diff options
Diffstat (limited to 'src/mongo/gotools/src/github.com/mongodb/mongo-tools/vendor/go.mongodb.org/mongo-driver/mongo/cursor.go')
| -rw-r--r-- | src/mongo/gotools/src/github.com/mongodb/mongo-tools/vendor/go.mongodb.org/mongo-driver/mongo/cursor.go | 235 |
1 files changed, 0 insertions, 235 deletions
diff --git a/src/mongo/gotools/src/github.com/mongodb/mongo-tools/vendor/go.mongodb.org/mongo-driver/mongo/cursor.go b/src/mongo/gotools/src/github.com/mongodb/mongo-tools/vendor/go.mongodb.org/mongo-driver/mongo/cursor.go deleted file mode 100644 index 37c4452c1dc..00000000000 --- a/src/mongo/gotools/src/github.com/mongodb/mongo-tools/vendor/go.mongodb.org/mongo-driver/mongo/cursor.go +++ /dev/null @@ -1,235 +0,0 @@ -// Copyright (C) MongoDB, Inc. 2017-present. -// -// Licensed under the Apache License, Version 2.0 (the "License"); you may -// not use this file except in compliance with the License. You may obtain -// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 - -package mongo - -import ( - "context" - "errors" - "io" - "reflect" - - "go.mongodb.org/mongo-driver/bson" - "go.mongodb.org/mongo-driver/bson/bsoncodec" - "go.mongodb.org/mongo-driver/x/bsonx/bsoncore" - "go.mongodb.org/mongo-driver/x/mongo/driver" - "go.mongodb.org/mongo-driver/x/mongo/driver/session" -) - -// Cursor is used to iterate a stream of documents. Each document is decoded into the result -// according to the rules of the bson package. -// -// A typical usage of the Cursor type would be: -// -// var cur *Cursor -// ctx := context.Background() -// defer cur.Close(ctx) -// -// for cur.Next(ctx) { -// elem := &bson.D{} -// if err := cur.Decode(elem); err != nil { -// log.Fatal(err) -// } -// -// // do something with elem.... -// } -// -// if err := cur.Err(); err != nil { -// log.Fatal(err) -// } -// -type Cursor struct { - // Current is the BSON bytes of the current document. This property is only valid until the next - // call to Next or Close. If continued access is required to the bson.Raw, you must make a copy - // of it. - Current bson.Raw - - bc batchCursor - batch *bsoncore.DocumentSequence - registry *bsoncodec.Registry - clientSession *session.Client - - err error -} - -func newCursor(bc batchCursor, registry *bsoncodec.Registry) (*Cursor, error) { - return newCursorWithSession(bc, registry, nil) -} - -func newCursorWithSession(bc batchCursor, registry *bsoncodec.Registry, clientSession *session.Client) (*Cursor, error) { - if registry == nil { - registry = bson.DefaultRegistry - } - if bc == nil { - return nil, errors.New("batch cursor must not be nil") - } - c := &Cursor{ - bc: bc, - registry: registry, - clientSession: clientSession, - } - if bc.ID() == 0 { - c.closeImplicitSession() - } - return c, nil -} - -func newEmptyCursor() *Cursor { - return &Cursor{bc: driver.NewEmptyBatchCursor()} -} - -// ID returns the ID of this cursor. -func (c *Cursor) ID() int64 { return c.bc.ID() } - -// Next gets the next result from this cursor. Returns true if there were no errors and the next -// result is available for decoding. -func (c *Cursor) Next(ctx context.Context) bool { - if ctx == nil { - ctx = context.Background() - } - doc, err := c.batch.Next() - switch err { - case nil: - c.Current = bson.Raw(doc) - return true - case io.EOF: // Need to do a getMore - default: - c.err = err - return false - } - - // call the Next method in a loop until at least one document is returned in the next batch or - // the context times out. - for { - // If we don't have a next batch - if !c.bc.Next(ctx) { - // Do we have an error? If so we return false. - c.err = c.bc.Err() - if c.err != nil { - return false - } - // Is the cursor ID zero? - if c.bc.ID() == 0 { - c.closeImplicitSession() - return false - } - // empty batch, but cursor is still valid, so continue. - continue - } - - // close the implicit session if this was the last getMore - if c.bc.ID() == 0 { - c.closeImplicitSession() - } - - c.batch = c.bc.Batch() - doc, err = c.batch.Next() - switch err { - case nil: - c.Current = bson.Raw(doc) - return true - case io.EOF: // Empty batch so we continue - default: - c.err = err - return false - } - } -} - -// Decode will decode the current document into val. If val is nil or is a typed nil, an error will be returned. -func (c *Cursor) Decode(val interface{}) error { - return bson.UnmarshalWithRegistry(c.registry, c.Current, val) -} - -// Err returns the current error. -func (c *Cursor) Err() error { return c.err } - -// Close closes this cursor. -func (c *Cursor) Close(ctx context.Context) error { - defer c.closeImplicitSession() - return c.bc.Close(ctx) -} - -// All iterates the cursor and decodes each document into results. -// The results parameter must be a pointer to a slice. The slice pointed to by results will be completely overwritten. -// If the cursor has been iterated, any previously iterated documents will not be included in results. -// The cursor will be closed after the method has returned. -func (c *Cursor) All(ctx context.Context, results interface{}) error { - resultsVal := reflect.ValueOf(results) - if resultsVal.Kind() != reflect.Ptr { - return errors.New("results argument must be a pointer to a slice") - } - - sliceVal := resultsVal.Elem() - elementType := sliceVal.Type().Elem() - var index int - var err error - - defer c.Close(ctx) - - batch := c.batch // exhaust the current batch before iterating the batch cursor - for { - sliceVal, index, err = c.addFromBatch(sliceVal, elementType, batch, index) - if err != nil { - return err - } - - if !c.bc.Next(ctx) { - break - } - - batch = c.bc.Batch() - } - - if err = c.bc.Err(); err != nil { - return err - } - - resultsVal.Elem().Set(sliceVal.Slice(0, index)) - return nil -} - -// addFromBatch adds all documents from batch to sliceVal starting at the given index. It returns the new slice value, -// the next empty index in the slice, and an error if one occurs. -func (c *Cursor) addFromBatch(sliceVal reflect.Value, elemType reflect.Type, batch *bsoncore.DocumentSequence, - index int) (reflect.Value, int, error) { - - docs, err := batch.Documents() - if err != nil { - return sliceVal, index, err - } - - for _, doc := range docs { - if sliceVal.Len() == index { - // slice is full - newElem := reflect.New(elemType) - sliceVal = reflect.Append(sliceVal, newElem.Elem()) - sliceVal = sliceVal.Slice(0, sliceVal.Cap()) - } - - currElem := sliceVal.Index(index).Addr().Interface() - if err = bson.UnmarshalWithRegistry(c.registry, doc, currElem); err != nil { - return sliceVal, index, err - } - - index++ - } - - return sliceVal, index, nil -} - -func (c *Cursor) closeImplicitSession() { - if c.clientSession != nil && c.clientSession.SessionType == session.Implicit { - c.clientSession.EndSession() - } -} - -// BatchCursorFromCursor returns a driver.BatchCursor for the given Cursor. If there is no underlying driver.BatchCursor, -// nil is returned. This method is deprecated and does not have any stability guarantees. It may be removed in the future. -func BatchCursorFromCursor(c *Cursor) *driver.BatchCursor { - bc, _ := c.bc.(*driver.BatchCursor) - return bc -} |