Google App Engine JDO Persistence Manager and 500 server error - google-app-engine

I keep getting a 500 error everytime to run my service, since the google message tells mme almost nothing i began uploading the service and commenting parts out. It seems to work fine with out using the JDO persistence manager object. It would be great if someone can take a quick look at my code and tell me if I am using the JDO Persistence Manager wrong. This would help me alot.
#Path("/surveymakerpro/")
public class SurveyResource {
// JDO Persistence object
private PersistenceManager surveyDataStore = SurveyPersistenceManagerFactory
.get().getPersistenceManager();
#GET
#Produces({ "application/xml", "application/json" })
#Path("/survey/{surveyName}/")
public Survey getSurvey(#PathParam("surveyName") String surveyName) {
Survey e = surveyDataStore.getObjectById(Survey.class, surveyName);
return e;
}
#GET
#Produces({ "application/xml", "application/json" })
#Path("/allsurveys")
public SurveyNames getListOfSurveys() {
//test code
SurveyQuestion one = new SurveyQuestion();
one.setAnswer("Yes");
one.setId(3);
one.setQuestion("Do you like cake?");
SurveyQuestion two = new SurveyQuestion();
two.setAnswer("Yes");
two.setId(3);
two.setQuestion("Do you like cake?");
List<SurveyConverter> sur = new ArrayList<SurveyConverter>();
sur.add(new SurveyConverter(one));
sur.add(new SurveyConverter(two));
Survey surv = new Survey(sur);
surv.setSurveyName("Test Survey");
Survey survv = new Survey(sur);
survv.setSurveyName("sdd");
surveyDataStore.makePersistent(surv);
surveyDataStore.makePersistent(survv);
//test code
List<String> surveyNames = new ArrayList<String>();
Extent<Survey> extent = surveyDataStore.getExtent(Survey.class, false);
for (Survey survey : extent) {
surveyNames.add(survey.getSurveyName());
}
extent.closeAll();
SurveyNames surveyName = new SurveyNames(surveyNames);
surveyDataStore.close();
return surveyName;
}
#POST
#Consumes({ MediaType.APPLICATION_XML })
#Path("/addSurvey")
public void addSurvey(Survey survey) {
surveyDataStore.makePersistent(survey);
}
// This method gets a survey object stores its data into a TakenSurvey
// object and stores it
// in the Google data store.
#POST
#Consumes({ MediaType.APPLICATION_XML })
#Path("/addTakenSurvey")
public void addTakenSurvey(Survey survey) {
List<SurveyConverter> surveyConverter = survey.getSurvey();
TakenSurvey takenSurvey = new TakenSurvey();
for (SurveyConverter s : surveyConverter) {
TakenSurveyQuestion tsq = new TakenSurveyQuestion(s.getId(),
s.getQuestion(), s.getAnswer());
takenSurvey.getSurvey().add(tsq);
}
surveyDataStore.makePersistent(takenSurvey);
}
#GET
#Produces({ "application/xml", "application/json" })
#Path("/analysis/{surveyName}/{question}/")
public SurveyDataConverter analyzeSurveys(
#PathParam("surveyName") String surveyName,
#PathParam("question") String questionNum) {
Extent<TakenSurvey> extent = surveyDataStore.getExtent(
TakenSurvey.class, false);
List<TakenSurvey> takenSurveys = new ArrayList<TakenSurvey>();
for (TakenSurvey ts : extent) {
if (ts.getSurveyName().equals(surveyName)) {
takenSurveys.add(ts);
}
}
extent.closeAll();
SurveyAnalyzer analyze = new SurveyAnalyzer(takenSurveys);
analyze.getData();
SurveyData data = analyze.getSurveyData(Integer.parseInt(questionNum));
return new SurveyDataConverter(data);
}
// remove survey
// remove taken survey
}

Don't expect the error page to give you a stacktrace - that would be extremely bad practice for both security and usability reasons. Instead, exceptions are logged in the App Engine admin console, under 'logging'. The stacktrace there will tell you what's wrong; if you still can't figure it out, update your question to include it so we can help further.

Related

How to save app data after restart of an app - flutter?

I was wondering how to make my app save data after restart? (The user can delete task and add new task to list, as well as check the box that the task is done. I want the app to save this data so when the user exists the app it will display all the tasks that he left the app with)
I was reading on google for few hours now, I got to
[1]: https://flutter.dev/docs/cookbook/persistence/reading-writing-files
This link as someone recommended on a similar post. But after reading it through I am a bit confused about where to start with my app.
Including some of my code and if you could help me I would really appreciate it as after hours of reading and watching tutorials I am still quite unsure where to start or which way of doing this is best.
My main.dart is this
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return ChangeNotifierProvider(
create: (context) =>
TaskData(), //changing builder: to create: fixed the errors i been having
child: MaterialApp(
home: TasksScreen(),
),
);
}
}
class TaskData extends ChangeNotifier {
List<Task> _tasks = [
Task(name: "Sample task 1"),
Task(name: "Sample task 2"),
Task(name: "Sample task 3"),
];
UnmodifiableListView<Task> get tasks {
return UnmodifiableListView(_tasks);
}
int get taskCount {
return _tasks.length;
}
void addTask(String newTaskTitle) {
final task = Task(name: newTaskTitle);
_tasks.add(task);
notifyListeners();
}
void updateTask(Task task) {
task.toggleDone();
notifyListeners();
}
void deleteTask(Task task) {
_tasks.remove(task);
notifyListeners();
}
Thank you so much!
The basic method is using the device local storage.
1 - Add the shared_preferences in your pubspec.yaml
2 - Create a class to write and read data :
import 'dart:convert';
import 'package:shared_preferences/shared_preferences.dart';
class StoreData {
StoreData._privateConstructor();
static final StoreData instance = StoreData._privateConstructor();
Future<void> saveString(String key, String value) async {
try{
SharedPreferences pref = await SharedPreferences.getInstance();
final encodedValue = base64.encode(utf8.encode(value));
pref.setString(key, encodedValue);
} catch (e){
print('saveString ${e.toString()}');
}
}
Future<String> getString(String key) async {
SharedPreferences pref = await SharedPreferences.getInstance();
final value = pref.getString(key) == null ? '' : pref.getString(key);
if (value.length > 0) {
final decodedValue = utf8.decode(base64.decode(value));
return decodedValue.toString();
}
return '';
}
Future<bool> remove(String key) async {
SharedPreferences pref = await SharedPreferences.getInstance();
return pref.remove(key);
}
}
3 Use :
Save Data:
StoreData.instance.saveString('name', 'sergio');
Retrieve Data:
final String storedName = await StoreData.instance.getString('name');
print('The name is $storedName');
We have many other methods, like use a SQlite, NoSql or a Database in back-end, but the local storage is the most basic case
What you need is a database or a document based data storage. You can store data in a local sqlite db, using sqflite plugin. Or you can store in a JSON asset file.
You can also use a server or cloud service. Firebase is pretty well integrated with flutter, but AWS and Azure are also great.
You can write the data in a text file in the asset, but that would very complicated.

Integration testing with in-memory IdentityServer

I have an API that uses IdentityServer4 for token validation.
I want to unit test this API with an in-memory TestServer. I'd like to host the IdentityServer in the in-memory TestServer.
I have managed to create a token from the IdentityServer.
This is how far I've come, but I get an error "Unable to obtain configuration from http://localhost:54100/.well-known/openid-configuration"
The Api uses [Authorize]-attribute with different policies. This is what I want to test.
Can this be done, and what am I doing wrong?
I have tried to look at the source code for IdentityServer4, but have not come across a similar integration test scenario.
protected IntegrationTestBase()
{
var startupAssembly = typeof(Startup).GetTypeInfo().Assembly;
_contentRoot = SolutionPathUtility.GetProjectPath(#"<my project path>", startupAssembly);
Configure(_contentRoot);
var orderApiServerBuilder = new WebHostBuilder()
.UseContentRoot(_contentRoot)
.ConfigureServices(InitializeServices)
.UseStartup<Startup>();
orderApiServerBuilder.Configure(ConfigureApp);
OrderApiTestServer = new TestServer(orderApiServerBuilder);
HttpClient = OrderApiTestServer.CreateClient();
}
private void InitializeServices(IServiceCollection services)
{
var cert = new X509Certificate2(Path.Combine(_contentRoot, "idsvr3test.pfx"), "idsrv3test");
services.AddIdentityServer(options =>
{
options.IssuerUri = "http://localhost:54100";
})
.AddInMemoryClients(Clients.Get())
.AddInMemoryScopes(Scopes.Get())
.AddInMemoryUsers(Users.Get())
.SetSigningCredential(cert);
services.AddAuthorization(options =>
{
options.AddPolicy(OrderApiConstants.StoreIdPolicyName, policy => policy.Requirements.Add(new StoreIdRequirement("storeId")));
});
services.AddSingleton<IPersistedGrantStore, InMemoryPersistedGrantStore>();
services.AddSingleton(_orderManagerMock.Object);
services.AddMvc();
}
private void ConfigureApp(IApplicationBuilder app)
{
app.UseIdentityServer();
JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();
var options = new IdentityServerAuthenticationOptions
{
Authority = _appsettings.IdentityServerAddress,
RequireHttpsMetadata = false,
ScopeName = _appsettings.IdentityServerScopeName,
AutomaticAuthenticate = false
};
app.UseIdentityServerAuthentication(options);
app.UseMvc();
}
And in my unit-test:
private HttpMessageHandler _handler;
const string TokenEndpoint = "http://localhost/connect/token";
public Test()
{
_handler = OrderApiTestServer.CreateHandler();
}
[Fact]
public async Task LeTest()
{
var accessToken = await GetToken();
HttpClient.SetBearerToken(accessToken);
var httpResponseMessage = await HttpClient.GetAsync("stores/11/orders/asdf"); // Fails on this line
}
private async Task<string> GetToken()
{
var client = new TokenClient(TokenEndpoint, "client", "secret", innerHttpMessageHandler: _handler);
var response = await client.RequestClientCredentialsAsync("TheMOON.OrderApi");
return response.AccessToken;
}
You were on the right track with the code posted in your initial question.
The IdentityServerAuthenticationOptions object has properties to override the default HttpMessageHandlers it uses for back channel communication.
Once you combine this with the CreateHandler() method on your TestServer object you get:
//build identity server here
var idBuilder = new WebBuilderHost();
idBuilder.UseStartup<Startup>();
//...
TestServer identityTestServer = new TestServer(idBuilder);
var identityServerClient = identityTestServer.CreateClient();
var token = //use identityServerClient to get Token from IdentityServer
//build Api TestServer
var options = new IdentityServerAuthenticationOptions()
{
Authority = "http://localhost:5001",
// IMPORTANT PART HERE
JwtBackChannelHandler = identityTestServer.CreateHandler(),
IntrospectionDiscoveryHandler = identityTestServer.CreateHandler(),
IntrospectionBackChannelHandler = identityTestServer.CreateHandler()
};
var apiBuilder = new WebHostBuilder();
apiBuilder.ConfigureServices(c => c.AddSingleton(options));
//build api server here
var apiClient = new TestServer(apiBuilder).CreateClient();
apiClient.SetBearerToken(token);
//proceed with auth testing
This allows the AccessTokenValidation middleware in your Api project to communicate directly with your In-Memory IdentityServer without the need to jump through hoops.
As a side note, for an Api project, I find it useful to add IdentityServerAuthenticationOptions to the services collection in Startup.cs using TryAddSingleton instead of creating it inline:
public void ConfigureServices(IServiceCollection services)
{
services.TryAddSingleton(new IdentityServerAuthenticationOptions
{
Authority = Configuration.IdentityServerAuthority(),
ScopeName = "api1",
ScopeSecret = "secret",
//...,
});
}
public void Configure(IApplicationBuilder app)
{
var options = app.ApplicationServices.GetService<IdentityServerAuthenticationOptions>()
app.UseIdentityServerAuthentication(options);
//...
}
This allows you to register the IdentityServerAuthenticationOptions object in your tests without having to alter the code in the Api project.
I understand there is a need for a more complete answer than what #james-fera posted. I have learned from his answer and made a github project consisting of a test project and API project. The code should be self-explanatory and not hard to understand.
https://github.com/emedbo/identityserver-test-template
The IdentityServerSetup.cs class https://github.com/emedbo/identityserver-test-template/blob/master/tests/API.Tests/Config/IdentityServerSetup.cs can be abstracted away e.g. NuGetted away, leaving the base class IntegrationTestBase.cs
The essences is that can make the test IdentityServer work just like a normal IdentityServer, with users, clients, scopes, passwords etc. I have made the DELETE method [Authorize(Role="admin)] to prove this.
Instead of posting code here, I recommend read #james-fera's post to get the basics then pull my project and run tests.
IdentityServer is such a great tool, and with the ability to use the TestServer framework it gets even better.
I think you probably need to make a test double fake for your authorization middleware depending on how much functionality you want. So basically you want a middleware that does everything that the Authorization middleware does minus the back channel call to the discovery doc.
IdentityServer4.AccessTokenValidation is a wrapper around two middlewares. The JwtBearerAuthentication middleware, and the OAuth2IntrospectionAuthentication middleware. Both of these grab the discovery document over http to use for token validation. Which is a problem if you want to do an in-memory self-contained test.
If you want to go through the trouble you will probably need to make a fake version of app.UseIdentityServerAuthentication that doesnt do the external call that fetches the discovery document. It only populates the HttpContext principal so that your [Authorize] policies can be tested.
Check out how the meat of IdentityServer4.AccessTokenValidation looks here. And follow up with a look at how JwtBearer Middleware looks here
We stepped away from trying to host a mock IdentityServer and used dummy/mock authorizers as suggested by others here.
Here's how we did that in case it's useful:
Created a function which takes a type, creates a test Authentication Middleware and adds it to the DI engine using ConfigureTestServices (so that it's called after the call to Startup.)
internal HttpClient GetImpersonatedClient<T>() where T : AuthenticationHandler<AuthenticationSchemeOptions>
{
var _apiFactory = new WebApplicationFactory<Startup>();
var client = _apiFactory
.WithWebHostBuilder(builder =>
{
builder.ConfigureTestServices(services =>
{
services.AddAuthentication("Test")
.AddScheme<AuthenticationSchemeOptions, T>("Test", options => { });
});
})
.CreateClient(new WebApplicationFactoryClientOptions
{
AllowAutoRedirect = false,
});
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Test");
return client;
}
Then we create what we called 'Impersonators' (AuthenticationHandlers) with the desired roles to mimic users with roles (We actually used this as a base class, and create derived classes based on this to mock different users):
public abstract class FreeUserImpersonator : AuthenticationHandler<AuthenticationSchemeOptions>
{
public Impersonator(
IOptionsMonitor<AuthenticationSchemeOptions> options,
ILoggerFactory logger, UrlEncoder encoder, ISystemClock clock)
: base(options, logger, encoder, clock)
{
base.claims.Add(new Claim(ClaimTypes.Role, "FreeUser"));
}
protected List<Claim> claims = new List<Claim>();
protected override Task<AuthenticateResult> HandleAuthenticateAsync()
{
var identity = new ClaimsIdentity(claims, "Test");
var principal = new ClaimsPrincipal(identity);
var ticket = new AuthenticationTicket(principal, "Test");
var result = AuthenticateResult.Success(ticket);
return Task.FromResult(result);
}
}
Finally, we can perform our integration tests as follows:
// Arrange
HttpClient client = GetImpersonatedClient<FreeUserImpersonator>();
// Act
var response = await client.GetAsync("api/things");
// Assert
Assert.That.IsSuccessful(response);
Test API startup:
public class Startup
{
public static HttpMessageHandler BackChannelHandler { get; set; }
public void Configuration(IAppBuilder app)
{
//accept access tokens from identityserver and require a scope of 'Test'
app.UseIdentityServerBearerTokenAuthentication(new IdentityServerBearerTokenAuthenticationOptions
{
Authority = "https://localhost",
BackchannelHttpHandler = BackChannelHandler,
...
});
...
}
}
Assigning the AuthServer.Handler to TestApi BackChannelHandler in my unit test project:
protected TestServer AuthServer { get; set; }
protected TestServer MockApiServer { get; set; }
protected TestServer TestApiServer { get; set; }
[OneTimeSetUp]
public void Setup()
{
...
AuthServer = TestServer.Create<AuthenticationServer.Startup>();
TestApi.Startup.BackChannelHandler = AuthServer.CreateHandler();
TestApiServer = TestServer.Create<TestApi.Startup>();
}
The trick is to create a handler using the TestServer that is configured to use IdentityServer4. Samples can be found here.
I created a nuget-package available to install and test using the Microsoft.AspNetCore.Mvc.Testing library and the latest version of IdentityServer4 for this purpose.
It encapsulates all the infrastructure code necessary to build an appropriate WebHostBuilder which is then used to create a TestServer by generating the HttpMessageHandler for the HttpClient used internally.
None of the other answers worked for me because they rely on 1) a static field to hold your HttpHandler and 2) the Startup class to have knowledge that it may be given a test handler. I've found the following to work, which I think is a lot cleaner.
First create an object that you can instantiate before your TestHost is created. This is because you won't have the HttpHandler until after the TestHost is created, so you need to use a wrapper.
public class TestHttpMessageHandler : DelegatingHandler
{
private ILogger _logger;
public TestHttpMessageHandler(ILogger logger)
{
_logger = logger;
}
protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
_logger.Information($"Sending HTTP message using TestHttpMessageHandler. Uri: '{request.RequestUri.ToString()}'");
if (WrappedMessageHandler == null) throw new Exception("You must set WrappedMessageHandler before TestHttpMessageHandler can be used.");
var method = typeof(HttpMessageHandler).GetMethod("SendAsync", BindingFlags.Instance | BindingFlags.NonPublic);
var result = method.Invoke(this.WrappedMessageHandler, new object[] { request, cancellationToken });
return await (Task<HttpResponseMessage>)result;
}
public HttpMessageHandler WrappedMessageHandler { get; set; }
}
Then
var testMessageHandler = new TestHttpMessageHandler(logger);
var webHostBuilder = new WebHostBuilder()
...
services.PostConfigureAll<JwtBearerOptions>(options =>
{
options.Audience = "http://localhost";
options.Authority = "http://localhost";
options.BackchannelHttpHandler = testMessageHandler;
});
...
var server = new TestServer(webHostBuilder);
var innerHttpMessageHandler = server.CreateHandler();
testMessageHandler.WrappedMessageHandler = innerHttpMessageHandler;

Nancy testing GetModel<T> throws KeyNotFoundException

I'm trying to test that the model returned from my Nancy application is as expected. I have followed the docs here but whenever I call the GetModel<T> extension method it throws a KeyNotFoundException.
System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
I know what the error means but I'm failing to see why it's being thrown.
Here's my module
public class SanityModule : NancyModule
{
public SanityModule()
{
Get["sanity-check"] = _ => Negotiate.WithModel(new SanityViewModel { Id = 1 })
.WithStatusCode(HttpStatusCode.OK);
}
}
my view model
public class SanityViewModel
{
public int Id { get; set; }
}
and here's my test
[TestFixture]
public class SanityModuleTests
{
[Test]
public void Sanity_Check()
{
// Arrange
var browser = new Browser(with =>
{
with.Module<SanityModule>();
with.ViewFactory<TestingViewFactory>();
});
// Act
var result = browser.Get("/sanity-check", with =>
{
with.HttpRequest();
with.Header("accept", "application/json");
});
var model = result.GetModel<SanityViewModel>();
// Asset
model.Id.ShouldBeEquivalentTo(1);
}
}
Debugging this test shows that the module is hit and completes just fine. Running the application shows that the response is as expected.
Can anyone shed some light on this?
Thanks to the lovely guys, albertjan and the.fringe.ninja, in the Nancy Jabbr room we've got an explanation as to what's going on here.
TL;DR It makes sense for this to not work but the error message should be more descriptive. There is a workaround below.
The issue here is that I am requesting the response as application/json whilst using TestingViewFactory.
Let's take a look at the implementation of GetModel<T>();
public static TType GetModel<TType>(this BrowserResponse response)
{
return (TType)response.Context.Items[TestingViewContextKeys.VIEWMODEL];
}
This is simply grabbing the view model from the NancyContext and casting it to your type. This is where the error is thrown, as there is no view model in NancyContext. This is because the view model is added to NancyContext in the RenderView method of TestingViewFactory.
public Response RenderView(string viewName, dynamic model, ViewLocationContext viewLocationContext)
{
// Intercept and store interesting stuff
viewLocationContext.Context.Items[TestingViewContextKeys.VIEWMODEL] = model;
viewLocationContext.Context.Items[TestingViewContextKeys.VIEWNAME] = viewName;
viewLocationContext.Context.Items[TestingViewContextKeys.MODULENAME] = viewLocationContext.ModuleName;
viewLocationContext.Context.Items[TestingViewContextKeys.MODULEPATH] = viewLocationContext.ModulePath;
return this.decoratedViewFactory.RenderView(viewName, model, viewLocationContext);
}
My test is requesting json so RenderView will not be called. This means you can only use GetModel<T> if you use a html request.
Workaround
My application is an api so I do not have any views so changing the line
with.Header("accept", "application/json");
to
with.Header("accept", "text/html");
will throw a ViewNotFoundException. To avoid this I need to implement my own IViewFactory. (this comes from the.fringe.ninja)
public class TestViewFactory : IViewFactory
{
#region IViewFactory Members
public Nancy.Response RenderView(string viewName, dynamic model, ViewLocationContext viewLocationContext)
{
viewLocationContext.Context.Items[Fixtures.SystemUnderTest.ViewModelKey] = model;
return new HtmlResponse();
}
#endregion
}
Then it is simply a case of updating
with.ViewFactory<TestingViewFactory>();
to
with.ViewFactory<TestViewFactory>();
Now GetModel<T> should work without needing a view.

Error 404 when calling Google Cloud Endpoint API from Google Apps Script

I am trying to call a Google Cloud Endpoint API (developed on App Engine) via Google Apps Script. The endpoint is up and running, honestly I don't know which URL I should use but through Google Chrome Web Tools it looks like the URL is something like:
https://myapp.appspot.com/_ah/api/myendpointapi/v1/myEndPointMethod/
Along with API parameters directly included in the URL, separeted by slashes:
https://myapp.appspot.com/_ah/api/myendpointapi/v1/myEndPointMethod/param1value/param2value/...
Now, in order to call that API from Google App Script I am using the following code snippet:
function myFunction() {
var params =
{
"param1" : "param1value",
"param2" : "param2value",
};
var result = UrlFetchApp.fetch('https://myapp.appspot.com/_ah/api/myendpointapi/v1/myEndPointMethod/', params);
DocumentApp.getUi().alert(result);
}
However I always get a 404 error. If I have to be honest I don't even know if UrlFetchApp is the correct way of calling the API. I noticed this thread on StackOverflow but no one answered. What's the correct URL to use? Many thanks.
EDIT: Now I am trying with an API method which does not require any parameter. I found a way to call a specific URL (using method='get' as suggested by the answer below) but now I get a 401 error because it says I am not logged in. I believe I need to use some kind of OAuth parameter now. Any idea? I tryed using OAuthConfig but no luck with that as well :( From App Engine logs I can see the following error:
com.google.api.server.spi.auth.GoogleIdTokenUtils verifyToken: verifyToken: null
com.google.api.server.spi.auth.AppEngineAuthUtils getIdTokenEmail:
getCurrentUser: idToken=null
function myFunction() {
var result = UrlFetchApp.fetch('myurl', googleOAuth_());
result = result.getContentText();
}
function googleOAuth_() {
var SCOPE = 'https://www.googleapis.com/auth/drive';
var NAME = 'myAPIName';
var oAuthConfig = UrlFetchApp.addOAuthService(NAME);
oAuthConfig.setRequestTokenUrl('https://www.google.com/accounts/OAuthGetRequestToken?scope='+SCOPE);
oAuthConfig.setAuthorizationUrl('https://www.google.com/accounts/OAuthAuthorizeToken');
oAuthConfig.setAccessTokenUrl('https://www.google.com/accounts/OAuthGetAccessToken');
oAuthConfig.setConsumerKey('anonymous');
oAuthConfig.setConsumerSecret('anonymous');
return {oAuthServiceName:NAME, oAuthUseToken:'always'};
}
UrlFetchApp is the only way to call a Google Cloud Endpoints API at the moment. The second parameter to UrlFetchApp.fetch is a special key-value map of advanced options. To pass POST parameters, you need to do the following:
UrlFetchApp.fetch(url, {
method: 'post',
payload: {
"param1" : "param1value",
"param2" : "param2value",
}
});
I was fighting a similar (not the same) problem, when testing feasibility of a GCM backed by EndPoints server. Basically testing if it is possible to get the Google Spreadsheet Appscript to send notification to an Android device. Please bear with me, the following explanation may be a bit convoluted;
Starting with a standard 'Cloud Messaging for Android', backed by the 'App Engine Backend with Google Cloud Messaging', I managed to build a test system that would send messages between Android devices (Github here).
Here is a VERY sparse EndPoints server code that handles register / un-register Android devices, as well as reporting registered devices and sending a message to a list of registered devices.
WARNING: This is not a production quality code, it is stripped of any logging, error handling in order to keep it short.
#Api( name = "gcmEP", version = "v1",
namespace = #ApiNamespace(ownerDomain = "epgcm.example.com", ownerName = "epgcm.example.com", packagePath = "" )
)
public class GcmEP {
#ApiMethod(name = "registToken")
public void registToken(#Named("token") String token) {
if (ofy().load().type(TokenRec.class).filter("token", token).first().now() == null) {
ofy().save().entity(new TokenRec(token)).now();
}
}
#ApiMethod(name = "unregToken")
public void unregToken(#Named("token") String token) {
TokenRec record = ofy().load().type(TokenRec.class).filter("token", token).first().now();
if (record != null) {
ofy().delete().entity(record).now();
}
}
#ApiMethod(name = "listTokens")
public CollectionResponse<TokenRec> listTokens() {
return CollectionResponse.<TokenRec>builder().setItems(ofy().load().type(TokenRec.class).list()).build();
}
#ApiMethod(name = "sendMsg")
public void sendMsg(#Named("message") String message) throws IOException {
if (message != null && message.length() > 0) {
Sender sender = new Sender(System.getProperty("gcm.api.key"));
Message msg = new Message.Builder().addData("message", message).build();
for (TokenRec record : ofy().load().type(TokenRec.class).list()) {
Result result = sender.send(msg, record.getToken(), 4);
if (result.getMessageId() != null) {
// handle CanonicalRegistrationId
} else {
// handle errors, delete record
}
}
}
}
}
Android code for registration and message sending is shown here, even if it is not relevant.
GcmEP mRegSvc;
String mToken;
// register device on EndPoints backend server
private void registerMe() {
new Thread(new RegisterMe(this)).start();
}
private class RegisterMe implements Runnable {
Activity mAct;
public RegisterMe(Activity act) { mAct = act; }
public void run() {
String senderId = null;
if (mAct != null) try {
if (mRegSvc == null) {
mRegSvc = new GcmEP
.Builder(AndroidHttp.newCompatibleTransport(), new AndroidJsonFactory(), null).setRootUrl(UT.ROOT_URL).build();
}
senderId = getString(R.string.gcm_defaultSenderId);
mToken = InstanceID.getInstance(mAct).getToken(senderId, GoogleCloudMessaging.INSTANCE_ID_SCOPE, null);
mRegSvc.registToken(mToken).execute();
GcmPubSub.getInstance(mAct).subscribe(mToken, "/topics/global", null); // subscribing to all 'topics' from 'mToken'
} catch (IOException e) { e.printStackTrace(); }
}
}
// send message to EndPoints backend server
new Thread(new Runnable() {
#Override
public void run() {
if (mRegSvc != null) try {
mRegSvc.sendMsg("hello").execute();
} catch (IOException e) { e.printStackTrace(); }
}
}).start();
// receive GCM message
public class GcmListenSvc extends GcmListenerService {
#Override
public void onMessageReceived(String senderId, Bundle data) {
Log.i("_X_", data.getString("message"));
}
}
What is relevant, thought, there is also an APIs Explorer created for the project, that can be used to send messages to your Android device from any browser.
If you use this Explorer, you can see the GET, POST requests for your EndPoints backend server, i.e.
list all registered devices:
GET https://epgcm.appspot.com/_ah/api/gcmEP/v1/tokenrec?fields=items
send a message to all registered devices:
POST https://epgcm.appspot.com/_ah/api/gcmEP/v1/sendMsg/Hello%20World!
Now, you can use this knowledge to send messages to your Android device from an AppScript code as shown:
Version 1: Get list of registered devices and send a GCM message to all of them (or a filtered set).
function sendMsg() {
var msg = 'test from CODE.GS';
var url = 'https://epgcm.appspot.com/_ah/api/gcmEP/v1/tokenrec?fields=items';
var params = { method : 'get'};
var response = UrlFetchApp.fetch(url, params);
var data = JSON.parse(response.getContentText());
var regIds = [];
for (i in data.items)
regIds.push(data.items[i].token);
var payload = JSON.stringify({
'registration_ids' : regIds,
'data' : { 'message' : msg }
});
var params = {
'contentType' : 'application/json',
'headers' : {'Authorization' : 'key=AIza............................'},
'method' : 'post',
'payload' : payload
};
url = 'https://android.googleapis.com/gcm/send';
UrlFetchApp.fetch(url, params);
}
This version relies on code from an old YouTube video, and I don't know if the call to 'android.googleapis.com' is still supported (but it works).
Version 2: Use the EndPoints's 'sendMsg' directly.
function sendMsg() {
var msg = 'test from CODE.GS';
var params = { method : 'post'};
var url = 'https://demoepgcm.appspot.com/_ah/api/gcmEP/v1/sendMsg/' + encodeURIComponent(msg.trim());
UrlFetchApp.fetch(url, params);
}
I have to admit I've never written a line of JavaScript code before, so it may not be up-to-par, but I made it work as a 'proof of concept'.
I would like to get feedback about this problem from people-who-know, since there is so little published info on this specific issue.

WPF and MVC4 Web API Internal Server Error 500 on POST

So I'm attempting to attach to a web api method via a WPF service, but get only a 500 error on anything other than a GET.
WPF call:
using (var client = new HttpClient())
{
var user = new MyUser
{
EntityID = Guid.NewGuid(),
FirstName = "WPF",
LastName = "test"
};
var formatter = new JsonMediaTypeFormatter();
HttpContent content = new ObjectContent<MyUser>(user, formatter);
client.BaseAddress = new Uri("http://localhost:19527/api/");
var response = await client.PostAsJsonAsync("MyUser", content);
//.ContinueWith((postTask) => result = (postTask.Result.Content == null) ? "Could not create user" : "User created successully!");
var r = response.StatusCode;
}'
...and the receiving controller:
public HttpResponseMessage Get(string badgeId)
{
return Request.CreateResponse<bool>(HttpStatusCode.OK, (service.UserByBadge(badgeId) != null));
}
public HttpResponseMessage Put(MyUser user)
{
return Request.CreateResponse<bool>(HttpStatusCode.OK, service.UpsertUser(user));
}
public HttpResponseMessage Post(MyUser user)
{
if (service.UpsertUser(user)) return Request.CreateResponse<MyUser>(HttpStatusCode.OK, service.Get<MyUser>(u => u.BadgeID == user.BadgeID));
return Request.CreateResponse<MyUser>(HttpStatusCode.NoContent, null);
}'
The service on the WebApi controller is a GenericRepository, which is working fine, since the Get method returns as expected. It's only when I use Post that I get the error. Debugging the methods throws the break point in the Get, but not in the Post, so I don't think it's ever being called.
Here's the route config:
routes.MapRoute(
name: "Default",
url: "api/{controller}/{action}/{id}",
defaults: new { controller = "{controller}", action = "{action}", id = UrlParameter.Optional }
);
I've tried different examples from other SO posts, but none appear to address this issue specifically. I'm guessing there's something wrong with how I've constructed the Post() method?
================================================================
RESOLUTION: Model being passed was failing property validations. Why this was causing a 500, not certain. But once I solved for this, API method began working.
If anybody has a "why" explanation, would love to know for future reference.

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