fix: now dsl.Execute() rolls back when error occurred

And now TrxIDKey is not included in context.

Author: tyru

dsl/dslctx/dslctx.go

@@ -0,0 +1,64 @@
+package dslctx
+
+import (
+	"context"
+	"errors"
+
+	"github.com/vim-volt/volt/config"
+	"github.com/vim-volt/volt/lockjson"
+)
+
+// KeyType is the type of the key of context specified for Execute()
+type KeyType uint
+
+const (
+	// TrxIDKey is the key to get transaction ID
+	TrxIDKey KeyType = iota
+	// LockJSONKey is the key to get *lockjson.LockJSON value
+	LockJSONKey
+	// ConfigKey is the key to get *config.Config value
+	ConfigKey
+)
+
+// WithDSLValues adds given values
+func WithDSLValues(ctx context.Context, lockJSON *lockjson.LockJSON, cfg *config.Config) context.Context {
+	ctx = context.WithValue(ctx, LockJSONKey, lockJSON)
+	ctx = context.WithValue(ctx, ConfigKey, cfg)
+	return ctx
+}
+
+// Validate validates if required keys exist in ctx
+func Validate(ctx context.Context) error {
+	for _, required := range []struct {
+		key      KeyType
+		validate func(interface{}) error
+	}{
+		{LockJSONKey, validateLockJSON},
+		{ConfigKey, validateConfig},
+	} {
+		if err := required.validate(ctx.Value(required.key)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func validateLockJSON(v interface{}) error {
+	if v == nil {
+		return errors.New("no lock.json key in context")
+	}
+	if _, ok := v.(*lockjson.LockJSON); !ok {
+		return errors.New("invalid lock.json data in context")
+	}
+	return nil
+}
+
+func validateConfig(v interface{}) error {
+	if v == nil {
+		return errors.New("no config.toml key in context")
+	}
+	if _, ok := v.(*config.Config); !ok {
+		return errors.New("invalid config.toml data in context")
+	}
+	return nil
+}

dsl/execute.go

@@ -4,68 +4,32 @@ import (
 	"context"
 
 	"github.com/pkg/errors"
-	"github.com/vim-volt/volt/config"
-	"github.com/vim-volt/volt/dsl/ops"
+	"github.com/vim-volt/volt/dsl/dslctx"
 	"github.com/vim-volt/volt/dsl/types"
-	"github.com/vim-volt/volt/lockjson"
 	"github.com/vim-volt/volt/transaction"
 )
 
-// CtxKeyType is the type of the key of context specified for Execute()
-type CtxKeyType uint
-
-const (
-	// CtxTrxIDKey is the key to get transaction ID
-	CtxTrxIDKey CtxKeyType = iota
-	// CtxLockJSONKey is the key to get *lockjson.LockJSON value
-	CtxLockJSONKey
-	// CtxConfigKey is the key to get *config.Config value
-	CtxConfigKey
-)
-
 // Execute executes given expr with given ctx.
-func Execute(ctx context.Context, expr types.Expr) (val types.Value, rollback func(), err error) {
-	for _, required := range []struct {
-		key      CtxKeyType
-		validate func(interface{}) error
-	}{
-		{CtxLockJSONKey, validateLockJSON},
-		{CtxConfigKey, validateConfig},
-		{CtxTrxIDKey, validateTrxID},
-	} {
-		if err := required.validate(ctx.Value(required.key)); err != nil {
-			return nil, ops.NoRollback, err
-		}
+func Execute(ctx context.Context, expr types.Expr) (_ types.Value, result error) {
+	if err := dslctx.Validate(ctx); err != nil {
+		return nil, err
 	}
-	return expr.Eval(ctx)
-}
 
-func validateLockJSON(v interface{}) error {
-	if v == nil {
-		return errors.New("no lock.json key in context")
-	}
-	if _, ok := v.(*lockjson.LockJSON); !ok {
-		return errors.New("invalid lock.json data in context")
+	// Begin transaction
+	trx, err := transaction.Start()
+	if err != nil {
+		return nil, err
 	}
-	return nil
-}
-
-func validateConfig(v interface{}) error {
-	if v == nil {
-		return errors.New("no config.toml key in context")
-	}
-	if _, ok := v.(*config.Config); !ok {
-		return errors.New("invalid config.toml data in context")
-	}
-	return nil
-}
+	defer func() {
+		if err := trx.Done(); err != nil {
+			result = err
+		}
+	}()
 
-func validateTrxID(v interface{}) error {
-	if v == nil {
-		return errors.New("no transaction ID key in context")
-	}
-	if _, ok := v.(transaction.TrxID); !ok {
-		return errors.New("invalid transaction ID data in context")
+	val, rollback, err := expr.Eval(ctx)
+	if err != nil {
+		rollback()
+		return nil, errors.Wrap(err, "expression returned an error")
 	}
-	return nil
+	return val, nil
 }