/// <summary>
/// Load the configuration data from the PubComp CacheConfig ConfigurationSource
/// and return it as an ordered list of relevant ConfigNode types
/// e.g.:
/// "PubComp:CacheConfig:NoCache1:Assembly"->"PubComp.Caching.Core",
/// "PubComp:CacheConfig:NoCache1:Type"->"NoCache",
/// "PubComp:CacheConfig:YesCache2:Assembly"->"PubComp.Caching.Core",
/// "PubComp:CacheConfig:YesCache2:Type"->"JustAnExampleCache",
/// ...
/// </summary>
/// <returns>The list of Cache ConfigNode (and its inheriting classes)</returns>
public IList <ConfigNode> LoadConfig()
{
var loadErrors = new CacheConfigLoadErrorsException();
var assemblies = new Dictionary <string, Assembly>();
var configNodes = new List <ConfigNode>();
var cacheConfigs = pubCompCacheConfigurationSection.GetChildren();
foreach (var cacheConfig in cacheConfigs)
{
if (cacheConfig.GetValue <ConfigAction>("action") == ConfigAction.Remove)
{
configNodes.Add(new RemoveConfig {
Action = ConfigAction.Remove, Name = cacheConfig.Key
});
continue;
}
var typeName = cacheConfig["type"] + "Config";
var assemblyName = cacheConfig["assembly"];
if (!assemblies.TryGetValue(assemblyName, out var assembly))
{
try
{
assembly = Assembly.Load(assemblyName);
}
catch (Exception ex) when(ex is FileLoadException ||
ex is FileNotFoundException ||
ex is BadImageFormatException)
{
LogConfigError(loadErrors, $"Could not load assembly {assemblyName} for type {typeName}", ex);
continue;
}
assemblies.Add(assemblyName, assembly);
}
var configType = assembly.GetType(typeName, false, false);
if (configType == null)
{
configType = assembly.GetType(assemblyName + '.' + typeName, false, false);
}
if (configType == null)
{
LogConfigError(loadErrors, $"Could not load type {typeName} from assembly {assemblyName}");
continue;
}
var configNode = cacheConfig.Get(configType) as ConfigNode;
configNode.Name = cacheConfig["Name"] ?? cacheConfig.Key; // Use explicit name if possible. Key is the fallback name.
configNodes.Add(configNode);
}
if (!loadErrors.IsEmpty())
{
throw loadErrors;
}
return(configNodes);
}
// TODO: Use real log here - and throw a fatal exception instead of swallowing the missing assembly/type
private void LogConfigError(
CacheConfigLoadErrorsException loadErrors, string error, Exception ex = null)
{
System.Diagnostics.Debug.WriteLine(
ex != null
? $"{typeof(MicrosoftExtensionsCacheConfigLoader).FullName}: {error}, Exception: {ex}"
: $"{typeof(MicrosoftExtensionsCacheConfigLoader).FullName}: {error}");
loadErrors.Add(
new CacheConfigLoadErrorsException.CacheConfigLoadError
{
Error = error,
Exception = ex
});
}
