public QueryInfo(Type queryType, ICqrsOptions options)
{
QueryType = queryType;
IsAsync = queryType.IsAssignableToGenericType(typeof(IAsyncQuery <>));
ResultType = DetermineResultTypes(queryType, IsAsync).Single();
HttpMethods = queryType
.GetCustomAttributes(true)
.OfType <HttpMethodAttribute>()
.SelectMany(x => x.HttpMethods)
.Distinct()
.ToArray();
if (!HttpMethods.Any())
{
HttpMethods = options.DefaultQueryHttpMethods;
}
if (IsAsync)
{
QueryHandlerType = typeof(IAsyncQueryHandler <,>).MakeGenericType(QueryType, ResultType);
}
else
{
QueryHandlerType = typeof(IQueryHandler <,>).MakeGenericType(QueryType, ResultType);
}
}
private async Task HandleCommand(HttpContext context, ICqrsOptions options)
{
var path = options.GetCommandPath(context.Request.Path.Value);
if (!_commandTypes.Value.ContainsKey(path))
{
throw new CommandNotFoundException($"Command '{path}' not found");
}
dynamic result = null;
var info = _commandTypes.Value[path];
var exposeAttribute = info.CommandType.GetCustomAttribute <ExposeAttribute>();
var formatter = _registry.GetFormatter(exposeAttribute.Formatter);
var deserializeMethod = _deserializeMethods.GetOrAdd(info.CommandType, (t) =>
{
var mi = CreateDeserializeLambdaMethodInfo.MakeGenericMethod(t);
return(mi.Invoke(null, null));
});
dynamic command = await deserializeMethod(formatter, context.Request);
dynamic handler = _container.GetInstance(info.CommandHandlerType);
context.Items[ContextKey] = new CqrsContext(context.Request.Path.Value, path, CqrsType.Command, info.CommandHandlerType);
if (info.IsGeneric)
{
if (info.IsAsync)
{
result = await handler.HandleAsync(command, context.RequestAborted);
}
else
{
result = handler.Handle(command);
}
}
else
{
if (info.IsAsync)
{
await handler.HandleAsync(command, context.RequestAborted);
}
else
{
handler.Handle(command);
}
}
CloseSession();
var json = result is string?result : await formatter.SerializeAsync(result, context.Request);
context.Response.ContentType = formatter.ContentType;
context.Response.StatusCode = (int)HttpStatusCode.OK;
await HttpResponseWritingExtensions.WriteAsync(context.Response, json, context.RequestAborted);
}
private async Task HandleQuery(HttpContext context, ICqrsOptions options)
{
var path = context.Request.Path.Value;
var method = context.Request.Method;
if (!_queryTypes.Value.ContainsKey($"{method} {path}"))
{
throw new QueryNotFoundException($"Query '{method} {path}' not found");
}
var info = _queryTypes.Value[$"{method} {path}"];
var exposeAttribute = info.QueryType.GetCustomAttribute <ExposeAttribute>();
var formatter = _registry.GetFormatter(exposeAttribute.Formatter);
var deserializeMethod = _deserializeMethods.GetOrAdd(info.QueryType, (t) =>
{
var mi = CreateDeserializeLambdaMethodInfo.MakeGenericMethod(t);
return(mi.Invoke(null, null));
});
var query = await deserializeMethod(formatter, context.Request);
dynamic handler = options.GetInstance(info.QueryHandlerType);
context.Items[IOwinContextExtensions.ContextKey] = new CqrsContext(context.Request.Path.Value, path, CqrsType.Command, info.QueryHandlerType);
dynamic result;
if (info.IsAsync)
{
result = await handler.HandleAsync(query, context.RequestAborted);
}
else
{
result = handler.Handle(query);
}
string json = null;
if (result != null)
{
json = result is string?result : await formatter.SerializeAsync(result, context.Request);
}
context.Response.ContentType = formatter.ContentType;
if (json != null)
{
context.Response.StatusCode = (int)HttpStatusCode.OK;
await context.Response.WriteAsync(json, context.RequestAborted);
}
else
{
context.Response.StatusCode = (int)HttpStatusCode.NoContent;
}
}
public QueryHandlerMiddleware(CqrsFormatterRegistry registry, ICqrsOptions options)
{
_registry = registry;
_options = options;
_queryTypes = new Lazy <Dictionary <string, QueryInfo> >(() => options.GetQueryTypes()
.SelectMany(x => x.HttpMethods, (ci, method) => new { QueryInfo = ci, HttpMethod = method })
.ToDictionary(
keySelector: (x) => $"{x.HttpMethod} {options.GetQueryPath(x.QueryInfo)}",
elementSelector: x => x.QueryInfo,
comparer: StringComparer.OrdinalIgnoreCase));
}
private async Task HandleCommand(HttpContext context, ICqrsOptions options)
{
var path = options.GetCommandPath(context.Request.Path.Value);
if (!_commandTypes.ContainsKey(path))
{
throw new CommandNotFoundException($"Command '{path}' not found");
}
dynamic result = null;
var info = _commandTypes[path];
var commandData = await new StreamReader(context.Request.Body).ReadToEndAsync();
dynamic command = DeserializeCommand(commandData, info.CommandType);
dynamic handler = _container.GetInstance(info.CommandHandlerType);
context.Items[ContextKey] = new CqrsContext(context.Request.Path.Value, path, CqrsType.Command, info.CommandHandlerType);
if (info.IsGeneric)
{
if (info.IsAsync)
{
result = await handler.HandleAsync(command, context.RequestAborted);
}
else
{
result = handler.Handle(command);
}
}
else
{
if (info.IsAsync)
{
await handler.HandleAsync(command, context.RequestAborted);
}
else
{
handler.Handle(command);
}
}
CloseSession();
var json = result is string?result : JsonConvert.SerializeObject(result, _jsonSerializerSettings);
context.Response.ContentType = ContentType;
context.Response.StatusCode = (int)HttpStatusCode.OK;
await HttpResponseWritingExtensions.WriteAsync(context.Response, json, context.RequestAborted);
}
public CommandInfo(Type commandType, ICqrsOptions options)
{
CommandType = commandType;
IsAsync = typeof(IAsyncCommand).IsAssignableFrom(commandType) ||
commandType.GetTypeInfo().IsAssignableToGenericType(typeof(IAsyncCommand <>));
IsGeneric = commandType.GetTypeInfo().IsAssignableToGenericType(typeof(ICommand <>)) ||
commandType.GetTypeInfo().IsAssignableToGenericType(typeof(IAsyncCommand <>));
GenericTypes = new[] { CommandType };
HttpMethods = commandType
.GetCustomAttributes(true)
.OfType <HttpMethodAttribute>()
.SelectMany(x => x.HttpMethods)
.Distinct()
.ToArray();
if (!HttpMethods.Any())
{
HttpMethods = options.DefaultCommandHttpMethods;
}
if (IsGeneric)
{
ResultType = DetermineResultTypes(commandType, IsAsync).Single();
GenericTypes = GenericTypes.Union(new[] { ResultType }).ToArray();
}
if (IsAsync)
{
if (IsGeneric)
{
CommandHandlerType = typeof(IAsyncCommandHandler <,>).MakeGenericType(GenericTypes);
}
else
{
CommandHandlerType = typeof(IAsyncCommandHandler <>).MakeGenericType(GenericTypes);
}
}
else
{
if (IsGeneric)
{
CommandHandlerType = typeof(ICommandHandler <,>).MakeGenericType(GenericTypes);
}
else
{
CommandHandlerType = typeof(ICommandHandler <>).MakeGenericType(GenericTypes);
}
}
}
public CqrsMiddleware(Container container, ICqrsOptions options)
{
_container = container;
_options = options;
_jsonSerializerSettings = options.GetJsonSerializerSettings();
_commandTypes = options.GetCommandTypes().ToDictionary(
keySelector: options.GetCommandKey,
elementSelector: type => type,
comparer: StringComparer.OrdinalIgnoreCase);
_queryTypes = options.GetQueryTypes().ToDictionary(
keySelector: options.GetQueryKey,
elementSelector: info => info,
comparer: StringComparer.OrdinalIgnoreCase);
}
public CqrsMiddleware(Container container, CqrsFormatterRegistry registry, ICqrsOptions options)
{
_container = container;
_registry = registry;
_options = options;
_commandTypes = new Lazy <Dictionary <string, CommandInfo> >(() => options.GetCommandTypes().ToDictionary(
keySelector: options.GetCommandKey,
elementSelector: type => type,
comparer: StringComparer.OrdinalIgnoreCase));
_queryTypes = new Lazy <Dictionary <string, QueryInfo> >(() => options.GetQueryTypes().ToDictionary(
keySelector: options.GetQueryKey,
elementSelector: info => info,
comparer: StringComparer.OrdinalIgnoreCase));
}
private async Task HandleQuery(HttpContext context, ICqrsOptions options)
{
var path = options.GetQueryPath(context.Request.Path.Value);
if (!_queryTypes.ContainsKey(path))
{
throw new QueryNotFoundException($"Query '{path}' not found");
}
// GET operations get their data through the query string, while POST operations expect a JSON
// object being put in the body.
var queryData = context.Request.Method == HttpMethod.Get.Method
? SerializationHelpers.ConvertQueryStringToJson(context.Request.QueryString.Value)
: await new StreamReader(context.Request.Body).ReadToEndAsync();
var info = _queryTypes[path];
var query = DeserializeQuery(queryData, info.QueryType);
dynamic handler = _container.GetInstance(info.QueryHandlerType);
context.Items[ContextKey] = new CqrsContext(context.Request.Path.Value, path, CqrsType.Command, info.QueryHandlerType);
dynamic result;
if (info.IsAsync)
{
result = await handler.HandleAsync(query, context.RequestAborted);
}
else
{
result = handler.Handle(query);
}
var json = result is string?result : JsonConvert.SerializeObject(result, _jsonSerializerSettings);
context.Response.ContentType = ContentType;
context.Response.StatusCode = (int)HttpStatusCode.OK;
await HttpResponseWritingExtensions.WriteAsync(context.Response, json, context.RequestAborted);
}
