| // 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" |
| "fmt" |
| |
| "github.com/mongodb/mongo-go-driver/bson" |
| "github.com/mongodb/mongo-go-driver/x/bsonx" |
| "github.com/mongodb/mongo-go-driver/x/bsonx/bsoncore" |
| "github.com/mongodb/mongo-go-driver/x/network/result" |
| "github.com/mongodb/mongo-go-driver/x/network/wiremessage" |
| ) |
| |
| // IsMaster represents the isMaster command. |
| // |
| // The isMaster command is used for setting up a connection to MongoDB and |
| // for monitoring a MongoDB server. |
| // |
| // Since IsMaster can only be run on a connection, there is no Dispatch method. |
| type IsMaster struct { |
| Client bsonx.Doc |
| Compressors []string |
| SaslSupportedMechs string |
| |
| err error |
| res result.IsMaster |
| } |
| |
| // Encode will encode this command into a wire message for the given server description. |
| func (im *IsMaster) Encode() (wiremessage.WireMessage, error) { |
| cmd := bsonx.Doc{{"isMaster", bsonx.Int32(1)}} |
| if im.Client != nil { |
| cmd = append(cmd, bsonx.Elem{"client", bsonx.Document(im.Client)}) |
| } |
| if im.SaslSupportedMechs != "" { |
| cmd = append(cmd, bsonx.Elem{"saslSupportedMechs", bsonx.String(im.SaslSupportedMechs)}) |
| } |
| |
| // always send compressors even if empty slice |
| array := bsonx.Arr{} |
| for _, compressor := range im.Compressors { |
| array = append(array, bsonx.String(compressor)) |
| } |
| |
| cmd = append(cmd, bsonx.Elem{"compression", bsonx.Array(array)}) |
| |
| rdr, err := cmd.MarshalBSON() |
| if err != nil { |
| return nil, err |
| } |
| query := wiremessage.Query{ |
| MsgHeader: wiremessage.Header{RequestID: wiremessage.NextRequestID()}, |
| FullCollectionName: "admin.$cmd", |
| Flags: wiremessage.SlaveOK, |
| NumberToReturn: -1, |
| Query: rdr, |
| } |
| return query, 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 (im *IsMaster) Decode(wm wiremessage.WireMessage) *IsMaster { |
| reply, ok := wm.(wiremessage.Reply) |
| if !ok { |
| im.err = fmt.Errorf("unsupported response wiremessage type %T", wm) |
| return im |
| } |
| rdr, err := decodeCommandOpReply(reply) |
| if err != nil { |
| im.err = err |
| return im |
| } |
| err = bson.Unmarshal(rdr, &im.res) |
| if err != nil { |
| im.err = err |
| return im |
| } |
| |
| // Reconstructs the $clusterTime doc after decode |
| if im.res.ClusterTime != nil { |
| im.res.ClusterTime = bsoncore.BuildDocument(nil, bsoncore.AppendDocumentElement(nil, "$clusterTime", im.res.ClusterTime)) |
| } |
| return im |
| } |
| |
| // Result returns the result of a decoded wire message and server description. |
| func (im *IsMaster) Result() (result.IsMaster, error) { |
| if im.err != nil { |
| return result.IsMaster{}, im.err |
| } |
| |
| return im.res, nil |
| } |
| |
| // Err returns the error set on this command. |
| func (im *IsMaster) Err() error { return im.err } |
| |
| // RoundTrip handles the execution of this command using the provided wiremessage.ReadWriter. |
| func (im *IsMaster) RoundTrip(ctx context.Context, rw wiremessage.ReadWriter) (result.IsMaster, error) { |
| wm, err := im.Encode() |
| if err != nil { |
| return result.IsMaster{}, err |
| } |
| |
| err = rw.WriteWireMessage(ctx, wm) |
| if err != nil { |
| return result.IsMaster{}, err |
| } |
| wm, err = rw.ReadWireMessage(ctx) |
| if err != nil { |
| return result.IsMaster{}, err |
| } |
| return im.Decode(wm).Result() |
| } |