Dot Net Core 3.1 - Unable to implement Mongo Atlas healthcheck

Question

I am unable to add the Mongo Atlas health check in dot net core 3.1 using the AspNetCore.HealthChecks.MongoDb nuget package. Added below code into the startup.cs

services.AddHealthChecks().AddMongoDb("MongoDbContext");

endpoints.MapHealthChecks("/api/v1.0/health", new HealthCheckOptions()

When I hit the health URL, it is giving an exception as below

"Status": "Unhealthy",
    "Description": null,
    "Exception": "MongoDB.Driver.MongoCommandException: Command listCollections failed: not authorized on test to execute command

Answer 1

when you have all the configuration stuff done, you should try with adding first the health check definition for MongoDB:

public void ConfigureServices (IServiceCollection services) {
    services.AddControllers ();

    string mongoDBConnection = Configuration.GetValue ("mongoDB:connection");

    services.AddHealthChecks ()
        .AddMongoDb (mongodbConnectionString: mongoDBConnection,
            name: "todo-db-check",
            failureStatus : HealthStatus.Unhealthy,
            tags : new string[] { "todo-api", "mongodb" });
}

Also you need to add connection string info for MongoDB in the app settings file.

"mongoDB:connection": "mongodb://localhost:27017"

Then, add the health check with “/hc” path to the request pipeline.

app.UseEndpoints (endpoints => {
    endpoints.MapControllers ();
    endpoints.MapHealthChecks ("/hc");
});

Now you can run the API and hit the “/hc” endpoint via browser, and it should be in healthy status with its database.

You can also see the documentation for MongoDB (https://docs.mongodb.com/manual/), and and for that specific issue, you should take a look at these pages, to make it clearer.

(https://rmauro.dev/adding-health-checks-to-net-core-application/)

(https://www.gokhan-gokalp.com/en/aspnet-core-series-06-monitor-the-health-of-your-applications-by-implementing-health-checks-and-azure-application-insights/)

Answer 2

Looking at the source code on github

if (!string.IsNullOrEmpty(_specifiedDatabase))
{
    // some users can't list all databases depending on database privileges, with
    // this you can list only collections on specified database.
    // Related with issue #43

    using var cursor = await mongoClient
        .GetDatabase(_specifiedDatabase)
        .ListCollectionNamesAsync(cancellationToken: cancellationToken);
    await cursor.FirstAsync(cancellationToken);
}

the problem seems to be that you don't have enough privileges in Atlas for listing the collections on your database "test"