Maintaining App Config For Dev, QA And Prod Regions

Maintaining different app.config files for different regions can be a pain and also prone to errors. Using the Config sections in the config files can be one of the ways to solve the problem.

Recently, I was working with a client who has just started with the adoption of cloud technologies and they have a long roadmap before they reach Kubernetes or a container-based development approach. 

 

There were a few batch jobs that I was supposed to write, that would perform some push/pull from the existing LOBs to Azure. This was to minimize my efforts so that I don't have to maintain different configs for each region like DEV, QA, and PROD. I wrote a custom config section to be able to slice the different app settings based on the region. Here are some details and codes.

Custom Config Section Entry in the App.Config  

<configSections>
    <section name ="serverConfiguration" type ="ServerConfiguration.ServerSettingHandler, ServerConfiguration"/>
  </configSections>

<serverConfiguration>
    <server name ="Dev">
      <settings>
        <add key ="ck" value ="ckDEV"   />
        <add key ="abc" value ="mlDEV"   />
        <add key ="cde" value ="p3DEV"   />
        <add key ="efg" value ="oppDEV"   />
      </settings>
    </server>
    <server name ="QA">
      <settings>
        <add key ="ck" value ="ckQA"   />
        <add key ="abc" value ="mlQA"   />
        <add key ="cde" value ="p3QA"   />
        <add key ="efg" value ="oppQA"   />
      </settings>
    </server>
    <server name ="PRD">
      <settings>
        <add key ="ck" value ="ckPRD"   />
        <add key ="abc" value ="mlPRD"   />
        <add key ="cde" value ="p3PRD"   />
        <add key ="efg" value ="oppPRD"   />
      </settings>
    </server>
  </serverConfiguration>

Fetch the Specific Setting Value 

 var server = ServerConfigManager.GetServerSetting("dev","ck");

 Console.WriteLine(server);

// Prints
// ckDEV

Fetch the All Setting Value

var server = ServerConfigManager.GetServer("Dev");

           foreach (KeyValuePair<string, string> setting in server?.Settings)
           {
               Console.WriteLine($"Key : {setting.Key} Value : {setting.Value}");
           }
// Prints
/*
Key : ck Value : ckDEV
Key : abc Value : mlDEV
Key : cde Value : p3DEV
Key : efg Value : oppDEV
*/

Other Wrappers

If you decide to name the server with the Machine name, then you can also make use of the below method for fetching the details.

// The GetCurrentServer uses the Environment.MachineName to look in the Config sections and Fetches the value.
var server = ServerConfigManager.GetCurrentServer()

Attached code has all the source files.

 

I know this has been available in C# for almost a decade or so, but this blog may be a good read to refresh your knowledge on this old technique.