Discussion on: Testing Node.js + Mongoose with an in-memory database

[manuel114]

Hey, I've been struggling to get mongodb-memory-server to work on Circle Ci, any chance you could share your CircleCi config? I keep getting this error when running tests on the CI pipeline:

Error: Status Code is 403 (MongoDB's 404)
This means that the requested version-platform combination dosnt exist

This is my db configuration:

const mongoose = require('mongoose');
const { MongoMemoryServer } = require('mongodb-memory-server');

const mongod = new MongoMemoryServer();

/**
 * Connect to the in-memory database.
 */
module.exports.connect = async () => {
    const uri = await mongod.getUri();

    const mongooseOpts = {
        useNewUrlParser: true,
        autoReconnect: true,
        reconnectTries: Number.MAX_VALUE,
        reconnectInterval: 1000,
    };

    await mongoose.connect(uri, mongooseOpts);
};

[Paula Santamaría]

🤔 looks like MongoMemoryServer is trying to download a binary for the default MongoDB version that is compatible with the OS running on your CircleCI server/container but can't find it.

I've never worked with CircleCI but I'd recommend you to check if the MongoDB version that MongoMemoryServer is trying to download is available for your OS & architecture.
Here's the code where the download URL for the binaries is generated, in case you want to check that out: MongoBinaryDownloadUrl.

Maybe you can set a specific version of MongoDB that exists for your platform, like this:

    mongod = await MongoMemoryServer.create({ binary: { version: '4.2.6' } });
    const uri = await mongod.getConnectionString();

Another way to go would be to activate debug mode so you can get more info on the error. Just set the debug option to "1" in the package.json config section. More info here

[Kowshik Sundararajan]

Thanks for the suggestion, Paula. I found that for my circleci build, specifying a version like 4.2.6 did not work but specifying latest worked.

Hope that helps!