How to Change your Connection String According to the Domain at Runtime in ASP.NET Core

Discover how to dynamically change your database connection string based on the domain in your ASP.NET Core application with this comprehensive guide.
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How to Change your Connection String According to the Domain at Runtime in ASP.NET Core

In web development, applications often need to interact with databases, necessitating the configuration of connection strings. However, there are situations where you might want to change the database connection string dynamically based on the domain. This is common in multi-tenant applications, where different tenants might require different databases.

Understanding the Problem

When building APIs or web applications, having a single connection string can limit your application’s flexibility, especially if you're serving requests from multiple domains. For example, you may have different environments such as development, testing, and production, or even distinct databases for separate clients. Changing the connection string on the fly can help manage these variations more effectively.

The Solution Overview

We will leverage dependency injection along with the IHttpContextAccessor interface to access the HTTP context in the DbContext. This approach involves:

Modifying the constructor and OnConfiguring method in the DbContext.

Step-by-Step Implementation

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Modify Your DbContext

Next, you’ll need to modify your DbContext class. Specifically, you will adjust the constructor to accept the IHttpContextAccessor and set up the OnConfiguring method to change the connection string based on the incoming domain.

Update the Constructor

Here’s how you can adjust the constructor:

[[See Video to Reveal this Text or Code Snippet]]

Change the OnConfiguring Method

Now, implement the logic in the OnConfiguring method to dynamically set the connection string:

[[See Video to Reveal this Text or Code Snippet]]

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following these steps, you can dynamically configure your database connection strings based on the domain at runtime in your ASP.NET Core application. This flexibility allows you to manage multiple databases effectively and adapt to the unique requirements of each client or environment.

Be sure to test this implementation thoroughly in your development environment before deploying to production to avoid any unforeseen issues. Happy coding!