Set public properties in ServiceStack web services - servicestack

I am trying to write unit tests for ServiceStack services using Sqlite. Since Sqlite doesn't support stored procedures, I've created public property of type 'ServiceCommand' that takes command text and command type as inputs. By default it is configured to run stored procedure and while writing unit test cases, I am re-assigning the SelectCommand property to sql query against sqlite before calling Any() method as below. All test cases work fine.
var request = new CustomerRequest() { name = "alfki" };
var service = new CustomerService(InMemoryTestDatabase.OpenDbConnection());
service.SelectCommand = new ServiceCommand() { SQL = "SELECT * FROM customers where customerid = {0}" };
var result = service.Any(request);
But per this thread, public properties of CustomerService are set to null by IOC while resolving the references thus SelectCommand is null in Any() method resulting in object reference error. By setting the property as protected, private, internal or static, I will not be able to run unit tests.
public class CustomerService : Service
{
private readonly IDbConnection _dbConnection;
public ServiceCommand SelectCommand {get;set;}
public CustomerService(IDBConnection dbConnection)
{
_dbConnection = dbConnection; //injected successfully
SelectCommand = new ServiceCommand(){ SQL = "sp_getcustomers",
CommandType = CommandType.StoredProcedure};
}
public Customer Any(CustomerRequest request)
{
//Select command is not accessible here.
}
}
[Route("/customers")]
public class CustomerRequest
{
public string name { get; set; }
}
ServiceCommand
public class ServiceCommand
{
public string SQL { get; set; }
public CommandType CommandType { get; set; }
public ServiceCommand()
{
CommandType = CommandType.Text;
}
}
To be able to run test cases and service as well, I've modified Any() method to instantiate ServiceCommand if it is null. I would like to know if this is the way to go or any better alternatives.
public class CustomerService : Service
{
private readonly IDbConnection _dbConnection; // injected successfully
public ServiceCommand SelectCommand {get;set;}
public CustomerService(IDBConnection dbConnection)
{
_dbConnection = dbConnection; //injected successfully
}
public Customer Any(CustomerRequest request)
{
SelectCommand = SelectCommand ?? new ServiceCommand() { SQL = "sp_getCustomers",CommandType = CommandType.StoredProcedure };
}
}

Since ServiceStack services will inject registered IOC properties for all public properties it will override the value you set in the constructor so you can't make it a public property without registering it in the IOC since it will be overridden to null.
Given this, some possible options are:
Make it a public field
public class CustomerService : Service
{
public ServiceCommand SelectCommand = new ServiceCommand {
SQL = "sp_getcustomers",
CommandType = CommandType.StoredProcedure };
...
}
Inject a read-only property with a setter
service.SetSelectCommand(
new ServiceCommand { SQL = "SELECT * FROM customers where customerid = {0}" });
Register it in your IOC and specify it in your constructor
container.Register(new ServiceCommand {
SQL = "sp_getcustomers",
CommandType = CommandType.StoredProcedure });
and change constructor to:
public CustomerService(IDBConnection dbConnection, ServiceCommand serviceCommand)
{
_dbConnection = dbConnection;
_serviceCommand = serviceCommand;
}

Related

How to use DI in this example?

I followed this example https://learn.microsoft.com/pt-br/azure/app-service/webjobs-sdk-get-started and it is working fine. What I want to do is to make the connection strings (strongly typed) available in all methods within Functions class. My Connection Strings object:
namespace MyApp.Domain
{
public class Secrets
{
public class ConnectionStrings
{
public string SqlServer {get; set;}
public string Storage {get; set;}
public string SendGrid {get; set;}
public string AzureWebJobsDashboard { get; set; }
public string AzureWebJobsStorage {get; set;}
}
}
}
In web project I use (and it works perfectly):
services.Configure<Secrets.ConnectionStrings>(Configuration.GetSection("CUSTOMCONNSTR_ConnectionStrings"));
and in the classes' constructors I use:
public class EmailController: ControllerBase
{
private readonly MyEmail _myEmail;
public EmailController(MyEmail MyEmail)
{
_myEmail = MyEmail;
}
[HttpGet]
public async Task<ActionResult<string>> SendEmail()
{
try
{
...
return await _myEmail.SendMailMI3D(myMsg);
}
catch (System.Exception ex)
{
return ex.Message + " - " + ex.StackTrace;
}
}
[HttpGet("sendgrid")]
public string GetSendGrid(long id)
{
return _myEmail.SendGridConnStr();
}
}
But this way doesn't work on webjobs (console apps).
I tried to insert a simple Console.WriteLine in Functions' constructor but it doesn't work as well. So I think this is the problem: Functions' constructor is not being called. So when I insert a message in my queue I receive this error message related to DI Connection String:
Microsoft.Azure.WebJobs.Host.FunctionInvocationException: Exception while executing function: Functions.ProcessQueueMessage ---> System.NullReferenceException: Object reference not set to an instance of an object.
Can anybody please help me? Thanks a lot.
public Functions(IOptions<Secrets.ConnectionStrings> ConnectionStrings)
{
_connectionStrings = ConnectionStrings;
Console.WriteLine("Simple line");
Console.WriteLine($"Functions constructor: ${_connectionStrings.Value.SendGrid}");
}
Microsoft.Azure.WebJobs.Host.FunctionInvocationException: Exception while executing function: Functions.ProcessQueueMessage ---> System.NullReferenceException: Object reference not set to an instance of an object.
Dependency Injection is available in WebJobs but you do need to take the extra step to create an IJobActivator to define the injection.
namespace NetCoreWebJob.WebJob
{
public class JobActivator : IJobActivator
{
private readonly IServiceProvider services;
public JobActivator(IServiceProvider services)
{
this.services = services;
}
public T CreateInstance<T>()
{
return services.GetService<T>();
}
}
}
Inside Main()
var config = new JobHostConfiguration();
config.JobActivator = new JobActivator(services.BuildServiceProvider());
That should allow the runtime to utilize the parameterized constructor.

Error when adding Where or OrderBy clauses to Azure Mobile Apps request

I'm developing an Azure Mobile App service to interface to my Xamarin application.
I've created, connected and successfully populated an SQL Database, but when I try to add some filters to my request, for example an orderby() or where() clauses, it returns me a Bad Request error.
For example, this request: https://myapp.azurewebsites.net/tables/Race?$orderby=iRound%20desc,iYear%20desc&$top=1&ZUMO-API-VERSION=2.0.0 gives me {"message":"The query specified in the URI is not valid. Could not find a property named 'IYear' on type 'MyType'."}.
My configuration method is this:
HttpConfiguration config = new HttpConfiguration();
new MobileAppConfiguration()
.AddTablesWithEntityFramework()
.ApplyTo(config);
config.MapHttpAttributeRoutes();
Database.SetInitializer(new CreateDatabaseIfNotExists<MainDataContext>());
app.UseWebApi(config);
and my DbContext is this:
public class MainDataContext : DbContext
{
private const string connectionStringName = "Name=MS_TableConnectionString";
public MainDataContext() : base(connectionStringName)
{
Database.Log = s => WriteLog(s);
}
public void WriteLog(string msg)
{
System.Diagnostics.Debug.WriteLine(msg);
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Add(
new AttributeToColumnAnnotationConvention<TableColumnAttribute, string>(
"ServiceTableColumn", (property, attributes) => attributes.Single().ColumnType.ToString()));
}
public DbSet<Race> Race { get; set; }
public DbSet ...ecc...
}
Following this guide, I added a migration after creating my TableControllers. So the TableController for the example type shown above is pretty standard:
[EnableQuery(AllowedQueryOptions = AllowedQueryOptions.All)]
public class RaceController : TableController<Race>
{
protected override void Initialize(HttpControllerContext controllerContext)
{
base.Initialize(controllerContext);
MainDataContext context = new MainDataContext();
DomainManager = new EntityDomainManager<Race>(context, Request);
}
// GET tables/Race
[EnableQuery(AllowedQueryOptions = AllowedQueryOptions.All)]
public IQueryable<Race> GetAllRace()
{
return Query();
}
// GET tables/Race/48D68C86-6EA6-4C25-AA33-223FC9A27959
public SingleResult<Race> GetRace(string id)
{
return Lookup(id);
}
// PATCH tables/Race/48D68C86-6EA6-4C25-AA33-223FC9A27959
public Task<Race> PatchRace(string id, Delta<Race> patch)
{
return UpdateAsync(id, patch);
}
// POST tables/Race
public async Task<IHttpActionResult> PostRace(Race item)
{
Race current = await InsertAsync(item);
return CreatedAtRoute("Tables", new { id = current.Id }, current);
}
// DELETE tables/Race/48D68C86-6EA6-4C25-AA33-223FC9A27959
public Task DeleteRace(string id)
{
return DeleteAsync(id);
}
}
As you can see, I already tried to add the EnableQuery attribute to my TableController, as seen on Google. I also tried to add these filters to the HttpConfiguration object, without any success:
config.Filters.Add(new EnableQueryAttribute
{
PageSize = 10,
AllowedArithmeticOperators = AllowedArithmeticOperators.All,
AllowedFunctions = AllowedFunctions.All,
AllowedLogicalOperators = AllowedLogicalOperators.All,
AllowedQueryOptions = AllowedQueryOptions.All
});
config.AddODataQueryFilter(new EnableQueryAttribute
{
PageSize = 10,
AllowedArithmeticOperators = AllowedArithmeticOperators.All,
AllowedFunctions = AllowedFunctions.All,
AllowedLogicalOperators = AllowedLogicalOperators.All,
AllowedQueryOptions = AllowedQueryOptions.All
});
I don't know what to investigate more, as things seems to be changing too fast for a newbie like me who's first got into Azure.
EDIT
I forgot to say that asking for the complete table, so for example https://myapp.azurewebsites.net/tables/Race?ZUMO-API-VERSION=2.0.0, returns correctly the entire dataset. The problem occurs only when adding some clauses to the request.
EDIT 2
My model is like this:
public class Race : EntityData
{
public int iRaceId { get; set; }
public int iYear { get; set; }
public int iRound { get; set; }
ecc..
}
and the database table that was automatically created is this, including all the properties inherited from EntityData:
Database table schema
Digging into the source code, Azure Mobile Apps sets up camelCase encoding of all requests and responses. It then puts them back after transmission accordign to rules - so iRaceId becomes IRaceId on the server.
The easiest solution to this is to bypass the auto-naming and use a JsonProperty attribute on each property within your server-side DTO and client-side DTO so that they match and will get encoding/decoded according to your rules.
So:
public class Race : EntityData
{
[JsonProperty("id")]
public string Id { get; set; }
[JsonProperty("raceId")]
public int iRaceId { get; set; }
[JsonProperty("year")]
public int iYear { get; set; }
[JsonProperty("round")]
public int iRound { get; set; }
etc..
}

How to get nested element using ServiceStack?

Although I am able to access the SchemaVersion using code below, I cannot access FormatDocID nested element.
Any ideas how can I easily get FormatDocID using ServiceStack and AutoQueryFeature (or similar)?
I put only relevant parts of code here
public override void Configure(Container container)
{
JsConfig.DateHandler = DateHandler.ISO8601;
SetupValidators(container);
SetupIOC(container);
SetupPlugins(container, log);
ContentTypes.Register("application/xml"
, CLXmlSerializer.Serialize, ServiceStack.Text.XmlSerializer.DeserializeFromStream);
SetupMetaDataRedirectionPath();
SetupGlobalResponseFilters();
}
Setup plugins
private void SetupPlugins(Container container)
{
Plugins.Add(new ValidationFeature());
Plugins.Add(new SwaggerFeature());
Plugins.Add(new AutoQueryFeature
{
MaxLimit = 1000,
EnableUntypedQueries = false,
IncludeTotal = true
});
Plugins.Add(new AutoQueryDataFeature {MaxLimit = 100}
.AddDataSource(ctx => ctx.MemorySource(new List<WordDocument>
{
new WordDocument()
{
SchemaVersion = "",
Format = new Word.DocumentFormat()
{
FormatDocID = 254
}
}
}))
);
typeof(RequestLogs).AddAttributes(new RestrictAttribute {VisibilityTo = RequestAttributes.None});
typeof(AssignRoles).AddAttributes(new RestrictAttribute {VisibilityTo = RequestAttributes.None});
typeof(UnAssignRoles).AddAttributes(new RestrictAttribute {VisibilityTo = RequestAttributes.None});
typeof(Authenticate).AddAttributes(new RestrictAttribute {VisibilityTo = RequestAttributes.None});
}
Serializable classes
public abstract class Document
{
public DocumentFormat Format;
public class DocumentFormat
{
[XmlAttribute] public int Version;
public int FormatDocID;
public string DocShortName;
}
}
public class WordDocument : Document
{
[XmlAttribute] public string SchemaVersion { get; set; } = "1.0";
}
Thanks in advance for the answers.
It's not clear what you're trying to achieve or why, AutoQuery creates Auto Queryable APIs where the Response is the API Response serialized in the specified Response Content Type.
If you want to intercept the Typed Response DTO before it's returned you can create a Custom AutoQuery Implementation and introspect the response that way, e.g:
public class MyQueryServices : Service
{
public IAutoQueryData AutoQuery { get; set; }
//Override with custom implementation
public object Any(MyQuery query)
{
var q = AutoQuery.CreateQuery(query, base.Request);
var response = AutoQuery.Execute(query, q);
return response;
}
}
But the AutoQuery Memory Data Source you're using lets you provide your own collection of Typed POCOs as the Data source so you already have access to them when you create it, but the source POCOs should be a flat Type with public properties (in contrast to your class with public fields and nested types) - it's not possible to query nested object graph values.
This is an example of a POCO that doesn't use nested classes, or public fields:
public abstract class Document
{
public int Version { get; set; }
public int FormatDocID { get; set; }
public string DocShortName { get; set; }
}
So the solution if you want to use AutoQuery would be to change your Data Source to use Flat POCOs with public properties otherwise you'd need to create the impl of your Service yourself.

Abstract Azure IMobileServiceTable<T> behind repository

I want my repsository to be independent of the data access technology. Currently I am working on a Xamrin.Forms App that uses Azure Mobile App Services for data access. For performance and flexibility reasons I want my repository to look simmilar like the following:
Task<IEnumerable<IDomainObject>> GetDomainObjectAsync(Func<IQueryable<IDomainObject>, IQueryable<IDomainObject>> query)
Suppose my IDomainObject looks like the following:
public interface IDomainObject
{
string Name { get; }
}
and my DataAccess Object:
internal class AzureDomainObject : IDomainObject
{
public string Name { get; set; }
public string Id { get; set; }
}
As far as I found out and tested I can do the following to query the database within my repository implementation:
public async Task<IEnumerable<IDomainObject>> GetDomainObjectAsync(Func<IQueryable<IDomainObject>, IQueryable<IDomainObject>> query)
{
// _table of type IMobileServiceTable<AzureDomainObject> gotten by MobileServiceClient
var tableQuery = _table.GetQuery();
tableQuery.Query = tableQuery.Query.Take(4); // 1) this was for testing and it works (ordering etc also works)
// tableQuery.Query = query(tableQuery.Query); // 2) this was my initial idea how to use the input param
await _table.ReadAsync(tableQuery);
}
My poblem now is how to use the input param query to replace 1) with 2).
tableQuery.Query expects an IQueryable<AzureDomainObject> but query is of type IQueryable<IDomainObject>.
Neither .Cast<AzureDomainObject>() nor .OfType<AzureDomainObject>() work to convert. Nor does (IQueryable<IAzureDomainObject>)query; work.
Cast and OfType throw NotSupportedException and the hard cast throws an InvalidCastException.
I also tried to extract the Expression from the query input param and assign it to the tableQuery.Query. But then a runtime exception occurs that they are not compatible.
Another idea I had was to use the ReadAsync(string) overload and pass the string representation of the passed query param. But this way I don't know how to generate the string.
So the final question is: Does anyone knows how to hide both AzureDomainObject and IMobileServiceTable from the domain model but keep the flexibility and performance benefits of IQueryable in the repository interface?
According to your description, I checked this issue and here is my implementation for this scenario, you could refer to them.
Model:
public class TodoItem : IDomainObject
{
public string Id { get; set; }
[JsonProperty(PropertyName = "text")]
public string Text { get; set; }
[JsonProperty(PropertyName = "complete")]
public bool Complete { get; set; }
}
public interface IDomainObject
{
string Id { get; set; }
}
Repository:
public interface IAzureCloudTableRepository<T> where T : IDomainObject
{
Task<IEnumerable<T>> GetDomainObjectAsync(Func<IQueryable<T>, IQueryable<T>> query);
}
public class AzureCloudTableRepository<T> : IAzureCloudTableRepository<T> where T : IDomainObject
{
IMobileServiceTable<T> table;
public AzureCloudTableRepository(MobileServiceClient client)
{
this.table = client.GetTable<T>();
}
public async Task<T> CreateItemAsync(T item)
{
await table.InsertAsync(item);
return item;
}
public async Task<IEnumerable<T>> GetDomainObjectAsync(Func<IQueryable<T>, IQueryable<T>> query)
{
var tableQuery = this.table.CreateQuery();
tableQuery.Query = tableQuery.Query.Take(4); //the internal fixed query
tableQuery.Query = query(tableQuery.Query); //the external query
return await tableQuery.ToEnumerableAsync();
}
}
TEST:
var mobileService = new MobileServiceClient("https://{your-app-name}.azurewebsites.net");
var todoitem = new AzureCloudTableRepository<TodoItem>(mobileService);
var items = await todoitem.GetDomainObjectAsync((query) =>
{
return query.Where(q => q.Text!=null);
});

How do I access a derived class value from a base class static method?

Here is a sample of what I am trying to accomplish:
public class BaseClass<T>
{
public static T GetByID(int ID)
{
// Need database name here that is determined at design time in the derived class.
var databaseName = "";
// do some stuff involving database name that gets me object by ID here.
return default(T);
}
}
public class DerivedClass : BaseClass<DerivedClass>
{
private string DatabaseName { get; set; }
}
Basically, how would I access the derived "DatabaseName" in the base class static GetByID method?
EDIT: After I posted this, I tried one more thing. I played with attributes earlier, and failed, but I think my brain was mushy. Just tried again and ran a test, and it is working. Here is the updated sample.
public class BaseClass<T>
{
public static T GetByID(int ID)
{
// Need database name here that is determined at design time in the derived class.
var databaseName = ((DatabaseAttribute)typeof(T).GetCustomAttributes(typeof(DatabaseAttribute), true).First()).DatabaseName;
// do some stuff involving database name that gets me object by ID here.
return default(T);
}
}
[Database("MyDatabase")]
public class DerivedClass : BaseClass<DerivedClass>
{
}
public class DatabaseAttribute : Attribute
{
public DatabaseAttribute(string databaseName)
{
DatabaseName = databaseName;
}
public string DatabaseName { get; set; }
}
Base class to derived class is a one-way inheritance: The base class has no knowledge of the existance of a derived class, and so it can't access it.
In addition to that you will have a hard time accessing a non-static property from a static method.
I know you've already answered your own question, but some improvements....
Add a where clause to guarantee inheritance, it means any static methods can make use of inherited methods. You might also want to add the new() clause if you wish to be able to create instances of the inherited class.
public class BaseClass<T> : where T : BaseClass<T>
{
static readonly string databaseName;
static BaseClass() {
// Setup database name once per type of T by putting the initialization in
// the static constructor
databaseName = typeof(T).GetCustomAttributes(typeof(DatabaseAttribute),true)
.OfType<DatabaseAttribute>()
.Select(x => x.Name)
.FirstOrDefault();
}
public static T GetByID(int ID)
{
// Database name will be in the static field databaseName, which is unique
// to each type of T
// do some stuff involving database name that gets me object by ID here.
return default(T);
}
}
[Database("MyDatabase")]
public class DerivedClass : BaseClass<DerivedClass>
{
}
public class DatabaseAttribute : Attribute
{
public DatabaseAttribute(string databaseName)
{
DatabaseName = databaseName;
}
public string DatabaseName { get; set; }
}

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