WHERE name=?`),
-		removeAppQuery:       db.Rebind(`DELETE FROM apps WHERE name = ?`),
-		getAppQuery:          db.Rebind(`SELECT name, config FROM apps WHERE name=?`),
-		checkRouteAppQuery:   db.Rebind(`SELECT 1 FROM apps WHERE name=?`),
-		checkRouteQuery:      db.Rebind(`SELECT 1 FROM routes WHERE app_name=? AND path=?`),
-		insertRouteQuery: db.Rebind(`INSERT INTO routes (
-			app_name,
-			path,
-			image,
-			format,
-			memory,
-			type,
-			timeout,
-			idle_timeout,
-			headers,
-			config
-		)
-		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?);`),
-		getRouteQuery: db.Rebind(fmt.Sprintf("%s WHERE app_name=? AND path=?", routeSelector)),
-		updateRouteQuery: db.Rebind(`UPDATE routes SET
-			image = ?,
-			format = ?,
-			memory = ?,
-			type = ?,
-			timeout = ?,
-			idle_timeout = ?,
-			headers = ?,
-			config = ?
-		WHERE app_name=? AND path=?;`),
-		removeRouteQuery: db.Rebind(`DELETE FROM routes WHERE path = ? AND app_name = ?`),
-		insertCallQuery: db.Rebind(`INSERT INTO calls (
-			id,
-			created_at,
-			started_at,
-			completed_at,
-			status,
-			app_name,
-			path
-		)
-		VALUES (?, ?, ?, ?, ?, ?, ?);`),
-		getCallQuery:   db.Rebind(fmt.Sprintf(`%s WHERE id=? AND app_name=?`, callSelector)),
-		insertLogQuery: db.Rebind(`INSERT INTO logs (id, log) VALUES (?, ?);`),
-		getLogQuery:    db.Rebind(`SELECT log FROM logs WHERE id=?`),
-		deleteLogQuery: db.Rebind(`DELETE FROM logs WHERE id=?`),
-	}
-	return dstore, nil
+	return &sqlStore{db: db}, nil
 }
 
 func (ds *sqlStore) InsertApp(ctx context.Context, app *models.App) (*models.App, error) {
@@ -208,7 +146,8 @@ func (ds *sqlStore) InsertApp(ctx context.Context, app *models.App) (*models.App
 		}
 	}
 
-	_, err = ds.db.ExecContext(ctx, ds.insertAppQuery, app.Name, string(cbyte))
+	query := ds.db.Rebind("INSERT INTO apps (name, config) VALUES (?, ?);")
+	_, err = ds.db.ExecContext(ctx, query, app.Name, string(cbyte))
 	if err != nil {
 		switch err := err.(type) {
 		case *mysql.MySQLError:
@@ -233,7 +172,8 @@ func (ds *sqlStore) InsertApp(ctx context.Context, app *models.App) (*models.App
 func (ds *sqlStore) UpdateApp(ctx context.Context, newapp *models.App) (*models.App, error) {
 	app := &models.App{Name: newapp.Name}
 	err := ds.Tx(func(tx *sqlx.Tx) error {
-		row := tx.QueryRowContext(ctx, ds.selectAppConfigQuery, app.Name)
+		query := tx.Rebind(`SELECT config FROM apps WHERE name=?`)
+		row := tx.QueryRowContext(ctx, query, app.Name)
 
 		var config string
 		if err := row.Scan(&config); err != nil {
@@ -257,7 +197,8 @@ func (ds *sqlStore) UpdateApp(ctx context.Context, newapp *models.App) (*models.
 			return err
 		}
 
-		res, err := tx.ExecContext(ctx, ds.updateAppQuery, string(cbyte), app.Name)
+		query = tx.Rebind(`UPDATE apps SET config=? WHERE name=?`)
+		res, err := tx.ExecContext(ctx, query, string(cbyte), app.Name)
 		if err != nil {
 			return err
 		}
@@ -279,12 +220,14 @@ func (ds *sqlStore) UpdateApp(ctx context.Context, newapp *models.App) (*models.
 }
 
 func (ds *sqlStore) RemoveApp(ctx context.Context, appName string) error {
-	_, err := ds.db.ExecContext(ctx, ds.removeAppQuery, appName)
+	query := ds.db.Rebind(`DELETE FROM apps WHERE name = ?`)
+	_, err := ds.db.ExecContext(ctx, query, appName)
 	return err
 }
 
 func (ds *sqlStore) GetApp(ctx context.Context, name string) (*models.App, error) {
-	row := ds.db.QueryRowContext(ctx, ds.getAppQuery, name)
+	query := ds.db.Rebind(`SELECT name, config FROM apps WHERE name=?`)
+	row := ds.db.QueryRowContext(ctx, query, name)
 
 	var resName, config string
 	err := row.Scan(&resName, &config)
@@ -351,13 +294,15 @@ func (ds *sqlStore) InsertRoute(ctx context.Context, route *models.Route) (*mode
 	}
 
 	err = ds.Tx(func(tx *sqlx.Tx) error {
-		r := tx.QueryRowContext(ctx, ds.checkRouteAppQuery, route.AppName)
+		query := tx.Rebind(`SELECT 1 FROM apps WHERE name=?`)
+		r := tx.QueryRowContext(ctx, query, route.AppName)
 		if err := r.Scan(new(int)); err != nil {
 			if err == sql.ErrNoRows {
 				return models.ErrAppsNotFound
 			}
 		}
-		same, err := tx.QueryContext(ctx, ds.checkRouteQuery, route.AppName, route.Path)
+		query = tx.Rebind(`SELECT 1 FROM routes WHERE app_name=? AND path=?`)
+		same, err := tx.QueryContext(ctx, query, route.AppName, route.Path)
 		if err != nil {
 			return err
 		}
@@ -366,7 +311,21 @@ func (ds *sqlStore) InsertRoute(ctx context.Context, route *models.Route) (*mode
 			return models.ErrRoutesAlreadyExists
 		}
 
-		_, err = tx.ExecContext(ctx, ds.insertRouteQuery,
+		query = tx.Rebind(`INSERT INTO routes (
+			app_name,
+			path,
+			image,
+			format,
+			memory,
+			type,
+			timeout,
+			idle_timeout,
+			headers,
+			config
+		)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?);`)
+
+		_, err = tx.ExecContext(ctx, query,
 			route.AppName,
 			route.Path,
 			route.Image,
@@ -388,7 +347,8 @@ func (ds *sqlStore) InsertRoute(ctx context.Context, route *models.Route) (*mode
 func (ds *sqlStore) UpdateRoute(ctx context.Context, newroute *models.Route) (*models.Route, error) {
 	var route models.Route
 	err := ds.Tx(func(tx *sqlx.Tx) error {
-		row := tx.QueryRowContext(ctx, ds.getRouteQuery, newroute.AppName, newroute.Path)
+		query := tx.Rebind(fmt.Sprintf("%s WHERE app_name=? AND path=?", routeSelector))
+		row := tx.QueryRowContext(ctx, query, newroute.AppName, newroute.Path)
 		if err := scanRoute(row, &route); err == sql.ErrNoRows {
 			return models.ErrRoutesNotFound
 		} else if err != nil {
@@ -407,7 +367,18 @@ func (ds *sqlStore) UpdateRoute(ctx context.Context, newroute *models.Route) (*m
 			return err
 		}
 
-		res, err := tx.ExecContext(ctx, ds.updateRouteQuery,
+		query = tx.Rebind(`UPDATE routes SET
+			image = ?,
+			format = ?,
+			memory = ?,
+			type = ?,
+			timeout = ?,
+			idle_timeout = ?,
+			headers = ?,
+			config = ?
+		WHERE app_name=? AND path=?;`)
+
+		res, err := tx.ExecContext(ctx, query,
 			route.Image,
 			route.Format,
 			route.Memory,
@@ -441,7 +412,8 @@ func (ds *sqlStore) UpdateRoute(ctx context.Context, newroute *models.Route) (*m
 }
 
 func (ds *sqlStore) RemoveRoute(ctx context.Context, appName, routePath string) error {
-	res, err := ds.db.ExecContext(ctx, ds.removeRouteQuery, routePath, appName)
+	query := ds.db.Rebind(`DELETE FROM routes WHERE path = ? AND app_name = ?`)
+	res, err := ds.db.ExecContext(ctx, query, routePath, appName)
 	if err != nil {
 		return err
 	}
@@ -459,7 +431,9 @@ func (ds *sqlStore) RemoveRoute(ctx context.Context, appName, routePath string)
 }
 
 func (ds *sqlStore) GetRoute(ctx context.Context, appName, routePath string) (*models.Route, error) {
-	row := ds.db.QueryRowContext(ctx, ds.getRouteQuery, appName, routePath)
+	rSelectCondition := "%s WHERE app_name=? AND path=?"
+	query := ds.db.Rebind(fmt.Sprintf(rSelectCondition, routeSelector))
+	row := ds.db.QueryRowContext(ctx, query, appName, routePath)
 
 	var route models.Route
 	err := scanRoute(row, &route)
@@ -475,7 +449,8 @@ func (ds *sqlStore) GetRoute(ctx context.Context, appName, routePath string) (*m
 func (ds *sqlStore) GetRoutes(ctx context.Context, filter *models.RouteFilter) ([]*models.Route, error) {
 	res := []*models.Route{}
 	query, args := buildFilterRouteQuery(filter)
-	query = ds.db.Rebind(fmt.Sprintf("%s %s", routeSelector, query))
+	query = fmt.Sprintf("%s %s", routeSelector, query)
+	query = ds.db.Rebind(query)
 	rows, err := ds.db.QueryContext(ctx, query, args...)
 	// todo: check for no rows so we don't respond with a sql 500 err
 	if err != nil {
@@ -552,7 +527,18 @@ func (ds *sqlStore) Tx(f func(*sqlx.Tx) error) error {
 }
 
 func (ds *sqlStore) InsertCall(ctx context.Context, call *models.Call) error {
-	_, err := ds.db.ExecContext(ctx, ds.insertCallQuery, call.ID, call.CreatedAt.String(),
+	query := ds.db.Rebind(`INSERT INTO calls (
+		id,
+		created_at,
+		started_at,
+		completed_at,
+		status,
+		app_name,
+		path
+	)
+	VALUES (?, ?, ?, ?, ?, ?, ?);`)
+
+	_, err := ds.db.ExecContext(ctx, query, call.ID, call.CreatedAt.String(),
 		call.StartedAt.String(), call.CompletedAt.String(),
 		call.Status, call.AppName, call.Path)
 	if err != nil {
@@ -566,7 +552,9 @@ func (ds *sqlStore) InsertCall(ctx context.Context, call *models.Call) error {
 // if we store the whole thing then it adds a lot of disk space and then we can
 // make async only queue hints instead of entire calls (mq a lot smaller space wise). pick.
 func (ds *sqlStore) GetCall(ctx context.Context, appName, callID string) (*models.Call, error) {
-	row := ds.db.QueryRowContext(ctx, ds.getCallQuery, callID, appName)
+	query := fmt.Sprintf(`%s WHERE id=? AND app_name=?`, callSelector)
+	query = ds.db.Rebind(query)
+	row := ds.db.QueryRowContext(ctx, query, callID, appName)
 
 	var call models.Call
 	err := scanCall(row, &call)
@@ -602,12 +590,14 @@ func (ds *sqlStore) GetCalls(ctx context.Context, filter *models.CallFilter) ([]
 }
 
 func (ds *sqlStore) InsertLog(ctx context.Context, callID, callLog string) error {
-	_, err := ds.db.ExecContext(ctx, ds.insertLogQuery, callID, callLog)
+	query := ds.db.Rebind(`INSERT INTO logs (id, log) VALUES (?, ?);`)
+	_, err := ds.db.ExecContext(ctx, query, callID, callLog)
 	return err
 }
 
 func (ds *sqlStore) GetLog(ctx context.Context, callID string) (*models.CallLog, error) {
-	row := ds.db.QueryRowContext(ctx, ds.getLogQuery, callID)
+	query := ds.db.Rebind(`SELECT log FROM logs WHERE id=?`)
+	row := ds.db.QueryRowContext(ctx, query, callID)
 
 	var log string
 	err := row.Scan(&log)
@@ -625,7 +615,8 @@ func (ds *sqlStore) GetLog(ctx context.Context, callID string) (*models.CallLog,
 }
 
 func (ds *sqlStore) DeleteLog(ctx context.Context, callID string) error {
-	_, err := ds.db.ExecContext(ctx, ds.deleteLogQuery, callID)
+	query := ds.db.Rebind(`DELETE FROM logs WHERE id=?`)
+	_, err := ds.db.ExecContext(ctx, query, callID)
 	return err
 }