# Connecting to MongoDB Atlas with coded automations

> This tutorial shows how to connect to a MongoDB Atlas database from your UiPath coded automations. MongoDB Atlas is a fully-managed cloud database service that provides a reliable and scalable database solution without the need for local installations.

This tutorial shows how to connect to a MongoDB Atlas database from your UiPath coded automations. MongoDB Atlas is a fully-managed cloud database service that provides a reliable and scalable database solution without the need for local installations.

## Context

Here are the ways to implement the MongoDB connection code:

* Copy and paste the code into a `CS` file of your target project.
* Use a custom activity package and the sample `NUPKG` file

When opting to use the sample `NUPKG` file, you have the capability to add the two-factor authentication as an activity within your `XAML` files.

:::tip
Regardless of whether you choose to integrate the MongoDB connection code in your CS files (for coded automations) or XAML files (for low-code automations), remember that you can invoke a coded automation into a low-code one and vice versa. For more information about hybrid automations, visit [Creating hybrid automations - Combining Coded and Low-code Workflows](https://docs.uipath.com/studio/standalone/latest/user-guide/creating-hybrid-automations).
:::

## Prerequisites

1. Ensure you have UiPath Studio (version 2024.10 or later - recommended).
2. Ensure you have a MongoDB Atlas account.
3. Install the `MongoDB.Driver` NuGet package in your project.
   1. Open your UiPath project in Studio.
   2. In the **Design** ribbon, go to **Manage Packages**.
   3. Select **All Packages** or the **.NET** tab.
   4. Search for `MongoDB.Driver`.
   5. Select `MongoDB.Driver`, and then select **Install**.
   6. Accept the license agreement and dependencies.

## Option 1: Copy and paste the code in `CS` files

To use the MongoDB Atlas connection in your coded automation, you can copy and paste the following sample code in a `CS` file from your target project. Make sure the namespace of the file matches with the one of your project name.

:::note
The sample code connects to MongoDB Atlas using the connection string format specific to cloud deployments. Make sure to replace the placeholder credentials with your actual MongoDB Atlas credentials.
:::

```
using System;
using System.Collections.Generic;
using System.Data;
using UiPath.CodedWorkflows;
using UiPath.Core;
using UiPath.Core.Activities.Storage;
using MongoDB.Driver;

namespace MongoDBCodedWorkflowsSample
{
    public class TestConnection : CodedWorkflow
    {
        [Workflow]
        public string Execute(string username, string password, string cluster)
        {
            List<string> databaseNames = new List<string>();
        try
            {
                // Create MongoDB Atlas connection string
                string connectionString = $"mongodb+srv://{username}:{password}@{cluster}/?retryWrites=true&w=majority";
                Console.WriteLine("Connecting to MongoDB Atlas...");
                // Initialize MongoDB client
                var client = new MongoClient(connectionString);
                // List all databases to verify connection
                Console.WriteLine("\nAvailable databases:");
                databaseNames = client.ListDatabaseNames().ToList();
                foreach (var dbName in databaseNames)
                {
                    Console.WriteLine($"- {dbName}");
                }
                Console.WriteLine("\nConnection successful!");
            }
            catch (MongoAuthenticationException authEx)
            {
                Console.WriteLine($"Authentication error: {authEx.Message}");
                Console.WriteLine("Please verify your username and password.");
                throw;
            }
            catch (MongoConnectionException connEx)
            {
                Console.WriteLine($"Connection error: {connEx.Message}");
                Console.WriteLine("Please check your network access settings in MongoDB Atlas.");
                throw;
            }
            catch (Exception ex)
            {
                Console.WriteLine($"MongoDB connection error: {ex.Message}");
                throw;
            }
            return databaseNames;
        }
    }
}
```

### Connection Parameters
* **username**: The database user you created in MongoDB Atlas
* **password**: The password for your database user
* **cluster**: Your cluster hostname from the connection string (e.g., `cluster0.abc123.mongodb.net`)

The sample returns a list of all databases for that specific set of credentials.

**Connection String Format** - MongoDB Atlas uses the `mongodb+srv://` protocol, which:
* Automatically discovers all nodes in your cluster
* Provides automatic failover support
* Includes retry logic for write operations (`retryWrites=true`)
* Sets the write concern to majority (`w=majority`)

### Error Handling
* **MongoAuthenticationException**: Occurs when credentials are incorrect
* **MongoConnectionException**: Occurs when network access is blocked or cluster is unavailable
* **General exceptions**: Catches any other MongoDB-related errors

## Option 2: Use a custom activity package and the sample `NUPKG` file

Using a sample `NUPKG` file enables you to include the two-factor code in your automations.

1. [Download the `NUPKG` file](https://github.com/UiPath/codedautomations-samples/tree/main/MongoDBSample).
2. Upload the downloaded `NUPKG` file to your **Orchestrator Host** or **Tenant** feed, which are accessible through your Studio instance. For more information on uploading the `NUPKG` file as a custom library to Orchestrator, refer to [Manually uploading a library to Orchestrator](https://docs.uipath.com/orchestrator/automation-cloud/latest/user-guide/managing-libraries#manually-uploading-a-library-to-orchestrator).
3. Open your Studio project and open the **Manage Packages** menu.
4. Search for the `MongoDB.Coded.Workflows.Sample` `NUPKG` file you previously saved to your **Orchestrator Host** or **Orchestrator Tenant** feed, and install it.

Figure 1. Custom library in the Manage Packages menu

   ![custom library in the Manage Packages menu](https://dev-assets.cms.uipath.com/assets/images/studio/studio-custom-library-in-the-manage-packages-menu-624592-db436420.webp)
   
5. After you install the file, navigate to the **Activities** panel and locate `MongoDB.Coded.Workflows.Sample`. Drag and drop the **GetDatabases** activity into your `XAML` files to test your MongoDB connection and fetch a list of the available databases.

Figure 2. GetDatabases activity in the Activities panel

   ![GetDatabases activity in the Activities panel](https://dev-assets.cms.uipath.com/assets/images/studio/studio-getdatabases-activity-in-the-activities-panel-624598-cb10662c.webp)