public FunctionDefinition Create(FunctionLoadRequest request)
{
FunctionMetadata metadata = request.ToFunctionMetadata();
if (metadata.PathToAssembly == null)
{
throw new InvalidOperationException("The path to the function assembly is null.");
}
if (metadata.EntryPoint == null)
{
throw new InvalidOperationException("The entry point is null.");
}
var entryPointMatch = _entryPointRegex.Match(metadata.EntryPoint);
if (!entryPointMatch.Success)
{
throw new InvalidOperationException("Invalid entry point configuration. The function entry point must be defined in the format <fulltypename>.<methodname>");
}
string typeName = entryPointMatch.Groups["typename"].Value;
string methodName = entryPointMatch.Groups["methodname"].Value;
Assembly assembly = AssemblyLoadContext.Default.LoadFromAssemblyPath(metadata.PathToAssembly);
Type?functionType = assembly.GetType(typeName);
MethodInfo?methodInfo = functionType?.GetMethod(methodName);
if (methodInfo == null)
{
throw new InvalidOperationException($"Method '{methodName}' specified in {nameof(FunctionMetadata.EntryPoint)} was not found. This function cannot be created.");
}
IFunctionInvoker invoker = _functionInvokerFactory.Create(methodInfo);
IEnumerable <FunctionParameter> parameters = methodInfo.GetParameters()
.Where(p => p.Name != null)
.Select(p => new FunctionParameter(p.Name !, p.ParameterType));
return(new DefaultFunctionDefinition(metadata, invoker, parameters));
}
public async Task ExecuteAsync(FunctionContext context)
{
var invoker = _invokerCache.GetOrAdd(context.FunctionId,
_ => _invokerFactory.Create(context.FunctionDefinition));
object?instance = invoker.CreateInstance(context.InstanceServices);
var modelBindingFeature = context.Features.Get <IModelBindingFeature>();
object?[] inputArguments;
if (modelBindingFeature is null)
{
Log.ModelBindingFeatureUnavailable(_logger, context);
inputArguments = new object?[context.FunctionDefinition.Parameters.Length];
}
else
{
inputArguments = modelBindingFeature.BindFunctionInput(context);
}
context.GetBindings().InvocationResult = await invoker.InvokeAsync(instance, inputArguments);
}
