public HandlerContext(RestRequest request, ReadOnlyDictionary<String, String> env, MethodInfo code)
{
Request = request.AssertNotNull();
Env = env.AssertNotNull();
Code = code.AssertNotNull();
// todo:
// 1) allow to return void, json, string, byte[], stream and any other object (the latter will then be serialized to json)
// 2) allow non-statics
// 3) allow RestRequest, RestResponse, RestContext, RestHints, Query, RequestHeaders, ResponseHeaders, Cookies, dynamic/Json (Data), Stream (output stream), TextWriter (response)
// 4) allow config types
// 5) deserialize when binding
// 6) bind to fields as well
// 7) comprehensive logging
// 8) try to bind everything, rather than stop at first error
Debug.EnsureBlankLine();
Debug.WriteLine(" * Env: {0}", Env.Select(kvp => String.Format("{0} = {1}", kvp.Key, kvp.Value)).StringJoin());
Debug.WriteLine(" * Query: {0}", request.Query.Select(kvp => String.Format("{0} = {1}", kvp.Key, (String)kvp.Value)).StringJoin().Fluent(s => s.IsEmpty() ? "<empty>" : s));
Debug.WriteLine(" * Data: {0}", ((Json)request.Data).ToCompactString().Fluent(s => s.IsEmpty() ? "<empty>" : s));
// todo. after that log:
// Write(" * field foo <= ")
// do something, then write either:
// 1) WriteLine("Data.foo") or
// 2) WriteLine("FAIL") or even
// 3) exception.... [will be traced by RestGateway]
}
public RestContext(HttpContext native)
{
_native = native;
_req = new RestRequest(this);
_resp = new RestResponse(this);
_hints = new RestHints(this);
native.Items["XenoGears.RestContext"] = this;
}
public DispatchContext(RestRequest req)
{
Info.EnsureBlankLine();
Info.Write("Dispatching request ");
var snippets = SnippetRegistry.Methods<RestResourceAttribute>();
Info.WriteLine("(across {0} handlers)...", snippets.Count());
BindResults = snippets.Select(snippet => new BindContext(req, snippet)).ToReadOnly();
// todo. maybe invent some novel way to do dispatch
// so that "http://localhost/daas/ldab/Users?$filter=substringof('Bu', Name)"
// doesn't get dispatched to "/{relativeFilePath}" and cause a crash with 400
// but rather becomes a 404 because it's just "/daas/ldap/{s_dataQuery}" with a typo
var bestMatch = PickBestMatch(BindResults);
if (bestMatch == null)
{
if (BindResults.Any(r => r.Result == BindResult.UrlMismatch)) Result = DispatchResult.UrlMismatch;
if (BindResults.Any(r => r.Result == BindResult.ArgsMismatch)) Result = DispatchResult.ArgsMismatch;
if (BindResults.Any(r => r.Result == BindResult.MethodMismatch)) Result = DispatchResult.MethodNotAllowed;
if (BindResults.Any(r => r.Result == BindResult.NotAuthenticated)) Result = DispatchResult.NotAuthenticated;
if (BindResults.Any(r => r.Result == BindResult.NotAuthorized)) Result = DispatchResult.NotAuthorized;
if (BindResults.Count(r => r.Result == BindResult.Success) > 1) Result = DispatchResult.Ambiguous;
}
else
{
BestMatch = bestMatch;
Result = (DispatchResult)Enum.Parse(typeof(DispatchResult), bestMatch.Result.ToString());
}
Info.EnsureBlankLine();
Info.WriteLine("Dispatch summary: {0}", Result);
Info.WriteLine(BindResults.Select(r => " * " + r.ToString()).StringJoin(Environment.NewLine));
Info.EnsureBlankLine();
if (Result != DispatchResult.Success) Error.WriteLine("Dispatch has failed with status code {0}", Result.ToHttpStatusCode());
else Info.WriteLine("Bound handler: {0}", BestMatch.HandlerContext);
}
public BindContext(RestRequest request, Snippet<MethodInfo> snippet)
{
Request = request.AssertNotNull();
Snippet = snippet.AssertNotNull();
Debug.EnsureBlankLine();
Debug.WriteLine("Binding request to {0}...", snippet.Member.GetCSharpRef(ToCSharpOptions.InformativeWithNamespaces));
var asmUri = AsmResource.Uri ?? String.Empty;
var typeUri = TypeResource.Uri ?? String.Empty;
var methodUri = MethodResource.Uri ?? String.Empty;
var uriTemplate = asmUri + typeUri + methodUri;
ResourceTemplate = uriTemplate;
Debug.WriteLine(" * Resource template: {0}", ResourceTemplate);
var parsed1 = new Url(request.Resource).Parse(uriTemplate);
var parsed2 = new Url(request.Resource + "/").Parse(uriTemplate);
var parsed = parsed1 ?? parsed2;
Resource = request.Resource;
ParsedResource = parsed;
Debug.WriteLine(" * Resource: {0}", Resource);
if (parsed != null)
{
Debug.WriteLine(" + Resource matches the template");
var code = snippet.Member;
HandlerCode = code;
HandlerContext = new HandlerContext(request, parsed, code);
Handler = () =>
{
HandlerContext.Validate().AssertTrue();
var result = HandlerContext.Invoke();
var response = request.Response;
var is_json = request["Content-Type"] == "application/json";
if (is_json) response.Succeed(new Json(result));
else response.Succeed(result);
};
if (HandlerContext.Validate())
{
Debug.WriteLine(" + Handler arguments are bound successfully");
var asmMethods = AsmResource.Allow;
var typeMethods = TypeResource.Allow;
var methodMethods = MethodResource.Allow;
var allowedMethods = asmMethods & typeMethods & methodMethods;
AllowedMethods = allowedMethods;
Debug.WriteLine(" * Allowed HTTP methods: " + AllowedMethods);
var allowMethod = false;
allowMethod |= (request.Method == "GET" && ((allowedMethods & RestMethods.Get) != 0));
allowMethod |= (request.Method == "PUT" && ((allowedMethods & RestMethods.Put) != 0));
allowMethod |= (request.Method == "POST" && ((allowedMethods & RestMethods.Post) != 0));
allowMethod |= (request.Method == "MERGE" && ((allowedMethods & RestMethods.Merge) != 0));
allowMethod |= (request.Method == "DELETE" && ((allowedMethods & RestMethods.Delete) != 0));
Method = request.Method;
Debug.WriteLine(" * HTTP method: " + Method);
if (allowMethod)
{
Debug.WriteLine(" + HTTP method is allowed");
var authenticators = SnippetRegistry.Methods<AuthenticationFilterAttribute>();
var skipAuthentication = AsmResource.SkipAuthentication || TypeResource.SkipAuthentication || MethodResource.SkipAuthentication;
var boundAuthenticators = authenticators.Select(authenticator =>
{
Debug.WriteLine(" * Authorizing against {0}...", authenticator.Member.GetCSharpRef(ToCSharpOptions.InformativeWithNamespaces));
return new HandlerContext(request, parsed, authenticator.Member);
}).ToReadOnly();
var authenticated = skipAuthentication || boundAuthenticators.All(authenticator => authenticator.Validate() && Equals(authenticator.Invoke(), true));
if (authenticated)
{
Debug.WriteLine(" + Authentication successful");
var authorizers = SnippetRegistry.Methods<AuthorizationFilterAttribute>();
var skipAuthorization = AsmResource.SkipAuthorization || TypeResource.SkipAuthorization || MethodResource.SkipAuthorization;
var boundAuthorizers = authorizers.Select(authorizer =>
{
Debug.WriteLine(" * Authorizing against {0}...", authorizer.Member.GetCSharpRef(ToCSharpOptions.InformativeWithNamespaces));
return new HandlerContext(request, parsed, authorizer.Member);
}).ToReadOnly();
var authorized = skipAuthorization || boundAuthorizers.All(authorizer => authorizer.Validate() && Equals(authorizer.Invoke(), true));
if (authorized)
{
Debug.WriteLine(" + Authorization successful");
Debug.WriteLine(" * Bind successful");
Result = BindResult.Success;
}
else
{
Debug.WriteLine(" FAIL => Failed to authorize");
Result = BindResult.NotAuthorized;
}
}
else
{
Debug.WriteLine(" FAIL => Failed to authenticate");
Result = BindResult.NotAuthenticated;
}
}
else
{
Debug.WriteLine(" FAIL => HTTP method is not allowed");
Result = BindResult.MethodMismatch;
}
}
else
{
Debug.WriteLine(" FAIL => Failed to bind handler arguments");
Result = BindResult.ArgsMismatch;
}
}
else
{
Debug.WriteLine("FAIL => Resource doesn't match the template");
Result = BindResult.UrlMismatch;
}
}
