Prisma with CosmosDB, MongoDB connector has error for sharded collections

Discussed in https://github.com/prisma/prisma/discussions/9544

<div type='discussions-op-text'>

^{Originally posted by dohaicuong October 1, 2021} Hi Prisma Team! I just got this error when setup Prisma with MongoDB on Azure CosmosDB and create a sharded collection

Invalid `prisma.user.create()` invocation:\n\n\n  Error occurred during query execution:\nConnectorError(ConnectorError {
user_facing_error: None, kind: RawError { 
code: \"unknown\", message: \"Command failed (50841): Multi-document transactions cannot be run in a sharded collection)\" 
} })

Versions

• Node: v14.17.4
• OS: macOs
• Prisma client: 3.1.1
• Database: MongoDB 4.0 on Azure CosmosDB

Schema

datasource db {
  provider = "mongodb"
  url      = env("DATABASE_URL")
}

generator client {
  provider        = "prisma-client-js"
  previewFeatures = ["mongoDb"]
}

model User {
  id String @id @default(dbgenerated()) @map("_id") @db.ObjectId
  name String
}

MongoDB setup

• Create mongoDB 4.0 on cosmosDB
• Create new DB and User collection with shard key

Connection string

mongodb://user:pass@url/db_name?ssl=true
&connectTimeoutMS=5000
&maxPoolSize=50
&replicaSet=globaldb
&retrywrites=false
&maxIdleTimeMS=120000
&appName=@app_name@

Prisma command

const newUser = await prisma.user.create({
  data: { name: 'name' }
})

Errors

Invalid `prisma.user.create()` invocation:\n\n\n  Error occurred during query execution:\nConnectorError(ConnectorError { user_facing_error: None, kind: RawError { code: \"unknown\", message: \"Command failed (50841): Multi-document transactions cannot be run in a sharded collection)\" } })
```</div>

[janpio]

Unfortunately the MongoDB API of Azure CosmosDB is stuck at version 4.0: https://docs.microsoft.com/en-us/azure/cosmos-db/mongodb/mongodb-introduction#how-the-api-works @matthewmueller - but this problem is CosmosDB specific, not caused by MongoDB 4.0 (see below)

---

I can now also reproduce a close error with a simple CosmosDB with MongoDB 4.0 API via the CosmosDB Emulator:

$ ts-node ./script.ts
PrismaClientUnknownRequestError: 
Invalid `client.user.create()` invocation in
D:\a\e2e-tests\e2e-tests\databases-windows\mongodb-azure-cosmosdb-emulator\script.ts:9:21

   6 async function main() {
   7 
   8   // On CosmosDB the first delete will fail if you do not make sure the database and collection actually exist, so creating so dummy data first
→  9   await client.user.create(
  Error occurred during query execution:
ConnectorError(ConnectorError { user_facing_error: None, kind: RawDatabaseError { code: "unknown", message: "Command failed (OperationNotSupportedInTransaction): Command insert failed : can not create collection in a multi-document transaction)" } })
    at cb (D:\a\e2e-tests\e2e-tests\databases-windows\mongodb-azure-cosmosdb-emulator\node_modules\@prisma\client\runtime\index.js:39807:17) {
  clientVersion: '3.10.0-dev.54'
}

Knowing these concepts now, I could also find the documention on the CosmosDB side for this:

Transactions Multi-document transactions are supported within an unsharded collection. Multi-document transactions are not supported across collections or in sharded collections. The timeout for transactions is a fixed 5 seconds.

https://docs.microsoft.com/en-us/azure/cosmos-db/mongodb/feature-support-40#transactions

So:

• Prisma is using “multi-document transactions” by default to create a new collection.
• CosmosDB MongoDB does not support that for “across collections or in sharded collections”.

---

The exact error you got @dohaicuong I indeed only get when I create a collection via the web UI and explicitly enable sharing on it:

$ ts-node ./script.ts
success
PrismaClientUnknownRequestError: 
Invalid `client.test.create()` invocation in
/home/runner/work/e2e-tests/e2e-tests/databases/mongodb-azure-cosmosdb/script.ts:38:21

  35 
  36 console.log('success')
  37 
→ 38 await client.test.create(
  Error occurred during query execution:
ConnectorError(ConnectorError { user_facing_error: None, kind: RawDatabaseError { code: "unknown", message: "Command failed (50841): Multi-document transactions cannot be run in a sharded collection)" } })
    at cb (/home/runner/work/e2e-tests/e2e-tests/databases/mongodb-azure-cosmosdb/node_modules/@prisma/client/runtime/index.js:39807:17) {
  clientVersion: '3.10.0-dev.66'
}

I assume that is also what you did?

[janpio]

Side note: We also do not know yet if we support Shard Clusters of normal MongoDB: https://github.com/prisma/prisma/issues/12380