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82 lines
3.1 KiB
Go
82 lines
3.1 KiB
Go
// Copyright (C) MongoDB, Inc. 2017-present.
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//
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// Licensed under the Apache License, Version 2.0 (the "License"); you may
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// not use this file except in compliance with the License. You may obtain
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// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
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// NOTE: This documentation should be kept in line with the Example* test functions.
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// Package mongo provides a MongoDB Driver API for Go.
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//
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// Basic usage of the driver starts with creating a Client from a connection
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// string. To do so, call the NewClient and Connect functions:
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//
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// client, err := NewClient(options.Client().ApplyURI("mongodb://foo:bar@localhost:27017"))
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// if err != nil { return err }
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// ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
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// defer cancel()
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// err = client.Connect(ctx)
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// if err != nil { return err }
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//
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// This will create a new client and start monitoring the MongoDB server on localhost.
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// The Database and Collection types can be used to access the database:
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//
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// collection := client.Database("baz").Collection("qux")
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//
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// A Collection can be used to query the database or insert documents:
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//
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// res, err := collection.InsertOne(context.Background(), bson.M{"hello": "world"})
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// if err != nil { return err }
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// id := res.InsertedID
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//
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// Several methods return a cursor, which can be used like this:
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//
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// cur, err := collection.Find(context.Background(), bson.D{})
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// if err != nil { log.Fatal(err) }
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// defer cur.Close(context.Background())
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// for cur.Next(context.Background()) {
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// // To decode into a struct, use cursor.Decode()
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// result := struct{
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// Foo string
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// Bar int32
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// }{}
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// err := cur.Decode(&result)
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// if err != nil { log.Fatal(err) }
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// // do something with result...
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//
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// // To get the raw bson bytes use cursor.Current
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// raw := cur.Current
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// // do something with raw...
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// }
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// if err := cur.Err(); err != nil {
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// return err
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// }
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//
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// Methods that only return a single document will return a *SingleResult, which works
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// like a *sql.Row:
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//
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// result := struct{
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// Foo string
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// Bar int32
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// }{}
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// filter := bson.D{{"hello", "world"}}
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// err := collection.FindOne(context.Background(), filter).Decode(&result)
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// if err != nil { return err }
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// // do something with result...
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//
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// All Client, Collection, and Database methods that take parameters of type interface{}
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// will return ErrNilDocument if nil is passed in for an interface{}.
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//
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// Additional examples can be found under the examples directory in the driver's repository and
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// on the MongoDB website.
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//
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// Potential DNS Issues
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//
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// Building with Go 1.11+ and using connection strings with the "mongodb+srv"[1] scheme is
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// incompatible with some DNS servers in the wild due to the change introduced in
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// https://github.com/golang/go/issues/10622. If you receive an error with the message "cannot
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// unmarshal DNS message" while running an operation, we suggest you use a different DNS server.
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//
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// [1] See https://docs.mongodb.com/manual/reference/connection-string/#dns-seedlist-connection-format
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package mongo
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