private void RegisterResolverClassesMethods()
{
foreach (var module in _server.Modules)
{
foreach (var resClass in module.ResolverClasses)
{
var resClassInfo = new ResolverClassInfo()
{
Module = module, Type = resClass
};
_model.ResolverClasses.Add(resClassInfo);
var methods = resClass.GetPublicMethods();
foreach (var m in methods)
{
var resAttr = m.GetAttribute <ResolvesFieldAttribute>();
var resInfo = new ResolverMethodInfo()
{
Method = m, Module = module, ResolverClass = resClassInfo, ReturnsTask = m.MethodReturnsTask(),
ReturnType = m.GetReturnDataType(), ResolvesAttribute = resAttr
};
if (resInfo.ReturnsTask)
{
resInfo.TaskResultReader = ExpressionHelper.CompileTaskResultReader(m.ReturnType);
}
_allResolverMethods.Add(resInfo);
}
}
}
}
private bool VerifyFieldResolverMethod(FieldDef field, ResolverMethodInfo resolverMethod)
{
if (!VerifyResolverMethodReturnTypeCompatible(field, resolverMethod.Method))
{
return(false);
}
if (!ValidateResolverMethodArguments(field, resolverMethod))
{
return(false);
}
return(!_model.HasErrors);
}
private bool ValidateResolverMethodArguments(FieldDef fieldDef, ResolverMethodInfo resolverMethod)
{
var resMethod = resolverMethod.Method;
// Check first parameter - must be IFieldContext
var prms = resMethod.GetParameters();
if (prms.Length == 0 || prms[0].ParameterType != typeof(IFieldContext))
{
AddError($"Resolver method {resMethod.GetFullRef()}: the first parameter must be of type '{nameof(IFieldContext)}'.");
return(false);
}
// compare list of field parameters with list of resolver method parameters;
// resolver method has extra FieldContext and Parent parameters
var argCountDiff = 1;
if (!fieldDef.Flags.IsSet(FieldFlags.Static))
{
argCountDiff = 2;
}
var expectedPrmCount = fieldDef.Args.Count + argCountDiff;
if (expectedPrmCount != prms.Length)
{
AddError($"Resolver method {resMethod.GetFullRef()}: parameter count mismatch with field arguments, expected {expectedPrmCount}, " +
"with added IFieldContext and possibly Parent object parameter. ");
return(false);
}
// parameter names/types must be identical
for (int i = argCountDiff; i < prms.Length; i++)
{
var prm = prms[i];
var arg = fieldDef.Args[i - argCountDiff];
if (prm.Name != arg.Name || prm.ParameterType != arg.ParamType)
{
AddError($"Resolver method {resMethod.GetFullRef()}: parameter name/type mismatch with field argument; parameter: {prm.Name}.");
return(false);
}
}
return(true);
}
