MongoDB Node.js Driver doesn't work when connecting to MongoDB Atlas from Deno

[alexbevi]

Potentially related to issue #15824, but the mongodb driver cannot be used directly via Deno when targeting a MongoDB Atlas cluster. This was reported at NODE-4782 however it doesn't appear to be an issue with the Node driver itself.

// file: main.ts
import { MongoClient } from "mongodb"

const URI = "mongodb+srv://user:pass@cluster0.abcde.mongodb.net/test"
const client = new MongoClient(URI)

async function main() {
  console.log('connecting')  
  await client.connect()  
  console.log('connected')
  const collection = client.db('test_db').collection('test_collection')
  await collection.deleteMany({})
  await collection.insertOne({ a: 2.3 })
  var results = await collection.count({ a: 2.3 })
  console.log(`found ${results}`)
  process.exit(1)
}

main()

For example, when running the preceding using npx ts-node main.ts the script will connect to Atlas, authenticate/authorize, clear the collection, insert a new doc and execute a count.

connecting
connected
found 1

To make this run with Deno the script was updated as follows:

// file: main.ts
import { MongoClient } from 'npm:mongodb' // updated for Deno

const URI = "mongodb+srv://user:pass@cluster0.abcde.mongodb.net/test"
const client = new MongoClient(URI)

async function main() {
  console.log('connecting')  
  await client.connect()  
  console.log('connected')
  const collection = client.db('test_db').collection('test_collection')
  await collection.deleteMany({})
  await collection.insertOne({ a: 2.3 })
  var results = await collection.count({ a: 2.3 })
  console.log(`found ${results}`)
  process.exit(1)
}

main()

When the above script variation is run using deno run --unstable --allow-all main.ts it will fail with the following error as it doesn't appear to be able to resolve a DNS Seed List Connection String:

connecting
error: Uncaught MongoAPIError: Server record does not share hostname with parent URI
    at resolveSRVRecord (file:///Users/alex/Library/Caches/deno/npm/registry.npmjs.org/mongodb/4.11.0/lib/connection_string.js:62:19)
    at async file:///Users/alex/Library/Caches/deno/npm/registry.npmjs.org/mongodb/4.11.0/lib/mongo_client.js:120:31
    at async main (file:///Users/alex/temp/main.ts:17:3)

Changing the URI constant to use a Standard Connection String of mongodb://user:pass@cluster0-shard-00-00.abcde.mongodb.net:27017,cluster0-shard-00-01.abcde.mongodb.net:27017,cluster0-shard-00-02.abcde.mongodb.net:27017/test?ssl=true&replicaSet=Cluster0-shard-0&authSource=admin&retryWrites=true&w=majority and re-running results in the operation just timing out:

connecting
error: Uncaught MongoServerSelectionError: connection timed out
    at Timeout.<anonymous> (file:///Users/alex/Library/Caches/deno/npm/registry.npmjs.org/mongodb/4.11.0/lib/sdam/topology.js:293:38)
    at https://deno.land/std@0.162.0/node/timers.ts:21:15
    at Object.action (deno:ext/web/02_timers.js:147:13)
    at handleTimerMacrotask (deno:ext/web/02_timers.js:64:12)

Note this was tested with:

deno 1.27.2 (release, x86_64-apple-darwin)
v8 10.8.168.4
typescript 4.8.3

Steps to Reproduce

1. Sign up for a free M0 Atlas Cluster
2. Get a Connection String (pick an older version of any driver to get the mongodb:// version instead of mongodb+srv://)
3. Update the URI constant with your connection string
4. deno run --unstable --allow-all main.ts

[ThePotatoChronicler]

The same error pops up on Linux x86_64 with Deno 1.28.1

[brendantang]

Same issue!

[NovqiGarrix]

Same issue here with Deno v1.28.2

[avalero]

Same on Deno 1.30 and npm MongoDB 5.0.0

[alexbevi]

Note the MongoDB Node.js team has filed NODE-5042 which may address the "MongoAPIError: Server record does not share hostname with parent URI" portion of this issue.

[ImagiNFT]

is there any solution for this?

[alexbevi]

Interesting development. Using a DNS Seed List in the URI appears to work correctly in the latest Deno:

$ deno --version
deno 1.30.3 (release, x86_64-apple-darwin)
v8 10.9.194.5
typescript 4.9.4

// file: main.ts
import { MongoClient } from 'npm:mongodb' // updated for Deno

const URI =
"mongodb://<user>:<pass>@cluster0-shard-00-00.abcde.mongodb.net:27017,cluster0-shard-00-01.abcde.mongodb.net:27017,cluster0-shard-00-02.abcde.mongodb.net:27017/?ssl=true&replicaSet=atlas-122v8z-shard-0&authSource=admin&retryWrites=true&w=majority"
const client = new MongoClient(URI)

async function main() {
  console.log('connecting')
  await client.connect()
  console.log('connected')
  const collection = client.db('test_db').collection('test_collection')
  await collection.deleteMany({})
  await collection.insertOne({ a: 2.3 })
  var results = await collection.count({ a: 2.3 })
  console.log(`found ${results}`)
  Deno.exit(1)
}

main()

connecting
connected
found 1

[mdmusaibali]

This issue still remains on deno 1.31.3. mongoose.connect connects successfully to mongodb localhost string but when given mongodb+srv string, connection fails with:

Cannot connect to DB MongoAPIError: Server record does not share hostname with parent URI
 at resolveSRVRecord (file:///home/mdmusaibali/.cache/deno/npm/registry.npmjs.org/mongodb/5.1.0/lib/connection_string.js:60:19)
    at async MongoClient.connect (file:///home/mdmusaibali/.cache/deno/npm/registry.npmjs.org/mongodb/5.1.0/lib/mongo_client.js:117:27)
    at async _createMongoClient (file:///home/mdmusaibali/.cache/deno/npm/registry.npmjs.org/mongoose/7.0.2/lib/connection.js:859:3)
    at async NativeConnection.openUri (file:///home/mdmusaibali/.cache/deno/npm/registry.npmjs.org/mongoose/7.0.2/lib/connection.js:728:5)
    at async file:///home/mdmusaibali/Documents/GitHub/pda-paper-validation-deno-ts/db/mongo.ts:6:5

Connection code:

import mongoose from "npm:mongoose@7.0.2";
try {
  const MONGO_URL = Deno.env.get("MONGO_URL");
  if (MONGO_URL) {
    await mongoose.connect(
      "mongodb+srv://<username>:<password>@cluster0.byaerrd.mongodb.net/<db-name>?retryWrites=true&w=majority"
    );
    console.log("Connected to db");
  }
} catch (error) {
  if (error instanceof Error) {
    console.log("Cannot connect to DB", error);
  }
}

[avalero]

Damn! I hope this is fixed soon. It is very annoying not being able to work with mongo and Deno, and MongoDB Deno native library is abandoned and I think is does not support MongoDB v6

[jyemin]

@avalero can you clarify whether you are not able to using MongoDB at all with Deno, or if the issue is only with support for "mongodb+srv" connection string (see @alexbevi's comment just above).

[avalero]

With the "mongodb+srv" connection string

[jyemin]

To get a non-SRV connection string, click the Connect button in the Atlas UI, choose the Node.js driver, and then select 2.2.12 or later. The connection string supplied for this version will work with all later versions of the Node.js driver and should also work with Deno.

[hazelnutcloud]

I think I have figured out the source of this problem. When connecting with the mongodb+srv protocol, the node.js mongo driver compares the resolved SRV records against the parent domain.

To do that, it calls resolveSrv() function imported from node's dns module. Calling this API from Deno results in trailing dots in the name field of the objects in the array returned by the resolveSrv() function meanwhile running it node produces no trailing dots

Here's the code I used to test this:

import dns from "node:dns";

console.log(await dns.promises.resolveSrv("_mongodb._tcp.cluster.1abcd.mongodb.net"))

And here are the outputs when running in Deno:

[
  {
    priority: 0,
    weight: 0,
    port: 27017,
    name: "cluster-shard-00-01.1abcd.mongodb.net."
  },
  {
    priority: 0,
    weight: 0,
    port: 27017,
    name: "cluster-shard-00-02.1abcd.mongodb.net."
  },
  {
    priority: 0,
    weight: 0,
    port: 27017,
    name: "cluster-shard-00-00.1abcd.mongodb.net."
  }
]

in node:

[
  {
    priority: 0,
    weight: 0,
    port: 27017,
    name: "cluster-shard-00-01.1abcd.mongodb.net"
  },
  {
    priority: 0,
    weight: 0,
    port: 27017,
    name: "cluster-shard-00-02.1abcd.mongodb.net"
  },
  {
    priority: 0,
    weight: 0,
    port: 27017,
    name: "cluster-shard-00-00.1abcd.mongodb.net"
  }
]

I edited all the hostnames displayed there to hide some info but that's what it should look like.

@bartlomieju @crowlKats

[hazelnutcloud]

calling Deno.resolveDns("...", "SRV") also results in the same behavior (produces trailing dots)

[alexbevi]

@hazelnutcloud from a MongoDB Driver POV a bug for this was reported previously (see NODE-5042) which we're hoping to get sorted out soon.

It's really helpful to see further confirmation that resolving this bug should improve the Deno experience using MongoDB!

[bartlomieju]

Thanks for investigating @hazelnutcloud, @crowlKats is looking into this issue and it should be fixed in the coming days.

[eikooc]

Just chiming in with an update. The ticket over at MongoDB's Jira is marked as done with fix version v5.3.0.

https://jira.mongodb.org/browse/NODE-5042

[alexbevi]

@eikooc you beat me to it :) The MongoDB Node Driver team addressed this with https://github.com/mongodb/node-mongodb-native/commit/051b8615ac0ebebb8c07d7a661bf1ab4f99cf4b2, which will be included in the next release of the driver.

I'll close this issue out once the release is made :)

[alexbevi]

FYI https://github.com/mongodb/node-mongodb-native/releases/tag/v5.3.0 has been released, which includes the fixes to SRV resolution that were affecting Deno. There may still be an opportunity to address this behavior in Deno directly, but for now the MongoDB driver should work :)

[topperspal]

It now started connecting to MongoDB with npm:mongodb@5.6.0 from Atlas uri. I can use CRUD operations but it throws error after a few minutes

error: Uncaught Error: read ECONNRESET
    at __node_internal_captureLargerStackTrace (ext:deno_node/internal/errors.ts:89:11)
    at __node_internal_errnoException (ext:deno_node/internal/errors.ts:137:12)
    at TCP.onStreamRead [as onread] (ext:deno_node/internal/stream_base_commons.ts:205:24)
    at TCP.#read (ext:deno_node/internal_binding/stream_wrap.ts:223:18)
    at eventLoopTick (ext:core/01_core.js:183:11)

[eikooc]

@topperspal I experience the same thing

[TillaTheHun0]

I am experiencing the same issue as @topperspal on npm:mongodb@5.6.0 and Deno 1.35.0. At first, operations performed using the driver succeed, but then after a few minutes, I get that same ECONNRESET error which crashes the process.

Perhaps worth noting that 5.6.0 introduced support for Node 20, so maybe some regression with node compat?

[eikooc]

@TillaTheHun0 if you can create a minimal reproduction then there's this issue where you can post it https://github.com/denoland/deno/issues/19078

I haven't been able to create a succesful minimal production showing the error.

[TillaTheHun0]

@eikooc I posted a repo with steps to reproduce. I was only able to replicate with an Atlas Serverless Cluster, which seems correlated, but can't say for sure without digging deeper.

https://github.com/TillaTheHun0/deno-mongo-atlas-repro

[eikooc]

I've noticed that this happens every time the MongoDB cluster scales up or down so the connection is cut.

[eikooc]

I believe this has been fixed in v1.37 https://github.com/denoland/deno/pull/20314. Right now it is possible to update by running deno upgrade --canary

[bartlomieju]

Thanks for checking @eikooc! Let's close the issue then.

[fro-profesional]

I jus tried on local an deploy and seems to be working with MongoDB Atlas serverless deno v1.37

import { MongoClient } from "npm:mongodb"
import { ulid } from "https://deno.land/std@0.202.0/ulid/mod.ts";

const client = new MongoClient("<url>")

client.connect();

Deno.serve(async () => {

  const data = await client.db("deno").collection("deno").insertOne({
    name: ulid()
  })

  return new Response(JSON.stringify({
    data
  }), {
    headers: { "Content-Type": "application/json" },
  })
})

[ryvwel]

It now started connecting to MongoDB with npm:mongodb@5.6.0 from Atlas uri. I can use CRUD operations but it throws error after a few minutes

error: Uncaught Error: read ECONNRESET
    at __node_internal_captureLargerStackTrace (ext:deno_node/internal/errors.ts:89:11)
    at __node_internal_errnoException (ext:deno_node/internal/errors.ts:137:12)
    at TCP.onStreamRead [as onread] (ext:deno_node/internal/stream_base_commons.ts:205:24)
    at TCP.#read (ext:deno_node/internal_binding/stream_wrap.ts:223:18)
    at eventLoopTick (ext:core/01_core.js:183:11)

Does anyone experience this error yet? It happens so random i can't reproduce it locally, but my serverless service sometimes crashes because of this

UPD: according to my atlas metrics, it happens on server restarts, so nevermind

[alexbevi]

@ryvwel that's just a socket error, so "why" the connection was closed would need investigation (it's likely not a Deno, or even MongoDB issue). Note that MongoDB's drivers support automatic retryability of reads and writes so it's possible the associated operation may not have even failed (though you may see a logged error).

This is likely a transient network error, so handling the uncaught exception and allowing the driver's connection pool to heal itself should allow you to continue normal operations.

[jantoney]

@ryvwel @topperspal I think the issue around error: Uncaught Error: read ECONNRESET might be related to #21951 If correct, it is something around a CLOSE and ERROR event being out of order in Deno.

Further links to others in that issue