/// <summary>
/// Defined what other bindings can use and return value.
/// </summary>
private IReadOnlyDictionary <string, Type> CreateBindingContract(SignalRTriggerAttribute attribute, ParameterInfo parameter)
{
var contract = new Dictionary <string, Type>(StringComparer.OrdinalIgnoreCase)
{
{ ReturnParameterKey, typeof(object).MakeByRefType() },
};
// Add names in ParameterNames to binding contract, that user can bind to Functions' parameter directly
if (attribute.ParameterNames != null)
{
var parameters = ((MethodInfo)parameter.Member).GetParameters().ToDictionary(p => p.Name, p => p.ParameterType, StringComparer.OrdinalIgnoreCase);
foreach (var parameterName in attribute.ParameterNames)
{
if (parameters.ContainsKey(parameterName))
{
contract.Add(parameterName, parameters[parameterName]);
}
else
{
contract.Add(parameterName, typeof(object));
}
}
}
return(contract);
}
public SignalRTriggerBinding(ParameterInfo parameterInfo, SignalRTriggerAttribute attribute, ISignalRTriggerDispatcher dispatcher)
{
_parameterInfo = parameterInfo ?? throw new ArgumentNullException(nameof(parameterInfo));
_attribute = attribute ?? throw new ArgumentNullException(nameof(attribute));
_dispatcher = dispatcher ?? throw new ArgumentNullException(nameof(dispatcher));
BindingDataContract = CreateBindingContract(_attribute, _parameterInfo);
}
internal SignalRTriggerAttribute GetParameterResolvedAttribute(SignalRTriggerAttribute attribute, ParameterInfo parameterInfo)
{
//TODO: AutoResolve more properties in attribute
var hubName = attribute.HubName;
var category = attribute.Category;
var @event = attribute.Event;
var parameterNames = attribute.ParameterNames ?? Array.Empty <string>();
var connectionStringSetting = attribute.ConnectionStringSetting;
// We have two models for C#, one is function based model which also work in multiple language
// Another one is class based model, which is highly close to SignalR itself but must keep some conventions.
var method = (MethodInfo)parameterInfo.Member;
var declaredType = method.DeclaringType;
string[] parameterNamesFromAttribute;
if (declaredType != null && IsServerlessHub(declaredType))
{
// Class based model
if (!string.IsNullOrEmpty(hubName) ||
!string.IsNullOrEmpty(category) ||
!string.IsNullOrEmpty(@event) ||
parameterNames.Length != 0)
{
throw new ArgumentException($"{nameof(SignalRTriggerAttribute)} must use parameterless constructor in class based model.");
}
parameterNamesFromAttribute = method.GetParameters().Where(IsLegalClassBasedParameter).Select(p => p.Name).ToArray();
hubName = declaredType.Name;
category = GetCategoryFromMethodName(method.Name);
@event = GetEventFromMethodName(method.Name, category);
connectionStringSetting = declaredType.GetCustomAttribute <SignalRConnectionAttribute>()?.Connection ?? attribute.ConnectionStringSetting;
}
else
{
parameterNamesFromAttribute = method.GetParameters().
Where(p => p.GetCustomAttribute <SignalRParameterAttribute>(false) != null).
Select(p => p.Name).ToArray();
if (parameterNamesFromAttribute.Length != 0 && parameterNames.Length != 0)
{
throw new InvalidOperationException(
$"{nameof(SignalRTriggerAttribute)}.{nameof(SignalRTriggerAttribute.ParameterNames)} and {nameof(SignalRParameterAttribute)} can not be set in the same Function.");
}
// If we aren't using the class-based model, make sure we resolve binding expressions for attribute properties here.
hubName = _nameResolver.ResolveWholeString(hubName);
category = _nameResolver.ResolveWholeString(category);
@event = _nameResolver.ResolveWholeString(@event);
}
parameterNames = parameterNamesFromAttribute.Length != 0
? parameterNamesFromAttribute
: parameterNames;
return(new SignalRTriggerAttribute(hubName, category, @event, parameterNames)
{
ConnectionStringSetting = connectionStringSetting
});
}
private static void ValidateSignalRTriggerAttributeBinding(SignalRTriggerAttribute attribute)
{
if (string.IsNullOrWhiteSpace(attribute.ConnectionStringSetting))
{
throw new InvalidOperationException(
$"{nameof(SignalRTriggerAttribute)}.{nameof(SignalRConnectionInfoAttribute.ConnectionStringSetting)} is not allowed to be null or whitespace.");
}
ValidateParameterNames(attribute.ParameterNames);
}
private void ValidateSignalRTriggerAttributeBinding(SignalRTriggerAttribute attribute)
{
if (string.IsNullOrEmpty(attribute.ConnectionStringSetting))
{
throw new InvalidOperationException(string.Format(ErrorMessages.EmptyConnectionStringErrorMessageFormat,
$"{nameof(SignalRTriggerAttribute)}.{nameof(SignalRConnectionInfoAttribute.ConnectionStringSetting)}"));
}
ValidateParameterNames(attribute.ParameterNames);
}
public SignalRTriggerBinding(ParameterInfo parameterInfo, SignalRTriggerAttribute attribute, ISignalRTriggerDispatcher dispatcher, AccessKey[] accessKeys, ServiceHubContext hubContext)
{
_parameterInfo = parameterInfo ?? throw new ArgumentNullException(nameof(parameterInfo));
_attribute = attribute ?? throw new ArgumentNullException(nameof(attribute));
_dispatcher = dispatcher ?? throw new ArgumentNullException(nameof(dispatcher));
_accessKeys = accessKeys ?? throw new ArgumentNullException(nameof(accessKeys));
_hubContext = hubContext;
BindingDataContract = CreateBindingContract(_attribute, _parameterInfo);
}
