Ufdjrw

I have several bots accessing a CosmosDB. They get a userId through an URL parameter from the client.

My problem appears when using the same bot in different instances at the same time.

Let's say I start a conversation with the userID "1", enter some data like name, age, gender. In the middle of the conversation, I open up another website with the userID "2". User 2 enters name. User 1 finishes profile creation. User 2 is prompted for age. Suddenly, the userID from User 2 changes to "1" and the profile data is identical to the userdata from user 1.

From time to time, I get the following error:

 code: 412,
body: ‘“code”:“PreconditionFailed”,“message”:“Operation cannot be performed because one of the specified precondition is not met., rnRequestStartTime: 2019-03-07T20:57:19.6998897Z, RequestEndTime: 2019-03-07T20:57:19.7098745Z, Number of regions attempted: 1rnResponseTime: 2019-03-07T20:57:19.7098745Z, StoreResult: StorePhysicalAddress: rntbd://cdb-ms-prod-westeurope1-fd21.documents.azure.com:16817/apps/9bc5d0cc-9b7c-4b1d-9be2-0fa2654271c4/services/3507a423-5215-48ca-995a-8763ec527db8/partitions/940cd512-aa34-4c93-9596-743de41037da/replicas/131964420031154286p/, LSN: 172, GlobalCommittedLsn: 171, PartitionKeyRangeId: 0, IsValid: True, StatusCode: 412, SubStatusCode: 0, RequestCharge: 1.24, ItemLSN: -1, SessionToken: 172, UsingLocalLSN: False, TransportException: null, ResourceType: Document, OperationType: Replacern, Microsoft.Azure.Documents.Common/2.2.0.0”’,
activityId: ‘fbdaeedb-a73f-4052-bd55-b1417b10583f’ 

So, the bot seems to mix up the userIDs in some way.

I save UserState and ConversationState in a local storage, since I don't need them saved in my DB:

// Local browser storage
const memoryStorageLocal = new MemoryStorage();

// ConversationState and UserState
const conversationState = new ConversationState(memoryStorageLocal);
const userState = new UserState(memoryStorageLocal);

I obtain the userID as follows, which equals the URL param

for (var idx in turnContext.activity.membersAdded) 
 if (turnContext.activity.membersAdded[idx].id !== turnContext.activity.recipient.id) 
 console.log("User added");
 this.userID = turnContext.activity.membersAdded[idx].id;
 

I read and write to the DB as follows:

// Read userData object
try 
 user = await this.memoryStorage.read([this.userID]);
 console.log("User Object read from DB: " + util.inspect(user, false, null, true /* enable colors */));

catch(e) 
 console.log("Reading user data failed");
 console.log(e);


// If user is new, create UserData object and save it to DB and read it for further use
if(isEmpty(user)) 
 await step.context.sendActivity("New User Detected");
 this.changes[this.userID] = this.userData;
 await this.memoryStorage.write(this.changes);
 user = await this.memoryStorage.read([this.userID]);

This is the "empty" userData object I save to the DB if the user is new:

this.userData = 

 name: "",
 age: "",
 gender: "",
 education: "",
 major: "",

 riskData: 
 roundCounter: "",
 riskAssessmentComplete: "",
 riskDescription: "",
 repeat: "",
 choices: "",
 ,

 investData: 
 repeat: "",
 order: "",
 choice: "",
 follow: "",
 win1: "",
 win2: "",
 loss1: "",
 loss2: "",
 ,

 endRepeat: "",
 eTag: '*',
 

To me it seems like the actual problem is not how I read and write from and to the CosmosDB, but that there aren't different instances of the bot as the user IDs and userdata gets mixed up when using them simultaneously.

How can I make this work? You can find my bot code here:

https://github.com/FRANZKAFKA13/roboadvisoryBot

Thanks in advance for any help!

It's because you're storing everything in your constructor, which is only called by the bot once. The same instances of this.changes and this.userId are being used by both users at the same time. When one user changes it, it also changes for the other user. It's basically making them global variables that any user has the ability to change.

Instead, you can pass the variables you need to the dialogs using step.options.

For example,

Calling the dialog:

await dc.beginDialog('welcome', userId)

Using within the dialog:

this.userId = step.options // It may also be step.options.userId, if you pass it in as part of a larger object, like .beginDialog('welcome', userId: '123', userName: 'xyz' )

Note

Regarding the way you originally tried this, by instantiating this.userId in the constructor:

You can actually get away with this in C#, since in the C# SDK, the constructor is called on every message (JS/TS it is only called when the bot is first initiated). This major difference exists between BotFramework's JS and C# SDKs because C# is multi-threaded and JS is single-threaded. By calling the constructor on each message in C#, you can spread the load across threads. This isn't possible in JS/TS.

That being said, I would still avoid this as it's better code practice not to use "global" variables when possible.