Mongo DB in c#: Transaction not working - what I'm doing wrong?-CodePudding

I have a situation like this:

var mongoClient = new MongoClient("connection-bla-bla");
var mongoDB = mongoClient.GetDatabase("db-name");
using (var session = mongoDB.Client.StartSession())
{
    session.StartTransaction();
    var collection = mongoDB.GetCollection<Rec>("collectionName");
    collection.InsertOne(new Rec() { Name = "Record1" });
    collection.InsertOne(new Rec() { Name = "Record2" });
    session.CommitTransaction();
}

This code works quite fine, Record1 and Record2 are written.

However, when i try this ...

var mongoClient = new MongoClient("connection-bla-bla");
var mongoDB = mongoClient.GetDatabase("db-name");
using (var session = mongoDB.Client.StartSession())
{
    session.StartTransaction();
    var collection = mongoDB.GetCollection<Rec>("collectionName");
    collection.InsertOne(new Rec() { Name = "Record1" });
    if (DateTime.UtcNow > DateTime.MinValue) throw new Exception("Bad things happens");
    collection.InsertOne(new Rec() { Name = "Record2" });
    session.CommitTransaction();
}

... Record1 is written, even the transaction is not comitted. I guess I miss here something, but have no clue what. Thanks for code correction.

CodePudding user response：

In order to use the transaction, you need to specify the session when calling the insert commands:

var mongoClient = new MongoClient("connection-bla-bla");
var mongoDB = mongoClient.GetDatabase("db-name");
using (var session = mongoDB.Client.StartSession())
{
    session.StartTransaction();
    var collection = mongoDB.GetCollection<Rec>("collectionName");
    collection.InsertOne(session, new Rec() { Name = "Record1" });
    if (DateTime.UtcNow > DateTime.MinValue) throw new Exception("Bad things happens");
    collection.InsertOne(session, new Rec() { Name = "Record2" });
    session.CommitTransaction();
}

There are overloads for various write commands that accept the session. See this link for details.