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Diffstat (limited to 'vendor/google.golang.org/appengine/internal/transaction.go')
-rw-r--r-- | vendor/google.golang.org/appengine/internal/transaction.go | 115 |
1 files changed, 0 insertions, 115 deletions
diff --git a/vendor/google.golang.org/appengine/internal/transaction.go b/vendor/google.golang.org/appengine/internal/transaction.go deleted file mode 100644 index 9006ae653..000000000 --- a/vendor/google.golang.org/appengine/internal/transaction.go +++ /dev/null @@ -1,115 +0,0 @@ -// Copyright 2014 Google Inc. All rights reserved. -// Use of this source code is governed by the Apache 2.0 -// license that can be found in the LICENSE file. - -package internal - -// This file implements hooks for applying datastore transactions. - -import ( - "errors" - "reflect" - - "github.com/golang/protobuf/proto" - netcontext "golang.org/x/net/context" - - basepb "google.golang.org/appengine/internal/base" - pb "google.golang.org/appengine/internal/datastore" -) - -var transactionSetters = make(map[reflect.Type]reflect.Value) - -// RegisterTransactionSetter registers a function that sets transaction information -// in a protocol buffer message. f should be a function with two arguments, -// the first being a protocol buffer type, and the second being *datastore.Transaction. -func RegisterTransactionSetter(f interface{}) { - v := reflect.ValueOf(f) - transactionSetters[v.Type().In(0)] = v -} - -// applyTransaction applies the transaction t to message pb -// by using the relevant setter passed to RegisterTransactionSetter. -func applyTransaction(pb proto.Message, t *pb.Transaction) { - v := reflect.ValueOf(pb) - if f, ok := transactionSetters[v.Type()]; ok { - f.Call([]reflect.Value{v, reflect.ValueOf(t)}) - } -} - -var transactionKey = "used for *Transaction" - -func transactionFromContext(ctx netcontext.Context) *transaction { - t, _ := ctx.Value(&transactionKey).(*transaction) - return t -} - -func withTransaction(ctx netcontext.Context, t *transaction) netcontext.Context { - return netcontext.WithValue(ctx, &transactionKey, t) -} - -type transaction struct { - transaction pb.Transaction - finished bool -} - -var ErrConcurrentTransaction = errors.New("internal: concurrent transaction") - -func RunTransactionOnce(c netcontext.Context, f func(netcontext.Context) error, xg bool, readOnly bool, previousTransaction *pb.Transaction) (*pb.Transaction, error) { - if transactionFromContext(c) != nil { - return nil, errors.New("nested transactions are not supported") - } - - // Begin the transaction. - t := &transaction{} - req := &pb.BeginTransactionRequest{ - App: proto.String(FullyQualifiedAppID(c)), - } - if xg { - req.AllowMultipleEg = proto.Bool(true) - } - if previousTransaction != nil { - req.PreviousTransaction = previousTransaction - } - if readOnly { - req.Mode = pb.BeginTransactionRequest_READ_ONLY.Enum() - } else { - req.Mode = pb.BeginTransactionRequest_READ_WRITE.Enum() - } - if err := Call(c, "datastore_v3", "BeginTransaction", req, &t.transaction); err != nil { - return nil, err - } - - // Call f, rolling back the transaction if f returns a non-nil error, or panics. - // The panic is not recovered. - defer func() { - if t.finished { - return - } - t.finished = true - // Ignore the error return value, since we are already returning a non-nil - // error (or we're panicking). - Call(c, "datastore_v3", "Rollback", &t.transaction, &basepb.VoidProto{}) - }() - if err := f(withTransaction(c, t)); err != nil { - return &t.transaction, err - } - t.finished = true - - // Commit the transaction. - res := &pb.CommitResponse{} - err := Call(c, "datastore_v3", "Commit", &t.transaction, res) - if ae, ok := err.(*APIError); ok { - /* TODO: restore this conditional - if appengine.IsDevAppServer() { - */ - // The Python Dev AppServer raises an ApplicationError with error code 2 (which is - // Error.CONCURRENT_TRANSACTION) and message "Concurrency exception.". - if ae.Code == int32(pb.Error_BAD_REQUEST) && ae.Detail == "ApplicationError: 2 Concurrency exception." { - return &t.transaction, ErrConcurrentTransaction - } - if ae.Code == int32(pb.Error_CONCURRENT_TRANSACTION) { - return &t.transaction, ErrConcurrentTransaction - } - } - return &t.transaction, err -} |