public DependencyState GetState(DependencyStateContext context)
{
if (!(context is AppConfigValueDependencyStateContext))
{
return(null);
}
// Get the requested AppConfig
var appConfigValueContext = (AppConfigValueDependencyStateContext)context;
var appConfig = AppConfigProvider.GetAppConfigContextless(appConfigValueContext.Name, appConfigValueContext.StoreId, cascadeToDefault: true);
// If the AppConfig doesn't exist or it doesn't match predicate, return a
// state that will be different every time. The required behavior is that any AppConfig
// that doesn't match the predicate should cause the dependecy to fail.
if (appConfig == null || !appConfigValueContext.Predicate(appConfig.ConfigValue))
{
// Generate a random long
var rng = new Random();
var rngBuffer = new byte[8];
rng.NextBytes(rngBuffer);
var failedHash = BitConverter.ToInt64(rngBuffer, 0);
// Return that as the state
return(new DependencyState(
context: context,
state: failedHash));
}
// If the AppConfig exists and matches the predicate, return a state that tracks any changes in the AppConfig.
return(new DependencyState(
context: context,
state: HashProvider.Hash(new object[]
{
appConfigValueContext.Name,
appConfigValueContext.StoreId,
appConfig.StoreId,
appConfig.UpdatedOn.Ticks,
})));
}
public DependencyState GetState(DependencyStateContext context)
{
if (!(context is AppConfigDependencyStateContext))
{
return(null);
}
// Get the requested AppConfig
var appConfigContext = (AppConfigDependencyStateContext)context;
var appConfig = AppConfigProvider.GetAppConfigContextless(appConfigContext.Name, appConfigContext.StoreId, cascadeToDefault: true);
// There are many cases to consider: creation, deletion, and modification; and default
// store fallbacks in all three cases.
// If the requested AppConfig doesn't exist, create a state that doesn't include the value
if (appConfig == null)
{
return(new DependencyState(
context: context,
state: HashProvider.Hash(new object[]
{
appConfigContext.Name,
appConfigContext.StoreId,
})));
}
// Create a state that includes both the requested and actual values.
return(new DependencyState(
context: context,
state: HashProvider.Hash(new object[]
{
appConfigContext.Name, // The name of the AppConfig
appConfigContext.StoreId, // The requested store ID
appConfig.StoreId, // The actual store ID, in case the requested
// store ID used the default store's value
appConfig.UpdatedOn, // The timestamp of the last change
})));
}
