Managing Connection Strings and API Keys in Code

Storing connection strings or API keys as parameters or variables in Power Query (M Language) within Power BI

Introduction

Storing connection strings or API keys as parameters or variables in Power Query (M Language) within Power BI is a good practice for managing configuration values across multiple reports or dataflows. Here's a step-by-step guide on how to do this.

Open Power Query Editor

In Power BI Desktop, click on "Edit Queries" on the "Home" tab to open the Power Query Editor.

Create a New Parameter

In the Power Query Editor, go to the "Home" tab.

Click on "Manage Parameters."

Define a New Parameter

In the "Manage Parameters" dialog, click on "New Parameter."

Configure Parameter Settings

In the "Create Parameter" dialog, provide the following information:

• Name: Give your parameter a descriptive name (e.g., "ConnectionString").
• Description (optional): Add a brief description to help users understand the parameter's purpose.
• Type: Choose the appropriate data type for your parameter (e.g., Text for a connection string).
• Current Value: Set the initial value for your parameter. This can be a placeholder or a default value.

Usage in Queries

Once your parameter is created, you can reference it in your Power Query queries.

For example, if you have a connection string in your query, replace the connection string with the parameter name.

To do this, select the part of the query where the connection string is used, and then replace it with `ParameterName`.

Apply Changes

After making changes to your queries, click "Close & Apply" in the Power Query Editor to apply the changes to your Power BI report.

Configure Parameter Refresh Options

When you publish your report to the Power BI Service, you can configure how parameters should be managed during refresh.

You can choose to prompt users for parameter values, use default values, or specify parameter values for different environments.

Testing and Deployment

Test your report to ensure that the parameterization of the connection string works as expected.

When deploying to different environments (e.g., development, production), configure the parameter values accordingly.

Power Automate (Optional): If you need to automate the parameterization process further, you can integrate Power Automate (formerly Microsoft Flow) to set parameter values based on specific triggers or conditions.

Summary

By following these steps, you can create and use parameters in Power Query to manage configuration values like connection strings or API keys centrally. This approach makes it easier to maintain and update these values across multiple reports or dataflows and allows for better separation of configuration from your report logic.