EnvironmentDependentValues.md

Environment Dependent Values

Downloads The code samples used in this user guide have been made available in the Be.Stateless.BizTalk.Factory.Samples GitHub repository.

Having different configuration property values with each target deployment environment is a typical deployment scenario, which is usually achieved through configuration files that vary between environments. The equivalent of the Microsoft BizTalk Server® configuration file is its management database, which is populated primarily when importing XML bindings. As we have seen, the XML bindings to be imported during deployment are generated based on the C# code-first bindings written with the Binding DSL configuration API of BizTalk.Factory.

Instead of having different configuration files we need to produce XML binding files according to their target deployment environments. To support this simple scenario, BizTalk.Factory's Binding DSL provides three static helper classes that interact with ech other:

• A DeploymentContext, that provides a read-only —actually, settable via unit testing helper classes or PowerShell deployment commands— string property, TargetEnvironment, that denotes the environment for which the XML bindings are currently being generated.

• A TargetEnvironment class that provides a predefined list of target environments ordered according to their maturity level —i.e. DEVELOPMENT = "DEV", BUILD = "BLD", INTEGRATION = "INT", ACCEPTANCE = "ACC", PREPRODUCTION = "PRE", and PRODUCTION = "PRD",— and few predicate extension methods helping to determine the current target deployment environment or a minimum one, allowing the developer to write code as follows:

  using Be.Stateless.BizTalk.Install;
  
  // true if DeploymentContext.TargetEnvironment is "PRD"
  if (DeploymentContext.TargetEnvironment.IsProduction()) {
     ...
  }
  
  // true if DeploymentContext.TargetEnvironment is "ACC" or "PRE" or "PRD"
  if (DeploymentContext.TargetEnvironment.IsAcceptanceUpwards()) {
     ...
  }

• EnvironmentDependentValue provides strongly typed extensions methods ensuring that, for a given configuration property, a value, of the correct type, is defined for each target environment; allowing the developer to write code as follows:

  using Be.Stateless.BizTalk.Install;
  
  public static class Settings
  {
     public static DateTime DateProperty => EnvironmentDependentValue
  		.ForDevelopment(new DateTime(2021, 3, 3))
  		.ForAcceptanceUpwards(DateTime.MinValue);
  
  	public static int IntegerProperty => EnvironmentDependentValue
  		.ForAcceptance(1)
  		.ForBuild(2)
  		.ForDevelopment(3)
  		.ForPreProduction(4)
  		.ForProduction(5);
  
  	public static string StringProperty => EnvironmentDependentValue
  		.ForDevelopmentOrBuild("one.1")
  		.ForAcceptance("one.2")
  		.ForPreProductionUpwards("one.3");
  }

  Recall that we have an automated test that validates that the XML bindings can be generated for all the target deployment environments that concern us. This test now fails throwing a couple of NotSupportedExceptions saying that 'DateProperty' does not provide a value for target environment 'BLD' and 'DateProperty' does not provide a value for target environment 'INT', therefore ensuring that the developer does not forget to define them.

Remark The developer is obviously free to define his own custom list of target environments, but then he would have to redefine his own equivalent of the TargetEnvironment and EnvironmentDependentValue classes.