| // 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 command |
| |
| import ( |
| "context" |
| |
| "github.com/mongodb/mongo-go-driver/bson" |
| "github.com/mongodb/mongo-go-driver/mongo/readconcern" |
| "github.com/mongodb/mongo-go-driver/mongo/readpref" |
| "github.com/mongodb/mongo-go-driver/x/bsonx" |
| "github.com/mongodb/mongo-go-driver/x/mongo/driver/session" |
| "github.com/mongodb/mongo-go-driver/x/network/description" |
| "github.com/mongodb/mongo-go-driver/x/network/wiremessage" |
| ) |
| |
| // Find represents the find command. |
| // |
| // The find command finds documents within a collection that match a filter. |
| type Find struct { |
| NS Namespace |
| Filter bsonx.Doc |
| CursorOpts []bsonx.Elem |
| Opts []bsonx.Elem |
| ReadPref *readpref.ReadPref |
| ReadConcern *readconcern.ReadConcern |
| Clock *session.ClusterClock |
| Session *session.Client |
| |
| result bson.Raw |
| err error |
| } |
| |
| // Encode will encode this command into a wire message for the given server description. |
| func (f *Find) Encode(desc description.SelectedServer) (wiremessage.WireMessage, error) { |
| cmd, err := f.encode(desc) |
| if err != nil { |
| return nil, err |
| } |
| |
| return cmd.Encode(desc) |
| } |
| |
| func (f *Find) encode(desc description.SelectedServer) (*Read, error) { |
| if err := f.NS.Validate(); err != nil { |
| return nil, err |
| } |
| |
| command := bsonx.Doc{{"find", bsonx.String(f.NS.Collection)}} |
| |
| if f.Filter != nil { |
| command = append(command, bsonx.Elem{"filter", bsonx.Document(f.Filter)}) |
| } |
| |
| command = append(command, f.Opts...) |
| |
| return &Read{ |
| Clock: f.Clock, |
| DB: f.NS.DB, |
| ReadPref: f.ReadPref, |
| Command: command, |
| ReadConcern: f.ReadConcern, |
| Session: f.Session, |
| }, nil |
| } |
| |
| // Decode will decode the wire message using the provided server description. Errors during decoding |
| // are deferred until either the Result or Err methods are called. |
| func (f *Find) Decode(desc description.SelectedServer, wm wiremessage.WireMessage) *Find { |
| rdr, err := (&Read{}).Decode(desc, wm).Result() |
| if err != nil { |
| f.err = err |
| return f |
| } |
| |
| return f.decode(desc, rdr) |
| } |
| |
| func (f *Find) decode(desc description.SelectedServer, rdr bson.Raw) *Find { |
| f.result = rdr |
| return f |
| } |
| |
| // Result returns the result of a decoded wire message and server description. |
| func (f *Find) Result() (bson.Raw, error) { |
| if f.err != nil { |
| return nil, f.err |
| } |
| |
| return f.result, nil |
| } |
| |
| // Err returns the error set on this command. |
| func (f *Find) Err() error { return f.err } |
| |
| // RoundTrip handles the execution of this command using the provided wiremessage.ReadWriter. |
| func (f *Find) RoundTrip(ctx context.Context, desc description.SelectedServer, rw wiremessage.ReadWriter) (bson.Raw, error) { |
| cmd, err := f.encode(desc) |
| if err != nil { |
| return nil, err |
| } |
| |
| rdr, err := cmd.RoundTrip(ctx, desc, rw) |
| if err != nil { |
| return nil, err |
| } |
| |
| return f.decode(desc, rdr).Result() |
| } |