IIS: get system CPU usage from web api application - iis

I have to create a small service, to show health status of the machine (Windwos service).
I created a very small and simple aspnet app, that returns this data.
It works fine when I run the app from command line (using dotnet command), But when I run it as a IIS site, the cpu method doesn't returns any value.
Thanks for any help, and sorry for my bad English.
This is the code:
[ApiController]
[Route("[controller]")]
[Route("/")]
public sealed class SystemHealthController : ControllerBase
{
[HttpGet("cpu")]
public async Task<ActionResult<string>> GetCpu()
=> await WmicMetricsClient.Cpu().ConfigureAwait(false);
[HttpGet("memory")]
public async Task<ActionResult<string>> GetMemory()
=> await WmicMetricsClient.Memory();
}
public static class WmicMetricsClient
{
public static async Task<string> Memory()
{
var output = await GetCommandLineOutputAsync(
fileName: "wmic",
arguments: "OS get FreePhysicalMemory,TotalVisibleMemorySize /Value");
return output;
}
public static async Task<string> Cpu()
{
var output = await GetCommandLineOutputAsync(
fileName: "wmic",
arguments: "cpu get loadpercentage /Value");
return output;
}
private static async Task<string> GetCommandLineOutputAsync(string fileName, string arguments)
{
var info = new ProcessStartInfo
{
FileName = fileName,
Arguments = arguments,
RedirectStandardOutput = true
};
using var process = Process.Start(info);
return await process.StandardOutput.ReadToEndAsync();
}
}

OK, I have the solution:
In the Computer Management>System Tools>Local Usesr and groups>Groups.
then, I click on "Perfomance Monitor Users" group, and add IIS Apppool\MYAPPPOOL.

Related

Testing a Multipart file upload Azure Function

So I have written a simple Azure Function (AF) that accepts (via Http Post method) an IFormCollection, loops through the file collection, pushes each file into an Azure Blob storage container and returns the url to each file.
The function itself works perfectly when I do a single file or multiple file post through Postman using the 'multipart/form-data' header. However when I try to post a file through an xUnit test, I get the following error:
System.IO.InvalidDataException : Multipart body length limit 16384 exceeded.
I have searched high and low for a solution, tried different things, namely;
Replicating the request object to be as close as possible to Postmans request.
Playing around with the 'boundary' in the header.
Setting 'RequestFormLimits' on the function.
None of these have helped so far.
The details are the project are as follows:
Azure Function v3: targeting .netcoreapp3.1
Startup.cs
public class Startup : FunctionsStartup
{
public IConfiguration Configuration { get; private set; }
public override void Configure(IFunctionsHostBuilder builder)
{
var x = builder;
InitializeConfiguration(builder);
builder.Services.AddSingleton(Configuration.Get<UploadImagesAppSettings>());
builder.Services.AddLogging();
builder.Services.AddSingleton<IBlobService,BlobService>();
}
private void InitializeConfiguration(IFunctionsHostBuilder builder)
{
var executionContextOptions = builder
.Services
.BuildServiceProvider()
.GetService<IOptions<ExecutionContextOptions>>()
.Value;
Configuration = new ConfigurationBuilder()
.SetBasePath(executionContextOptions.AppDirectory)
.AddJsonFile("appsettings.json")
.AddJsonFile("appsettings.Development.json", optional: true)
.AddEnvironmentVariables()
.Build();
}
}
UploadImages.cs
public class UploadImages
{
private readonly IBlobService BlobService;
public UploadImages(IBlobService blobService)
{
BlobService = blobService;
}
[FunctionName("UploadImages")]
[RequestFormLimits(ValueLengthLimit = int.MaxValue,
MultipartBodyLengthLimit = 60000000, ValueCountLimit = 10)]
public async Task<IActionResult> Run(
[HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = "images")] HttpRequest req)
{
List<Uri> returnUris = new List<Uri>();
if (req.ContentLength == 0)
{
string badResponseMessage = $"Request has no content";
return new BadRequestObjectResult(badResponseMessage);
}
if (req.ContentType.Contains("multipart/form-data") && req.Form.Files.Count > 0)
{
foreach (var file in req.Form.Files)
{
if (!file.IsValidImage())
{
string badResponseMessage = $"{file.FileName} is not a valid/accepted Image file";
return new BadRequestObjectResult(badResponseMessage);
}
var uri = await BlobService.CreateBlobAsync(file);
if (uri == null)
{
return new ObjectResult($"Could not blob the file {file.FileName}.");
}
returnUris.Add(uri);
}
}
if (!returnUris.Any())
{
return new NoContentResult();
}
return new OkObjectResult(returnUris);
}
}
Exception Thrown:
The below exception is thrown at the second if statement above, when it tries to process req.Form.Files.Count > 0, i.e.
if (req.ContentType.Contains("multipart/form-data") && req.Form.Files.Count > 0) {}
Message:
System.IO.InvalidDataException : Multipart body length limit 16384 exceeded.
Stack Trace:
MultipartReaderStream.UpdatePosition(Int32 read)
MultipartReaderStream.ReadAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
StreamHelperExtensions.DrainAsync(Stream stream, ArrayPool`1 bytePool, Nullable`1 limit, CancellationToken cancellationToken)
MultipartReader.ReadNextSectionAsync(CancellationToken cancellationToken)
FormFeature.InnerReadFormAsync(CancellationToken cancellationToken)
FormFeature.ReadForm()
DefaultHttpRequest.get_Form()
UploadImages.Run(HttpRequest req) line 42
UploadImagesTests.HttpTrigger_ShouldReturnListOfUploadedUris(String fileNames)
xUnit Test Project: targeting .netcoreapp3.1
Over to the xUnit Test project, basically I am trying to write an integration test. The project references the AF project and has the following classes:
TestHost.cs
public class TestHost
{
public TestHost()
{
var startup = new TestStartup();
var host = new HostBuilder()
.ConfigureWebJobs(startup.Configure)
.ConfigureServices(ReplaceTestOverrides)
.Build();
ServiceProvider = host.Services;
}
public IServiceProvider ServiceProvider { get; }
private void ReplaceTestOverrides(IServiceCollection services)
{
// services.Replace(new ServiceDescriptor(typeof(ServiceToReplace), testImplementation));
}
private class TestStartup : Startup
{
public override void Configure(IFunctionsHostBuilder builder)
{
SetExecutionContextOptions(builder);
base.Configure(builder);
}
private static void SetExecutionContextOptions(IFunctionsHostBuilder builder)
{
builder.Services.Configure<ExecutionContextOptions>(o => o.AppDirectory = Directory.GetCurrentDirectory());
}
}
}
TestCollection.cs
[CollectionDefinition(Name)]
public class TestCollection : ICollectionFixture<TestHost>
{
public const string Name = nameof(TestCollection);
}
HttpRequestFactory.cs: To create Http Post Request
public static class HttpRequestFactory
{
public static DefaultHttpRequest Create(string method, string contentType, Stream body)
{
var request = new DefaultHttpRequest(new DefaultHttpContext());
var contentTypeWithBoundary = new MediaTypeHeaderValue(contentType)
{
Boundary = $"----------------------------{DateTime.Now.Ticks.ToString("x")}"
};
var boundary = MultipartRequestHelper.GetBoundary(
contentTypeWithBoundary, (int)body.Length);
request.Method = method;
request.Headers.Add("Cache-Control", "no-cache");
request.Headers.Add("Content-Type", contentType);
request.ContentType = $"{contentType}; boundary={boundary}";
request.ContentLength = body.Length;
request.Body = body;
return request;
}
private static string GetBoundary(MediaTypeHeaderValue contentType, int lengthLimit)
{
var boundary = HeaderUtilities.RemoveQuotes(contentType.Boundary);
if (string.IsNullOrWhiteSpace(boundary.Value))
{
throw new InvalidDataException("Missing content-type boundary.");
}
if (boundary.Length > lengthLimit)
{
throw new InvalidDataException(
$"Multipart boundary length limit {lengthLimit} exceeded.");
}
return boundary.Value;
}
}
The MultipartRequestHelper.cs class is available here
And Finally the Test class:
[Collection(TestCollection.Name)]
public class UploadImagesTests
{
readonly UploadImages UploadImagesFunction;
public UploadImagesTests(TestHost testHost)
{
UploadImagesFunction = new UploadImages(testHost.ServiceProvider.GetRequiredService<IBlobService>());
}
[Theory]
[InlineData("testfile2.jpg")]
public async void HttpTrigger_ShouldReturnListOfUploadedUris(string fileNames)
{
var formFile = GetFormFile(fileNames);
var fileStream = formFile.OpenReadStream();
var request = HttpRequestFactory.Create("POST", "multipart/form-data", fileStream);
var response = (OkObjectResult)await UploadImagesFunction.Run(request);
//fileStream.Close();
Assert.True(response.StatusCode == StatusCodes.Status200OK);
}
private static IFormFile GetFormFile(string fileName)
{
string fileExtension = fileName.Substring(fileName.IndexOf('.') + 1);
string fileNameandPath = GetFilePathWithName(fileName);
IFormFile formFile;
var stream = File.OpenRead(fileNameandPath);
switch (fileExtension)
{
case "jpg":
formFile = new FormFile(stream, 0, stream.Length,
fileName.Substring(0, fileName.IndexOf('.')),
fileName)
{
Headers = new HeaderDictionary(),
ContentType = "image/jpeg"
};
break;
case "png":
formFile = new FormFile(stream, 0, stream.Length,
fileName.Substring(0, fileName.IndexOf('.')),
fileName)
{
Headers = new HeaderDictionary(),
ContentType = "image/png"
};
break;
case "pdf":
formFile = new FormFile(stream, 0, stream.Length,
fileName.Substring(0, fileName.IndexOf('.')),
fileName)
{
Headers = new HeaderDictionary(),
ContentType = "application/pdf"
};
break;
default:
formFile = null;
break;
}
return formFile;
}
private static string GetFilePathWithName(string filename)
{
var outputFolder = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
return $"{outputFolder.Substring(0, outputFolder.IndexOf("bin"))}testfiles\\{filename}";
}
}
The test seems to be hitting the function and req.ContentLength does have a value. Considering this, could it have something to do with the way the File Streams are being managed? Perhaps not the right way?
Any inputs on this would be greatly appreciated.
Thanks
UPDATE 1
As per this post, I have also tried setting the ValueLengthLimit and MultipartBodyLengthLimit in the Startup of the Azure Function and/or the Test Project as opposed to attributes on the Azure Function. The exception then changed to:
"The inner stream position has changed unexpectedly"
Following this, I then set the fileStream position in the test project to SeekOrigin.Begin. I started getting the same error:
"Multipart body length limit 16384 exceeded."
It took me a 50km bike ride and a good nights sleep but I finally figured this one out :-).
The Azure function (AF) accepts an HttpRequest object as a parameter with the name of 'req' i.e.
public async Task Run(
[HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = "images")] HttpRequest req)
The hierarchy of the files object in the HttpRequest object (along with the parameter names) is as follows:
HttpRequest -> req
FormCollection -> Form
FormFileCollection -> Files
This is what the AF accepts and one would access the files collection by using req.Form.Files
In my test case, instead of posting a FormCollection object, I was trying to post a Stream of a file to the Azure Function.
var formFile = GetFormFile(fileNames);
var fileStream = formFile.OpenReadStream();
var request = HttpRequestFactory.Create("POST", "multipart/form-data", fileStream);
As a result of this, req.Form had a Stream value that it could not interpret and the req.Form.Files was raising an exception.
In order to rectify this, I had to do the following:
Revert all changes made as part of UPDATE 1. This means that I removed the 'RequestFormLimits' settings from the Startup file and left them as attributes on the functions Run method.
Instantiate a FormFileCollection object and add the IFormFile to it
Instantiate a FormCollection object using this FormFileCollection as a parameter.
Add the FormCollection to the request object.
To achieve the above, I had to make the following changes in code.
Change 'Create' method in the HttpRequestFactory
public static DefaultHttpRequest Create(string method, string contentType, FormCollection formCollection)
{
var request = new DefaultHttpRequest(new DefaultHttpContext());
var boundary = $"----------------------------{DateTime.Now.Ticks.ToString("x")}";
request.Method = method;
request.Headers.Add("Cache-Control", "no-cache");
request.Headers.Add("Content-Type", contentType);
request.ContentType = $"{contentType}; boundary={boundary}";
request.Form = formCollection;
return request;
}
Add a private static GetFormFiles() method
I wrote an additional GetFormFiles() method that calls the existing GetFormFile() method, instantiate a FormFileCollection object and add the IFormFile to it. This method in turn returns a FormFileCollection.
private static FormFileCollection GetFormFiles(string fileNames)
{
var formFileCollection = new FormFileCollection();
foreach (var file in fileNames.Split(','))
{
formFileCollection.Add(GetFormFile(file));
}
return formFileCollection;
}
Change the Testmethod
The test method calls the GetFormFiles() to get a FormFileCollection then
instantiates a FormCollection object using this FormFileCollection as a parameter and then passes the FormCollection object as a parameter to the HttpRequest object instead of passing a Stream.
[Theory]
[InlineData("testfile2.jpg")]
public async void HttpTrigger_ShouldReturnListOfUploadedUris(string fileNames)
{
var formFiles = GetFormFiles(fileNames);
var formCollection = new FormCollection(null, formFiles);
var request = HttpRequestFactory.Create("POST", "multipart/form-data", formCollection);
var response = (OkObjectResult) await UploadImagesFunction.Run(request);
Assert.True(response.StatusCode == StatusCodes.Status200OK);
}
So in the end the issue was not really with the 'RequestFormLimits' but rather with the type of data I was submitting in the POST message.
I hope this answer provides a different perspective to someone that comes across the same error message.
Cheers.

Application Insights with multiple applications

I have an Application Insights which logs traces from an App Service and an App Function (one resource for 2 functions).
I need to filter traces according to the resource (App Service or App Function) and, if possible, for the App Function which function is actually logging.
Looking at the traces I see the following list of properties:
I thought to find the resource name in the appName property, instead there is the Application Insights resource name, which is useless for me, since all those traces are from that resource.
Note: I don't like the workaround to set a prefix in the message to filter the traces.
UPDATE
I followed Peter Bons suggestions and I created a brand new Function V3 project. The basic version of the project worked also without the Telemetry Initializer, I mean that the Cloud_RoleName property was correctly populated.
Then, I added my changes to adapt the sample code and I found that the problem comes up when I inject a new Telemetry Client. I know, it is not recommended to manually inject TelemetryClient in App Function, but I absolutely need to send Custom Event to Application Insights and, as far as I know, it is not possible with ILogger interface used by default in App Function.
Startup.cs
public class Startup : FunctionsStartup
{
private TelemetryConfiguration telemetryConfiguration;
public override void Configure(IFunctionsHostBuilder builder)
{
var localRoot = Environment.GetEnvironmentVariable("AzureWebJobsScriptRoot");
var azureRoot = $"{Environment.GetEnvironmentVariable("HOME")}/site/wwwroot";
var configBuilder = new ConfigurationBuilder()
.SetBasePath(localRoot ?? azureRoot)
.AddEnvironmentVariables()
.AddJsonFile("local.settings.json", optional: true, reloadOnChange: true);
var configuration = configBuilder.Build();
if (builder != null)
{
this.ConfigureServices(builder.Services, configuration);
}
}
private void ConfigureServices(IServiceCollection services, IConfiguration configuration)
{
services.AddSingleton<ITelemetryInitializer>(x => new CustomTelemetryInitializer(configuration["appFunctionName"]));
telemetryConfiguration = new TelemetryConfiguration(configuration["APPINSIGHTS_INSTRUMENTATIONKEY"]);
telemetryConfiguration.TelemetryInitializers.Add(new OperationCorrelationTelemetryInitializer());
var telemetryClient = new TelemetryClient(telemetryConfiguration);
services.AddSingleton(telemetryClient);
services.AddSingleton<ISampleInterface, SampleService>();
}
}
CustomTelemetryInitializer.cs
public class CustomTelemetryInitializer : ITelemetryInitializer
{
private readonly string roleName;
public CustomTelemetryInitializer(string roleName)
{
this.roleName = roleName;
}
public void Initialize(ITelemetry telemetry)
{
if (string.IsNullOrEmpty(telemetry?.Context?.Cloud?.RoleName))
{
telemetry.Context.Cloud.RoleName = roleName;
}
}
}
SampleService.cs
public class SampleService : ISampleInterface
{
private TelemetryClient telemetryClient;
public SampleService(TelemetryClient telemetryClient)
{
this.telemetryClient = telemetryClient;
}
public void TestAppInsights()
{
telemetryClient.TrackEvent("Sample Custom Event with init");
telemetryClient.TrackTrace("Sample Custom Trace with init");
}
}
Function.cs
public class Function1
{
private ISampleInterface service;
public Function1(ISampleInterface service)
{
this.service = service;
}
[FunctionName("Function1")]
public async Task<IActionResult> Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequest req,
ILogger log)
{
log.LogInformation("C# HTTP trigger function processed a request with init.");
this.service.TestAppInsights();
string name = req.Query["name"];
string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
dynamic data = JsonConvert.DeserializeObject(requestBody);
name = name ?? data?.name;
string responseMessage = string.IsNullOrEmpty(name)
? "This HTTP triggered function executed successfully. Pass a name in the query string or in the request body for a personalized response."
: $"Hello, {name}. This HTTP triggered function executed successfully.";
return new OkObjectResult(responseMessage);
}
}
How about inspecting the cloud_RoleName property, available to all telemetry? By default it will have the name of the webapp or function (including slot names) as the value.
Otherwise, if you want to add custom properties or modify properties for all telemetry at one place you can make use of a telemetry initializer as demonstrated here:
using Microsoft.ApplicationInsights.Channel;
using Microsoft.ApplicationInsights.Extensibility;
namespace CustomInitializer.Telemetry
{
public class MyTelemetryInitializer : ITelemetryInitializer
{
public void Initialize(ITelemetry telemetry)
{
telemetry.Context.Cloud.RoleName = "HttpTriggered";
}
}
}
This avoids having to prefix all traces as you mentioned as a work around by having a single piece of code all telemetry passes through:
Another thing
[...] but I absolutely need to send Custom Event to Application Insights and, as far as I know, it is not possible with ILogger interface used by default in App Function.
Do note that you can redirect the output emitted by using the ILogger interface to Application Insights. It will show up as a trace.

Azure functions integration testing locally

I am trying to run integration tests on an azure functions project locally. My method is to start the azure server programatically using a process. This does not work for some reason.
This is how i setup the process:
private Process process;
private RestClient client;
[OneTimeSetUp]
public void OneTimeSetUp()
{
const string dotnetExePath = #"C:\Program Files\dotnet\dotnet.exe";
const string functionHostPath = #"C:\Users\MyName\AppData\Local\AzureFunctionsTools\Releases\2.24.0\cli\func.dll";
const string functionAppFolder = #"C:\Users\MyName\Source\Repos\ShyftApi\ShyftApi\bin\Debug\netstandard2.0";
process = new Process
{
StartInfo =
{
FileName = dotnetExePath,
Arguments = $"\"{functionHostPath}\" start -p {7001}",
WorkingDirectory = functionAppFolder
}
};
bool success = process.Start();
Assert.AreEqual(true, success);
client = new RestClient($"http://localhost:{7001}/api");
Thread.Sleep(8000);
}
OneTimeSetup succeeds without an error so i assume that the process started correctly (but i see no azure shell, wierd?)
I run a simple http call (using restsharp):
[Test]
public void SimpleTest()
{
RestRequest request = new RestRequest("/test", Method.POST);
IRestResponse response = client.Execute(request);
Assert.AreEqual(200, response.StatusCode);
}
This is the azure function that i am trying to test:
[FunctionName("test")]
public static IActionResult Test([HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = null)]HttpRequest req, TraceWriter log)
{
return new OkObjectResult("ok");
}
The test fails because response.StatusCode is 0 so i assume that the server is not up.
I followed the format used in https://blog.kloud.com.au/2018/11/08/integration-testing-precompiled-v2-azure-functions/ for the arguments to the process. I have manually checked that the paths are correct (But the process starts sucessfully so i dont think the paths are the issue?).
The endpoint i am trying to hit is http://localhost:7071/api/test and when running the azure server regurarly (F5) and accessing it through my browser i get a 200 ok.
What do you think could be the issue? The starting arguments to the process or am i just using the wrong url?
I got it to work now:
private Process process;
private RestClient client;
[OneTimeSetUp]
public void OneTimeSetUp()
{
//Path to azure cli:
const string functionHostPath = #"C:\Users\MyName\AppData\Local\AzureFunctionsTools\Releases\2.24.0\cli\func.exe";
//Path to project build location:
const string functionAppFolder = #"C:\Users\MyName\Source\Repos\ShyftApi\ShyftApi\bin\Debug\netstandard2.0";
int port = 7001;
process = new Process
{
StartInfo =
{
FileName = functionHostPath,
Arguments = $"start -p {port}",
WorkingDirectory = functionAppFolder
}
};
bool success = process.Start();
Assert.AreEqual(true, success);
client = new RestClient($"http://localhost:{port}/api");
Thread.Sleep(5000); //Wait for server to initialize
}
[OneTimeTearDown]
public void OneTimeTearDown()
{
process.CloseMainWindow();
process.Dispose();
}
[Test]
public void SimpleTest()
{
RestRequest request = new RestRequest("test", Method.GET);
IRestResponse response = client.Execute(request);
Assert.AreEqual(HttpStatusCode.OK, response.StatusCode);
}

Unable to use multiple instances of MobileServiceClient concurrently

I structured my project into multiple mobile services, grouped by the application type eg:
my-core.azure-mobile.net (user, device)
my-app-A.azure-mobile.net (sales, order, invoice)
my-app-B.azure-mobile.net (inventory & parts)
I'm using custom authentication for all my services, and I implemented my own SSO by setting the same master key to all 3 services.
Things went well when I tested using REST client, eg. user who "logged in" via custom api at my-core.azure-mobile.net is able to use the returned JWT token to access restricted API of the other mobile services.
However, in my xamarin project, only the first (note, in sequence of creation) MobileServiceClient object is working properly (eg. returning results from given table). The client object are created using their own url and key respectively, and stored in a dictionary.
If i created client object for app-A then only create for app-B, I will be able to perform CRUD+Sync on sales/order/invoice entity, while CRUD+Sync operation on inventory/part entity will just hang there. The situation is inverse if I swap the client object creation order.
I wonder if there is any internal static variables used within the MobileServiceClient which caused such behavior, or it is a valid bug ?
=== code snippet ===
public class AzureService
{
IDictionary<String, MobileServiceClient> services = new Dictionary<String, MobileServiceClient>();
public MobileServiceClient Init (String key, String applicationURL, String applicationKey)
{
return services[key] = new MobileServiceClient (applicationURL, applicationKey);
}
public MobileServiceClient Get(String key)
{
return services [key];
}
public void InitSyncContext(MobileServiceSQLiteStore offlineStore)
{
// Uses the default conflict handler, which fails on conflict
// To use a different conflict handler, pass a parameter to InitializeAsync.
// For more details, see http://go.microsoft.com/fwlink/?LinkId=521416
var syncHandler = new MobileServiceSyncHandler ();
foreach(var client in services) {
client.Value.SyncContext.InitializeAsync (offlineStore, syncHandler);
}
}
public void SetAuthenticationToken(String uid, String token)
{
var user = new MobileServiceUser(uid);
foreach(var client in services) {
client.Value.CurrentUser = user;
client.Value.CurrentUser.MobileServiceAuthenticationToken = token;
}
}
public void ClearAuthenticationToken()
{
foreach(var client in services) {
client.Value.CurrentUser = null;
}
}
}
=== more code ===
public class DatabaseService
{
public static MobileServiceSQLiteStore LocalStore = null;
public static string Path { get; set; }
public static ISet<IEntityMappingProvider> Providers = new HashSet<IEntityMappingProvider> ();
public static void Init (String dbPath)
{
LocalStore = new MobileServiceSQLiteStore(dbPath);
foreach(var provider in Providers) {
var types = provider.GetSupportedTypes ();
foreach(var t in types) {
JObject item = null;
// omitted detail to create JObject using reflection on given type
LocalStore.DefineTable(tableName, item);
}
}
}
}
=== still code ===
public class AzureDataSyncService<T> : IAzureDataSyncService<T>
{
public MobileServiceClient ServiceClient { get; set; }
public virtual Task<List<T>> GetAll()
{
try
{
var theTable = ServiceClient.GetSyncTable<T>();
return theTable.ToListAsync();
}
catch (MobileServiceInvalidOperationException msioe)
{
Debug.WriteLine("GetAll<{0}> EXCEPTION TYPE: {1}, EXCEPTION:{2}", typeof(T).ToString(), msioe.GetType().ToString(), msioe.ToString());
}
catch (Exception e)
{
Debug.WriteLine("GetAll<{0}> EXCEPTION TYPE: {1}, EXCEPTION:{2}", typeof(T).ToString(), e.GetType().ToString(), e.ToString());
}
List<T> theCollection = Enumerable.Empty<T>().ToList();
return Task.FromResult(theCollection);
}
}
=== code ===
public class UserService : AzureDataSyncService<User>
{
}
public class PartService : AzureDataSyncService<Part>
{
}
const string coreApiURL = #"https://my-core.azure-mobile.net/";
const string coreApiKey = #"XXXXX";
const string invApiURL = #"https://my-inventory.azure-mobile.net/";
const string invApiKey = #"YYYYY";
public async void Foo ()
{
DatabaseService.Providers.Add (new CoreDataMapper());
DatabaseService.Providers.Add (new InvDataMapper ());
DatabaseService.Init (DatabaseService.Path);
var coreSvc = AzureService.Instance.Init ("Core", coreApiURL, coreApiKey);
var invSvc = AzureService.Instance.Init ("Inv", invApiURL, invApiKey);
AzureService.Instance.InitSyncContext (DatabaseService.LocalStore);
AzureService.Instance.SetAuthenticationToken("AAA", "BBB");
UserService.Instance.ServiceClient = coreSvc;
PartService.Instance.ServiceClient = invSvc;
var x = await UserService.GetAll(); // this will work
var y = await PartService.GetAll(); // but not this
}
It's ok to use multiple MobileServiceClient objects, but not with the same local database. The offline sync feature uses a particular system tables to keep track of table operations and errors, and it is not supported to use the same local store across multiple sync contexts.
I'm not totally sure why it is hanging in your test, but it's possible that there is a lock on the local database file and the other sync context is waiting to get access.
You should instead use different local database files for each service and doing push and pull on each sync context. With your particular example, you just need to move LocalStore out of DatabaseService and into a dictionary in AzureService.
In general, it seems like an unusual design to use multiple services from the same client app. Is there a particular reason that the services need to be separated from each other?

Render an MVC3 action to a string from a WCF REST service method

I have a WCF REST service that takes some parameters and sends an email. The template for the email is an MVC3 action. Essentially I want to render that action to a string.
If it were an ASP.NET WebForm, I could simply use Server.Execute(path, stringWriter, false). However when I plug in the path to my action, I get Error executing child request.
I have full access to HttpContext from my service (AspNetCompatibilityRequirementsMode.Allowed).
I know there are other answers out there for rendering actions to strings from within the context of a controller. How do I do this when I'm outside that world, but still on the same server (and, for that matter, in the same app)?
I cobbled together an answer based on several different google searches. It works, but I'm not 100% sure it's as lean as it could be. I'll paste the code for others to try.
string GetEmailText(TemplateParameters parameters) {
// Get the HttpContext
HttpContextBase httpContextBase =
new HttpContextWrapper(HttpContext.Current);
// Build the route data
var routeData = new RouteData();
routeData.Values.Add("controller", "EmailTemplate");
routeData.Values.Add("action", "Create");
// Create the controller context
var controllerContext = new ControllerContext(
new RequestContext(httpContextBase, routeData),
new EmailTemplateController());
var body = ((EmailTemplateController)controllerContext.Controller)
.Create(parameters).Capture(controllerContext);
return body;
}
// Using code from here:
// http://blog.approache.com/2010/11/render-any-aspnet-mvc-actionresult-to.html
public class ResponseCapture : IDisposable
{
private readonly HttpResponseBase response;
private readonly TextWriter originalWriter;
private StringWriter localWriter;
public ResponseCapture(HttpResponseBase response)
{
this.response = response;
originalWriter = response.Output;
localWriter = new StringWriter();
response.Output = localWriter;
}
public override string ToString()
{
localWriter.Flush();
return localWriter.ToString();
}
public void Dispose()
{
if (localWriter != null)
{
localWriter.Dispose();
localWriter = null;
response.Output = originalWriter;
}
}
}
public static class ActionResultExtensions
{
public static string Capture(this ActionResult result, ControllerContext controllerContext)
{
using (var it = new ResponseCapture(controllerContext.RequestContext.HttpContext.Response))
{
result.ExecuteResult(controllerContext);
return it.ToString();
}
}
}

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