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author | Mura Li <typeless@users.noreply.github.com> | 2019-03-27 19:15:23 +0800 |
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committer | Lunny Xiao <xiaolunwen@gmail.com> | 2019-03-27 19:15:23 +0800 |
commit | d77176912bccf1dc0ad93366df55f00fee23b498 (patch) | |
tree | 309fc6350f77f4061360160b88343360d45d5d24 /vendor/google.golang.org/appengine/internal/transaction.go | |
parent | d578b71d61ee8131e8abf7f538b93d8c6cc6fe6d (diff) | |
download | gitea-d77176912bccf1dc0ad93366df55f00fee23b498.tar.gz gitea-d77176912bccf1dc0ad93366df55f00fee23b498.zip |
Use Go1.11 module (#5743)
* Migrate to go modules
* make vendor
* Update mvdan.cc/xurls
* make vendor
* Update code.gitea.io/git
* make fmt-check
* Update github.com/go-sql-driver/mysql
* make vendor
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, 115 insertions, 0 deletions
diff --git a/vendor/google.golang.org/appengine/internal/transaction.go b/vendor/google.golang.org/appengine/internal/transaction.go new file mode 100644 index 0000000000..9006ae6538 --- /dev/null +++ b/vendor/google.golang.org/appengine/internal/transaction.go @@ -0,0 +1,115 @@ +// 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 +} |