Hi, i am unable to use the find documentation. Please help.

[shwe2608]

I tried to create the sample kittens db. I am unable to use the find function as documented.

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/fruitsDB', {useNewUrlParser: true, useUnifiedTopology: true});

const kittySchema = new mongoose.Schema({
  name: String
});

const Kitten = mongoose.model('Kitten', kittySchema);

const silence = new Kitten({ name: 'Silence' });
const fluffy = new Kitten({ name: 'fluffy' });

// silence.save()
// fluffy.save()

Kitten.find(function (err, kittens) {
  if (err) return console.error(err);
  console.log(kittens);
})

Getting the following error message in console :

node kittens.js
TypeError: cursor.toArray is not a function
at model.Query. (/Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/mongoose/lib/query.js:2151:19)
at model.Query._wrappedThunk [as _find] (/Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/mongoose/lib/helpers/query/wrapThunk.js:27:8)
at /Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/kareem/index.js:370:33
at processTicksAndRejections (internal/process/task_queues.js:77:11)
(node:30949) UnhandledPromiseRejectionWarning: MongoInvalidArgumentError: Method "collection.find()" accepts at most two arguments
at Collection.find (/Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/mongodb/lib/collection.js:238:19)
at NativeCollection. [as find] (/Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/mongoose/lib/drivers/node-mongodb-native/collection.js:191:33)
at NativeCollection.Collection.doQueue (/Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/mongoose/lib/collection.js:135:23)
at /Users/shwetank/Desktop/Web Development/fruitsDBProject/node_modules/mongoose/lib/collection.js:82:24
at processTicksAndRejections (internal/process/task_queues.js:77:11)
(Use node --trace-warnings ... to show where the warning was created)
(node:30949) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag --unhandled-rejections=strict (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:30949) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Please look into it.

[vkarpov15]

What version of Mongoose are you using? The provided script works as expected in v5.13.7 and v6.0.0, but based on the stack trace you aren't using either of those versions.

[VinDotRun]

I have the same problem. toArray is never used in my code and still get the error TypeError: cursor.toArray is not a function.

I was using Mongoose 5.13.7 with no problems. I upgraded to 6.0.0 and this just happened. Also happens with 6.0.1.

Stack:

[...]\node_modules\mongoose\lib\query.js:2152
    return cursor.toArray(cb);
                  ^

TypeError: cursor.toArray is not a function
    at model.Query.<anonymous> [...]\node_modules\mongoose\lib\query.js:2152:19)
    at model.Query._wrappedThunk [as _find] ( [...]\node_modules\mongoose\lib\helpers\query\wrapThunk.js:27:8)
    at  [...]\node_modules\kareem\index.js:370:33
    at processTicksAndRejections (node:internal/process/task_queues:78:11)

[vkarpov15]

This issue only happens when you call find() before mongoose.connect() succeeds. Fix will be in 6.0.2.

To work around this issue, use await mongoose.connect() to wait for Mongoose to connect before calling find(). Below is the updated find() documentation code that avoids this bug.

const mongoose = require('mongoose');

main().catch(err => console.log(err));

async function main() {
  await mongoose.connect('mongodb://localhost:27017/fruitsDB');

  const kittySchema = new mongoose.Schema({
    name: String
  });

  const Kitten = mongoose.model('Kitten', kittySchema);

  const silence = new Kitten({ name: 'Silence' });
  const fluffy = new Kitten({ name: 'fluffy' });

  const kittens = await Kitten.find();
  console.log(kittens);
}

[lorand-horvath]

@vkarpov15 So from now on do we always have to await mongoose.connect() before calling find()?
Or is this only a temporary workaround until 6.0.2 is released?

[vkarpov15]

@lorand-horvath this is only a temporary workaround until we ship 6.0.2. Sorry for the inconvenience!

[lorand-horvath]

@lorand-horvath this is only a temporary workaround until we ship 6.0.2. Sorry for the inconvenience!

@vkarpov15 I have just tested this and it still errors out even in 6.0.2
I have used this code

mongoose.connect(DB);
(async () => {
    const users = await User.find();
    console.log(users.length);
})().catch(err => console.log(err));

and the error is now different:
(node:5200) UnhandledPromiseRejectionWarning: MongoInvalidArgumentError: Method "collection.find()" accepts at most two arguments ...

If I await mongoose.connect() before User.find(), it works without problems:

(async () => {
    await mongoose.connect(DB);
    const users = await User.find();
    console.log(users.length);
})().catch(err => console.log(err));

Can you please verify? I think something is not working properly in the code which was supposed to fix the issue in 6.0.2: 86f53ad

I've also opened a PR to remove the await before mongoose.connect() in the quickstart #10625 but should be processed only after the actual bug is fixed. Thanks!

[IslandRhythms]

All 3 run without issue

const mongoose = require('mongoose');

const testSchema = new mongoose.Schema({
    name: String
});

const Test = mongoose.model('Test', testSchema);

async function test() {
    await mongoose.connect('mongodb://localhost:27017/test', {
        useNewUrlParser: true,
        useUnifiedTopology: true,
      });
    
      await mongoose.connection.dropDatabase();

      await Test.create({name: 'Test'});

      await Test.find();
      console.log('Done');
}


test();

const mongoose = require('mongoose');

const testSchema = new mongoose.Schema({
    name: String
});

const Test = mongoose.model('Test', testSchema);
mongoose.connect('mongodb://localhost:27017/test', {
        useNewUrlParser: true,
        useUnifiedTopology: true,
      });
    

async function test() {
    
      await mongoose.connection.dropDatabase();

      await Test.create({name: 'Test'});

      await Test.find();
      console.log('Done');
}


test();

const mongoose = require('mongoose');

const testSchema = new mongoose.Schema({
    name: String
});

const Test = mongoose.model('Test', testSchema);
mongoose.connect('mongodb://localhost:27017/test', {
        useNewUrlParser: true,
        useUnifiedTopology: true,
      }).then((res) => console.log('THis statement has executed'));
    

async function test() {
    
      await mongoose.connection.dropDatabase();

      await Test.create({name: 'Test'});

      await Test.find();
      console.log('Done');
}


test();

[vkarpov15]

Below script repros the issue. We'll work on a fix tomorrow 👍

const mongoose = require('mongoose');

const testSchema = new mongoose.Schema({
    name: String
});

const Test = mongoose.model('Test', testSchema);
mongoose.connect('mongodb://localhost:27017/test');
    

async function test() {
      await Test.find();
      console.log('Done');
}


test();

[lorand-horvath]

Below script repros the issue. We'll work on a fix tomorrow +1

@vkarpov15 I already reported it above in #10610 (comment) , including the repro script, see it again below - I guess it wasn't clear enough?
Only difference was that I used an IIFE instead of the named test function as async wrapper. The rest that's not in there is boilerplate anyway, I don't think it adds/changes anything essential :-)

mongoose.connect(DB);
(async () => {
    const users = await User.find();
    console.log(users.length);
})().catch(err => console.log(err));

The point is, this is still a bug and it is reproducible.

[Mgotya]

When this fix will be released? it fixed two day ago but the 6.0.2 release was three days ago so this fix is not a part of 6.0.2

[vkarpov15]

@Mgotya we will release 6.0.3 with 9de60a7 later today.