mongodb nodejs 驱动事务

Question

在书籍集合中插入数据时，我强行在代码中出错，以便我可以检查事务在 mongodb 节点驱动程序中是否正常工作，但是当我运行此代码时，没有发生回滚。 它在用户集合中创建一个文档，然后抛出错误但中止不起作用。

const MongoClient = require( 'mongodb' ).MongoClient;
const URL = "mongodb://localhost:27017/testapp"

MongoClient.connect( URL, {
    useNewUrlParser: true,
    useUnifiedTopology: true
} )
.then( async client => {
    _client = client
    let _db = client.db( 'testapp' );
    let session = _client.startSession()
    session.startTransaction()

    try {
        let info = await _db.collection( 'user' ).insertOne( {
            name: "Anik",
            position: "Full Stack"
        } )

        await _db.collection( 'book' ).insertOne( {
            user_id: info.ops[ 0 ]._id,
            booked: true,
            asdf
        } )

        await session.commitTransaction()
        session.endSession()
        _client.close()

    } catch ( e ) {
        await session.abortTransaction()
        session.endSession()
        _client.close()
        console.log( e.message )
    }
} )
.catch( err => {
    console.log( err )
} )

Answer 1

1. 您需要一个复制集来使用 mongodb 的事务
2. 您需要在所有写入操作的选项中路径session

const MongoClient = require( 'mongodb' ).MongoClient;
const URL = "mongodb://localhost:27017/testapp?rs=myreplicaset"

MongoClient.connect( URL, {
    useNewUrlParser: true,
    useUnifiedTopology: true
} )
.then( async client => {
    let db = client.db( 'testapp' );
    let session = client.startSession()
    session.startTransaction()

    try {
        let info = await db.collection( 'user' ).insertOne( {
            name: "Anik",
            position: "Full Stack"
        } , {session})

        await db.collection( 'book' ).insertOne( {
            user_id: info.ops[ 0 ]._id,
            booked: true,
            asdf
        } , {session})

        await session.commitTransaction()

    } catch ( e ) {
        await session.abortTransaction()
        console.log( e.message )
    } finally {
        session.endSession()
        client.close()
    }
} )
.catch( err => {
    console.log( err )
} )