private MethodDefinition GenerateFactoryMethod(TypeDefinition targetType, int index, ICodeGenerator codeGenerator)
{
if (!targetType.CanMapType())
{
return(null);
}
MethodDefinition targetTypeCtor = targetType.GetMappingConstructor();
if (targetTypeCtor == null)
{
return(null);
}
var factory = new MethodDefinition($"<{targetType.Name}>_generated_{index}",
MethodAttributes.Private | MethodAttributes.HideBySig | MethodAttributes.Static,
ModuleDefinition.ImportReference(targetType));
factory.Parameters.Add(new ParameterDefinition("serviceProvider", ParameterAttributes.None, Import.System.IServiceProvider));
ILProcessor factoryProcessor = factory.Body.GetILProcessor();
MethodReference getServiceMethod = Import.DependencyInjection.ServiceProviderServiceExtensions_GetService;
foreach (ParameterDefinition parameter in targetTypeCtor.Parameters)
{
factoryProcessor.Emit(OpCodes.Ldarg_0);
var genericGetService = new GenericInstanceMethod(getServiceMethod);
genericGetService.GenericArguments.Add(ModuleDefinition.ImportReference(parameter.ParameterType));
factoryProcessor.Emit(OpCodes.Call, genericGetService);
}
factoryProcessor.Emit(OpCodes.Newobj, ModuleDefinition.ImportReference(targetTypeCtor));
factoryProcessor.Emit(OpCodes.Ret);
IMethodGenerator methodGenerator = codeGenerator?.Method(factory);
if (methodGenerator != null)
{
var parameters = string.Join(", ", targetTypeCtor.Parameters.Select(x => $"serviceProvider.GetService<{x.ParameterType.NameCSharp(true)}>()"));
methodGenerator.Append($"return new {targetType.NameCSharp(true)}({parameters});", factoryProcessor.Body.Instructions.First());
methodGenerator.Append(Environment.NewLine);
}
return(factory);
}
private MethodDefinition GenerateAddServicesMethod(Mapping mapping, Settings settings, TypeDefinition containerType, ICodeGenerator codeGenerator)
{
var method = new MethodDefinition("AddServices",
MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.Static,
ModuleDefinition.ImportReference(typeof(void)));
var serviceCollection = new ParameterDefinition("collection", ParameterAttributes.None, Import.DependencyInjection.IServiceCollection);
method.Parameters.Add(serviceCollection);
IMethodGenerator methodGenerator = codeGenerator?.Method(method);
ILProcessor processor = method.Body.GetILProcessor();
VariableDefinition exceptionList = null;
VariableDefinition exception = null;
if (settings.DebugExceptions)
{
var genericType = ModuleDefinition.ImportReference(Import.System.Collections.List.Type.MakeGenericInstanceType(Import.System.Exception));
exceptionList = new VariableDefinition(genericType);
exception = new VariableDefinition(Import.System.Exception);
method.Body.Variables.Add(exceptionList);
method.Body.Variables.Add(exception);
MethodReference listCtor = Import.System.Collections.List.Ctor;
listCtor = listCtor.MakeGenericDeclaringType(Import.System.Exception);
Instruction createListInstruction = Instruction.Create(OpCodes.Newobj, listCtor);
processor.Append(createListInstruction);
processor.Emit(OpCodes.Stloc, exceptionList);
methodGenerator?.Append("List<Exception> list = new List<Exception>();", createListInstruction);
methodGenerator?.Append(Environment.NewLine);
}
MethodReference funcCtor = Import.System.Func2_Ctor;
if (mapping != null)
{
int factoryIndex = 0;
var factoryMethods = new Dictionary <string, MethodDefinition>();
foreach (Registration registration in mapping)
{
try
{
Logger.Debug($"Processing map for {registration.TargetType.FullName}", AutoDI.DebugLogLevel.Verbose);
if (!factoryMethods.TryGetValue(registration.TargetType.FullName,
out MethodDefinition factoryMethod))
{
factoryMethod = GenerateFactoryMethod(registration.TargetType, factoryIndex, codeGenerator);
if (factoryMethod == null)
{
Logger.Debug($"No acceptable constructor for '{registration.TargetType.FullName}', skipping map",
AutoDI.DebugLogLevel.Verbose);
continue;
}
factoryMethods[registration.TargetType.FullName] = factoryMethod;
factoryIndex++;
containerType.Methods.Add(factoryMethod);
}
var tryStart = Instruction.Create(OpCodes.Ldarg_0); //collection parameter
processor.Append(tryStart);
TypeReference importedKey = ModuleDefinition.ImportReference(registration.Key);
Logger.Debug(
$"Mapping {importedKey.FullName} => {registration.TargetType.FullName} ({registration.Lifetime})",
AutoDI.DebugLogLevel.Default);
processor.Emit(OpCodes.Ldtoken, importedKey);
processor.Emit(OpCodes.Call, Import.System.Type.GetTypeFromHandle);
processor.Emit(OpCodes.Ldtoken, ModuleDefinition.ImportReference(registration.TargetType));
processor.Emit(OpCodes.Call, Import.System.Type.GetTypeFromHandle);
processor.Emit(OpCodes.Ldnull);
processor.Emit(OpCodes.Ldftn, factoryMethod);
processor.Emit(OpCodes.Newobj,
ModuleDefinition.ImportReference(
funcCtor.MakeGenericDeclaringType(Import.System.IServiceProvider,
ModuleDefinition.ImportReference(registration.TargetType))));
processor.Emit(OpCodes.Ldc_I4, (int)registration.Lifetime);
processor.Emit(OpCodes.Call, Import.AutoDI.ServiceCollectionMixins.AddAutoDIService);
processor.Emit(OpCodes.Pop);
if (settings.DebugExceptions)
{
Instruction afterCatch = Instruction.Create(OpCodes.Nop);
processor.Emit(OpCodes.Leave_S, afterCatch);
Instruction handlerStart = Instruction.Create(OpCodes.Stloc, exception);
processor.Append(handlerStart);
processor.Emit(OpCodes.Ldloc, exceptionList);
processor.Emit(OpCodes.Ldstr, $"Error adding type '{registration.TargetType.FullName}' with key '{registration.Key.FullName}'");
processor.Emit(OpCodes.Ldloc, exception);
processor.Emit(OpCodes.Newobj, Import.AutoDI.Exceptions.AutoDIException_Ctor);
var listAdd = Import.System.Collections.List.Add;
listAdd = listAdd.MakeGenericDeclaringType(Import.System.Exception);
processor.Emit(OpCodes.Callvirt, listAdd);
Instruction handlerEnd = Instruction.Create(OpCodes.Leave_S, afterCatch);
processor.Append(handlerEnd);
var exceptionHandler =
new ExceptionHandler(ExceptionHandlerType.Catch)
{
CatchType = Import.System.Exception,
TryStart = tryStart,
TryEnd = handlerStart,
HandlerStart = handlerStart,
HandlerEnd = afterCatch,
};
method.Body.ExceptionHandlers.Add(exceptionHandler);
processor.Append(afterCatch);
if (methodGenerator != null)
{
methodGenerator.Append("try" + Environment.NewLine + "{" + Environment.NewLine);
methodGenerator.Append($" {serviceCollection.Name}.{Import.AutoDI.ServiceCollectionMixins.AddAutoDIService.Name}(typeof({importedKey.FullNameCSharp()}), typeof({registration.TargetType.FullNameCSharp()}), new Func<{Import.System.IServiceProvider.NameCSharp()}, {registration.TargetType.FullNameCSharp()}>({factoryMethod.Name}), Lifetime.{registration.Lifetime});", tryStart);
methodGenerator.Append(Environment.NewLine + "}" + Environment.NewLine + "catch(Exception innerException)" + Environment.NewLine + "{" + Environment.NewLine);
methodGenerator.Append($" list.{listAdd.Name}(new {Import.AutoDI.Exceptions.AutoDIException_Ctor.DeclaringType.Name}(\"Error adding type '{registration.TargetType.FullName}' with key '{registration.Key.FullName}'\", innerException));", handlerStart);
methodGenerator.Append(Environment.NewLine + "}" + Environment.NewLine);
}
}
else if (methodGenerator != null)
{
methodGenerator.Append($"{serviceCollection.Name}.{Import.AutoDI.ServiceCollectionMixins.AddAutoDIService.Name}(typeof({importedKey.FullNameCSharp()}), typeof({registration.TargetType.FullNameCSharp()}), new Func<{Import.System.IServiceProvider.NameCSharp()}, {registration.TargetType.FullNameCSharp()}>({factoryMethod.Name}), Lifetime.{registration.Lifetime});", tryStart);
methodGenerator.Append(Environment.NewLine);
}
}
catch (MultipleConstructorException e)
{
Logger.Error($"Failed to create map for {registration}\r\n{e}");
}
catch (Exception e)
{
Logger.Warning($"Failed to create map for {registration}\r\n{e}");
}
}
}
Instruction @return = Instruction.Create(OpCodes.Ret);
if (settings.DebugExceptions)
{
Instruction loadList = Instruction.Create(OpCodes.Ldloc, exceptionList);
processor.Append(loadList);
var listCount = Import.System.Collections.List.Count;
listCount = listCount.MakeGenericDeclaringType(Import.System.Exception);
processor.Emit(OpCodes.Callvirt, listCount);
processor.Emit(OpCodes.Ldc_I4_0);
processor.Emit(OpCodes.Cgt);
processor.Emit(OpCodes.Brfalse_S, @return);
Instruction ldStr = Instruction.Create(OpCodes.Ldstr, $"Error in {AutoDI.Constants.TypeName}.AddServices() generated method");
processor.Append(ldStr);
processor.Emit(OpCodes.Ldloc, exceptionList);
processor.Emit(OpCodes.Newobj, Import.System.AggregateException_Ctor);
processor.Emit(OpCodes.Throw);
if (methodGenerator != null)
{
methodGenerator.Append("if (list.Count > 0)", loadList);
methodGenerator.Append(Environment.NewLine + "{" + Environment.NewLine);
methodGenerator.Append($" throw new {Import.System.AggregateException_Ctor.DeclaringType.Name}(\"Error in {AutoDI.Constants.TypeName}.{method.Name}() generated method\", list);", ldStr);
methodGenerator.Append(Environment.NewLine + "}" + Environment.NewLine);
}
}
processor.Append(@return);
method.Body.OptimizeMacros();
return(method);
}
private void ProcessMethod(TypeDefinition type, MethodDefinition method, ICodeGenerator generator)
{
List <ParameterDefinition> dependencyParameters = method.Parameters.Where(
p => p.CustomAttributes.Any(a => a.AttributeType.IsType(Import.AutoDI.DependencyAttributeType))).ToList();
List <PropertyDefinition> dependencyProperties = method.IsConstructor ?
type.Properties.Where(p => p.CustomAttributes.Any(a => a.AttributeType.IsType(Import.AutoDI.DependencyAttributeType))).ToList() :
new List <PropertyDefinition>();
if (dependencyParameters.Any() || dependencyProperties.Any())
{
Logger.Debug($"Processing method '{method.Name}' for '{method.DeclaringType.FullName}'", DebugLogLevel.Verbose);
var injector = new Injector(method);
IMethodGenerator methodGenerator = generator?.Method(method);
foreach (ParameterDefinition parameter in dependencyParameters)
{
if (!parameter.IsOptional)
{
Logger.Info(
$"Constructor parameter {parameter.ParameterType.Name} {parameter.Name} is marked with {Import.AutoDI.DependencyAttributeType.FullName} but is not an optional parameter. In {type.FullName}.");
}
if (parameter.Constant != null)
{
Logger.Warning(
$"Constructor parameter {parameter.ParameterType.Name} {parameter.Name} in {type.FullName} does not have a null default value. AutoDI will only resolve dependencies that are null");
}
var initInstruction = Instruction.Create(OpCodes.Ldarg, parameter);
var storeInstruction = Instruction.Create(OpCodes.Starg, parameter);
ResolveDependency(parameter.ParameterType, parameter,
new[] { initInstruction },
null,
storeInstruction,
parameter.Name);
}
foreach (PropertyDefinition property in dependencyProperties)
{
FieldDefinition backingField = null;
//Store the return from the resolve method in the method parameter
if (property.SetMethod == null)
{
//NB: Constant string, compiler detail... yuck yuck and double duck
backingField = property.DeclaringType.Fields.FirstOrDefault(f => f.Name == $"<{property.Name}>k__BackingField");
if (backingField == null)
{
Logger.Warning(
$"{property.FullName} is marked with {Import.AutoDI.DependencyAttributeType.FullName} but cannot be set. Dependency properties must either be auto properties or have a setter");
continue;
}
}
//injector.Insert(OpCodes.Call, property.GetMethod);
ResolveDependency(property.PropertyType, property,
new[]
{
Instruction.Create(OpCodes.Ldarg_0),
Instruction.Create(OpCodes.Call, property.GetMethod),
},
Instruction.Create(OpCodes.Ldarg_0),
property.SetMethod != null
? Instruction.Create(OpCodes.Call, property.SetMethod)
: Instruction.Create(OpCodes.Stfld, backingField),
property.Name);
}
methodGenerator?.Append("//We now return you to your regularly scheduled method");
method.Body.OptimizeMacros();
void ResolveDependency(TypeReference dependencyType, ICustomAttributeProvider source,
Instruction[] loadSource,
Instruction resolveAssignmentTarget,
Instruction setResult,
string dependencyName)
{
//Push dependency parameter onto the stack
if (methodGenerator != null)
{
methodGenerator.Append($"if ({dependencyName} == null)", loadSource.First());
methodGenerator.Append(Environment.NewLine + "{" + Environment.NewLine);
}
injector.Insert(loadSource);
var afterParam = Instruction.Create(OpCodes.Nop);
//Push null onto the stack
injector.Insert(OpCodes.Ldnull);
//Push 1 if the values are equal, 0 if they are not equal
injector.Insert(OpCodes.Ceq);
//Branch if the value is false (0), the dependency was set by the caller we wont replace it
injector.Insert(OpCodes.Brfalse_S, afterParam);
//Push the dependency resolver onto the stack
if (resolveAssignmentTarget != null)
{
injector.Insert(resolveAssignmentTarget);
}
//Create parameters array
var dependencyAttribute = source.CustomAttributes.First(x => x.AttributeType.IsType(Import.AutoDI.DependencyAttributeType));
var values =
(dependencyAttribute.ConstructorArguments?.FirstOrDefault().Value as CustomAttributeArgument[])
?.Select(x => x.Value)
.OfType <CustomAttributeArgument>()
.ToArray();
//Create array of appropriate length
Instruction loadArraySize = injector.Insert(OpCodes.Ldc_I4, values?.Length ?? 0);
if (methodGenerator != null)
{
methodGenerator.Append($" {dependencyName} = GlobalDI.GetService<{dependencyType.FullNameCSharp()}>();", resolveAssignmentTarget ?? loadArraySize);
methodGenerator.Append(Environment.NewLine);
}
injector.Insert(OpCodes.Newarr, ModuleDefinition.ImportReference(typeof(object)));
if (values?.Length > 0)
{
for (int i = 0; i < values.Length; ++i)
{
injector.Insert(OpCodes.Dup);
//Push the array index to insert
injector.Insert(OpCodes.Ldc_I4, i);
//Insert constant value with any boxing/conversion needed
InsertObjectConstant(injector, values[i].Value, values[i].Type.Resolve());
//Push the object into the array at index
injector.Insert(OpCodes.Stelem_Ref);
}
}
//Call the resolve method
var getServiceMethod = new GenericInstanceMethod(Import.AutoDI.GlobalDI.GetService)
{
GenericArguments = { ModuleDefinition.ImportReference(dependencyType) }
};
injector.Insert(OpCodes.Call, getServiceMethod);
//Set the return from the resolve method into the parameter
injector.Insert(setResult);
injector.Insert(afterParam);
if (methodGenerator != null)
{
methodGenerator.Append("}", afterParam);
methodGenerator.Append(Environment.NewLine);
}
}
}
}