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+---
+layout: post
+title:  "Create a CRUD Web API in minutes with Data API Builder and EF Core Power Tools"
+date:   2024-08-05 18:28:49 +0100
+categories: dotnet sqlserver powertools
+---
+
+[Data API Builder](https://learn.microsoft.com/en-us/azure/data-api-builder/overview) is a .NET container based app, that based on a [json configuration file](https://learn.microsoft.com/azure/data-api-builder/reference-configuration) can expose a CRUD Web API exposing both REST and GrphQL endpoints. 
+
+The app is .NET 8 cross platform, [open source](https://github.com/Azure/data-api-builder) on GitHub and also includes a .NET [command line tool](https://learn.microsoft.com/azure/data-api-builder/reference-command-line-interface) `dab` to create the rather complex configuration file.
+
+But even creating the command line statements to expose an existing database as a Web API can be complex and error prone.
+
+But thanks to the database reverse engineering capabilities of EF Core Power Tools, you can now scaffold these commands in seconds, and try out the API via the `dab start` command on your developer machine.
+
+Given that you already have an existing Azure SQL, SQL Server, Postgres or MySQL database (or SQL Database project), that you want to expose as a CRUD API, a Visual Studio 2022 project for storing the configuration files in source control, and [EF Core Power Tools](https://marketplace.visualstudio.com/items?itemName=ErikEJ.EFCorePowerTools&ssr=false#overview) installed, let's see the three step process to get the API defined and running.
+
+## Generate dab command file
+
+First step is to point to an existing database, and generate a .cmd file with the commands to install and run the `dab` CLI.
+
+From the project context menu, select `EF Core Power Tools`, then `Data API Builder Scaffold (preview)`
+
+![]({{ site.url }}/assets/dab1.png)
+
+Then pick your database connection or add a connection to one of the supported database servers
+
+![]({{ site.url }}/assets/dab2.png)
+
+Pick the database objects and columns that you want to include in your API
+
+![]({{ site.url }}/assets/dab3.png)
+
+Press OK to generate the .cmd file, that will open in the Visual Studio editor.
+
+![]({{ site.url }}/assets/dab4.png)
+
+## Create .env file
+
+In the project, create a file called .env with the following contents - this file is referenced by the `dab`CLI in order connect to the database.
+
+```dos
+dab-connection-string=Data Source=.\SQLEXPRESS;Initial Catalog=Chinook;Integrated Security=True;Encrypt=false
+```
+
+ **Make sure to exclude this file from source control!** 
+
+To do this, add this line to your .gitignore file:
+
+```dos
+.env
+```
+
+## 'Build' and run the API
+
+Right click the project, and select "Open in Termainl" to open Developer PowerShell window and run the cmd file to install the DAB CLI and build the Data API Builder configuration.
+
+```dos
+ .\dab-config.cmd
+```
+You can then validate the generated configuration.
+
+```dos
+dab validate
+```
+
+If validation passes, you can now run the API locally.
+
+```dos
+dab start
+```
+
+Finally, navigate to `http://localhost:5000/swagger` to interact with the API via Swagger UI.
+
+![]({{ site.url }}/assets/dab5.png)
+
+Have a look at the [deployment guide](https://learn.microsoft.com/azure/data-api-builder/deployment/) for advice on how to deploy the Data API container with your configuration.
+
+## Plans for this feature
+
+This EF Core Power Tools feature is currently in preview. One of the goals of the preview is to determine what additional features and options are needed to avoid having to hand-edit the generated dab.config.cmd file, so it can be re-generated if the source schema changes.
+
+So please, try out the preview and submit your feedback and bug reports on [GitHub](https://github.com/ErikEJ/EFCorePowerTools/issues).