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Cannot convert string to TimeSpan

So, i am creating a service (using ASP.NETCore 3.1) that receives information about the operation schedule of a shop that can be registered in the system. For that i have an entity which communicates to the database and a model which communicates with this entity, as follows:
Entity:
public class OperationSchedule
{
public int Id { get; set; }
public TimeSpan Open { get; set; }
public TimeSpan Close { get; set; }
public DayOfWeek DatofWeek { get; set; }
}
Model:
public class OperationScheduleModel
{
public TimeSpan Open { get; set; }
public TimeSpan Close { get; set; }
public DayOfWeek DatofWeek { get; set; }
}
Of course they were already mapped using automapper. I'm using swagger to test such communications. The problem begins when i try to post a new "operation schedule", swagger shows me the following output:
Error converting value "string" to type 'System.TimeSpan'
In my first attemption to resolve this problem i'd tryied to use Microsoft.AspNetCore.Mvc.NewtonsoftJson, and configured it in startup this way: services.AddMvc().AddNewtonsoftJson();
As long it does not resolved my problem i was thinking in map the types string and TimeSpan on Automapper by doing something like this:
public class AutoMapperProfile : Profile
{
public AutoMapperProfile()
{
// Custom types mapping
CreateMap<string, TimeSpan>.ConvertUsing<StringToTimeSpanConverter>();
// OperationSchedule mapping
CreateMap<OperationSchedule, OperationScheduleModel>();
CreateMap<OperationScheduleModel, OperationSchedule>();
}
}
But VisualStudio isn't letting me do so, saying that a cannot use "StringToTimeSpanConverter" as a generic property, something like ConvertUsing(new StringToTimeSpanConverter()); doesn't make any difference.
I really can't even imagine another way to resolve it, but may i missing something? Help please

Error converting value "string" to type 'System.TimeSpan'
The reason for this is that System.Text.Json doesn't support TimeSpan.
One solution is to go back to JSON.NET. Here are the steps:
Add a package reference to Microsoft.AspNetCore.Mvc.NewtonsoftJson.
Update Startup.ConfigureServices to call AddNewtonsoftJson.
services.AddControllers()
.AddNewtonsoftJson();
Another option is to use a custom converter for that TimeSpan:
public class CustomConverter : JsonConverter<TimeSpan>
{
public override TimeSpan Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
{
var value = reader.GetString();
return TimeSpan.Parse(value);
}
public override void Write(Utf8JsonWriter writer, TimeSpan value, JsonSerializerOptions options)
{
writer.WriteStringValue(value.ToString());
}
}
Register it in Startup.ConfigureServices with AddJsonOptions:
services.AddControllers()
.AddJsonOptions(options =>
options.JsonSerializerOptions.Converters.Add(new CustomConverter())
);
Result:

Dynamically change a type with C#

I am very new to C# and ServiceStack and I am working on a small project that consists on calling a third party API and loading the data I get back from the API into a relational database via ServiceStack's ORMLite.
The idea is to have each endpoint of the API have a reusable model that determines how it should be received in the API's response, and how it should be inserted into the database.
So I have something like the following:
[Route("/api/{ApiEndpoint}", "POST")]
public class ApiRequest : IReturn<ApiResponse>
{
public Int32 OrderId { get; set; }
public DateTime PurchaseDate { get; set; }
public String ApiEndpoint { get; set; }
}
public class ApiResponse
{
public Endpoint1[] Data { get; set; }
public String ErrorCode { get; set; }
public Int32 ErrorNumber { get; set; }
public String ErrorDesc { get; set; }
}
public class Endpoint1
{
[AutoIncrement]
public Int32 Id { get; set; }
[CustomField("DATETIME2(7)")]
public String PurchaseDate { get; set; }
[CustomField("NVARCHAR(50)")]
public String Customer { get; set; }
[CustomField("NVARCHAR(20)")]
public String PhoneNumber { get; set; }
public Int32 Amount { get; set; }
}
My first class represents the API's request with its route, the second class represents the API's response. The API's response is the same for all endpoints, but the only thing that varies is the structure of the Data field that comes back from that endpoint. I've defined the structure of one of my endpoints in my Endpoint1 class, and I am using it in my API's response class. As you can see, I am also defining a few attributes on my Endpoint1 class to help the ORM make better decisions later when inserting the data.
Ok, so the issue is that I have about 15 endpoints and I don't want to create 15 ApiResponse classes when I know the only thing that changes is that first Data field in the class.
So I made something like this:
public class DataModels
{
public Type getModel(String endpoint)
{
Dictionary<String, Type> models = new Dictionary<String, Type>();
models.Add("Endpoint1", typeof(Endpoint1));
// models.Add("Endpoint2", typeof(Endpoint2));
// models.Add("Endpoint3", typeof(Endpoint3));
// and so forth...
return models[endpoint];
}
}
I would like for getModel() to be called when the request is made so that I can pass in the ApiEndpoint field in the ApiRequest class and store the type that I want my Data field to have so that I can dynamically change it in my ApiResponse class.
In addition, there is the ORM part where I iterate over every endpoint and create a different table using the model/type of each endpoint. Something like this:
endpoints.ForEach(
(endpoint) =>
{
db.CreateTableIfNotExists<Endpoint1>();
// inserting data, doing other work etc
}
);
But again, I'd like to be able to call getModel() in here and with that define the model of the specific endpoint I am iterating on.
I've attempted calling getModel() on both places but I always get errors back like cannot use variable as a typeand others... so I am definitely doing something wrong.
Feel free to suggest a different approach to getModel(). This is just what I came up with but I might be ignoring a much simpler approach.

When I DID understand you correctly, you have different API-Calls which all return the same object. The only difference is, that the field "Data" can have different types.
Then you can simply change the type of data to object:
public object Data { get; set; }
And later simply cast this to the required object:
var data1=(Endpoint1[]) response.Data;

You're going to have a very tough time trying to dynamically create .NET types dynamically which requires advanced usage of Reflection.Emit. It's self-defeating trying to dynamically create Request DTOs with ServiceStack since the client and metadata services needs the concrete Types to be able to call the Service with a Typed API.
I can't really follow your example but my initial approach would be whether you can use a single Service (i.e. instead of trying to dynamically create multiple of them). Likewise with OrmLite if the Schema of the POCOs is the same, it sounds like you would be able to flatten your DataModel and use a single database table.
AutoQuery is an example of a feature which dynamically creates Service Implementations from just a concrete Request DTO, which is effectively the minimum Type you need.
So whilst it's highly recommended to have explict DTOs for each Service you can use inheritance to reuse the common properties, e.g:
[Route("/api/{ApiEndpoint}/1", "POST")]
public ApiRequest1 : ApiRequestBase<Endpoint1> {}
[Route("/api/{ApiEndpoint}/2", "POST")]
public ApiRequest2 : ApiRequestBase<Endpoint1> {}
public abstract class ApiRequestBase<T> : IReturn<ApiResponse<T>>
{
public int OrderId { get; set; }
public DateTime PurchaseDate { get; set; }
public string ApiEndpoint { get; set; }
}
And your Services can return the same generic Response DTO:
public class ApiResponse<T>
{
public T[] Data { get; set; }
public String ErrorCode { get; set; }
public Int32 ErrorNumber { get; set; }
public String ErrorDesc { get; set; }
}
I can't really understand the purpose of what you're trying to do so the API design is going to need modifications to suit your use-case.
You're going to have similar issues with OrmLite which is a Typed code-first POCO ORM where you're going to run into friction trying to use dynamic types which don't exist at Runtime where you'll likely have an easier time executing Dynamic SQL since it's far easier to generate a string than a .NET Type.
With that said GenericTableExpressions.cs shows an example of changing the Table Name that OrmLite saves a POCO to at runtime:
const string tableName = "Entity1";
using (var db = OpenDbConnection())
{
db.DropAndCreateTable<GenericEntity>(tableName);
db.Insert(tableName, new GenericEntity { Id = 1, ColumnA = "A" });
var rows = db.Select(tableName, db.From<GenericEntity>()
.Where(x => x.ColumnA == "A"));
Assert.That(rows.Count, Is.EqualTo(1));
db.Update(tableName, new GenericEntity { ColumnA = "B" },
where: q => q.ColumnA == "A");
rows = db.Select(tableName, db.From<GenericEntity>()
.Where(x => x.ColumnA == "B"));
Assert.That(rows.Count, Is.EqualTo(1));
}
Which uses these extension methods:
public static class GenericTableExtensions
{
static object ExecWithAlias<T>(string table, Func<object> fn)
{
var modelDef = typeof(T).GetModelMetadata();
lock (modelDef)
{
var hold = modelDef.Alias;
try
{
modelDef.Alias = table;
return fn();
}
finally
{
modelDef.Alias = hold;
}
}
}
public static void DropAndCreateTable<T>(this IDbConnection db, string table)
{
ExecWithAlias<T>(table, () => {
db.DropAndCreateTable<T>();
return null;
});
}
public static long Insert<T>(this IDbConnection db, string table, T obj, bool selectIdentity = false)
{
return (long)ExecWithAlias<T>(table, () => db.Insert(obj, selectIdentity));
}
public static List<T> Select<T>(this IDbConnection db, string table, SqlExpression<T> expression)
{
return (List<T>)ExecWithAlias<T>(table, () => db.Select(expression));
}
public static int Update<T>(this IDbConnection db, string table, T item, Expression<Func<T, bool>> where)
{
return (int)ExecWithAlias<T>(table, () => db.Update(item, where));
}
}
But it's not an approach I'd take personally, if I absolutely needed (and I'm struggling to think of a valid use-case outside of table-based Multitenancy or sharding) to save the same schema in multiple tables I'd just be using inheritance again, e.g:
public class Table1 : TableBase {}
public class Table2 : TableBase {}
public class Table3 : TableBase {}

ASP.NET Swagger IEnumerable<T>

In Swagger UI I get a model like:
Inline Model [
Inline Model 1
]
Inline Model 1 {
Id (string, optional),
ConnectionString (string, optional),
ConnectionState (string, optional)
}
for a REST Get method like:
public IEnumerable<Device> Get()
{
return new List<Device>();
}
Why is it not displayed correctly?
Adding Swagger Config from comments
public class SwaggerConfig
{
public static void Register()
{
var thisAssembly = typeof(SwaggerConfig).Assembly;
GlobalConfiguration.Configuration .EnableSwagger(c => { c.SingleApiVersion("v1", "api"); }) .EnableSwaggerUi(c => { });
}
}
public class Device
{
public string Id { get; set; }
public string ConnectionString { get; set; }
public string ConnectionState { get; set; }
}

In C# Asp.Net web api, I did this:
1- In SwaggerConfig.cs
.EnableSwagger(c =>
{//add this line
c.SchemaFilter<ApplyModelNameFilter>();
}
2- add a class that implements ISchemaFilter:
class ApplyModelNameFilter : ISchemaFilter
{
public void Apply(Schema schema, SchemaRegistry schemaRegistry, Type type)
{
schema.title = type.Name;
}
}
I got the idea from here

It seems like Swagger and/or NSwag do not handle Generic List/IList/IEnumerable types very well as a base type, perhaps because some frameworks that may try to connect with Swagger don't understand them.
I have worked around this by wrapping my List in another object. So, in your case, you may need to do something like:
public ListResponseObject<T>()
{
public IEnumerable<T> ResponseList {get; set;}
}
And then return from your controller like this:
public ListResponseObject<Device> Get()
{
return new ListResponseObject<Device>{ResponseList = new List<Device>()};
}
Not as simple... but should get it through Swagger better.
We've leveraged this to our advantage. We've applied this technique to all controllers (or something similar) so we have a more standardized response. We can also do this:
public ListResponseObject<T>() : ResponseObject<T>
{
public IEnumerable<T> ResponseList {get; set;}
}
public ResponseObject<T>()
{
public string Message {get; set;}
public string Status {get; set;}
}
And now you have a container that will make downstream handling a little easier.
Not an exact answer, but a work-around that's worked for us. YMMV
UPDATE: Here's a response to a question I posted in the NSwag GitHub issues:
I think its correct as is. Currently swagger and json schema do not support generics (only for arrays) and thus all generic types are expanded to non-generic/specific types... altough the models should be correct but you may end up with lots of classes...
An enhancement for supporting generics is planned but this will be not compliant with swagger and only work with nswag... (No support in swagger ui)

serialized property to complex type in dto with linq and automapper

I'm having a hard time figuring something out that seems as a "easy" problem.
I'm working with Microsoft Azure mobile apps .Net backend, a MSSQL database, Entity Framework code-first and AutoMapper.
So i have the following objects:
public class Route
{
public string Id { get; set; }
[...] //some other properties
public string SerializedGoogleRoute { get; set; }
}
public class DtoRoute
{
public string Id { get; set; }
[...]
public DtoGoogleRoute GoogleRoute { get; set; }
}
public class DtoGoogleRoute
{
[...] //only strings, ints,...
}
So what I want to do is: In the database save the GoogleRoute as a serialized string because it consists of many properties and I don't need them in different columns - I just want it as a serialized string in one column on the route entity.
When the Route object is projected to the DtoRoute object I want the GoogleRoute to be serialized and vice versa.
Because I'm working with LINQ / queryables I am limited to a few AutoMapper mapping options (see AutoMapper wiki). And with none of these I can't get it to work.
The problems I'm facing/what I tried:
I can't serialize/deserialize the string to the DtoGoogleRoute on mapping (with MapFrom or ConstructProjectionUsing) because LINQ obviously cannot transform the JsonConvert.Serialize/Deserialize methods to SQL statements.
I tried having a DtoGoogleRoute property in the Route object and a string property in the DtoRoute object with getters/setters doing the (de)serialization. This works almost perfectly in a custom API controller but because of the OData query filter the azure mobile app .Net backend uses in the tablecontrollers again only the serialized string property gets returned to the client (because OData/LINQ does not know of the other property).
Another option was making a complex type out of DtoGoogleRoute with Entity Framework - this works fine but not with AutoMapper because AutoMapper can't handle complex types.
For now I'm working with a custom API controller and this works. But it would be better to use the tablecontrollers because they support offline sync.
I can't imagine such a simple thing (at least I thought it was a simple thing) can't be done or is so hard to do. But maybe the problem is all the components (tablecontroller, OData, LINQ, EF, AutoMapper) involved.
I would really be thankful if someone could help.
[EDIT]: I think the fact that it works with a normal api controller and not with a tablecontroller has something to do with OData. I tried putting the same code in a tablecontroller method and in an API controller method. when calling the API controller method I can see on the server that it just calls this function and returns all the right properties to the client (checked with fiddler). But when calling the tablecontroller method the tablecontroller method "rewrites" the URL to a OData URL --> I think this is because of some of the EnableQuery or other OData attributes. Because here (although not AutoMapper but it seems like a similar project from Microsoft) it says that the EnableQuery attribute is called twice - also when the request leaves the server. And I think it cuts of the GoogleRoute property because it does not know about this property in the OData metadata or something like that.

You can achieve it like this -
internal class RouteToDtoConverter : TypeConverter<Route, DtoRoute>
{
protected override DtoRoute ConvertCore(Route source)
{
return new DtoRoute
{
Id = source.Id,
GoogleRoute = JsonConvert.DeserializeObject<DtoGoogleRoute>(source.SerializedGoogleRoute)
};
}
}
internal class DtoToRouteConverter : TypeConverter<DtoRoute, Route>
{
protected override Route ConvertCore(DtoRoute source)
{
return new Route
{
Id = source.Id,
SerializedGoogleRoute = JsonConvert.SerializeObject(source.GoogleRoute)
};
}
}
public class Route
{
public string Id { get; set; }
public string SerializedGoogleRoute { get; set; }
}
public class DtoRoute
{
public string Id { get; set; }
public DtoGoogleRoute GoogleRoute { get; set; }
}
public class DtoGoogleRoute
{
public int MyProperty { get; set; }
public int MyProperty2 { get; set; }
}
AutoMapper.Mapper.CreateMap<Route, DtoRoute>()
.ConvertUsing(new RouteToDtoConverter());
AutoMapper.Mapper.CreateMap<DtoRoute, Route>()
.ConvertUsing(new DtoToRouteConverter());
var res = Mapper.Map<DtoRoute>(new Route
{
Id = "101",
SerializedGoogleRoute = "{'MyProperty':'90','MyProperty2':'09'}"
});
var org = Mapper.Map<Route>(res); //pass

Automapper profiles not working

Does anyone know why this works:
Mapper.Configuration.RecognizeDestinationPrefixes("Foo");
Mapper.CreateMap<A, B>();
But this doesn't:
Mapper.CreateProfile("FooPrefix").RecognizeDestinationPrefixes("Foo");
Mapper.CreateMap<A, B>()
.WithProfile("FooPrefix");
?

While this question is quite old now, I thought it would be useful to answer it given I spent ages trying to get profiles to work.
Although there are a bunch of ways to configure profiles, it seems that the only way what I could get it to work was as follows:
public class ExampleProfile : Profile
{
protected override void Configure()
{
ReplaceMemberName("Z", "A");
CreateMap<Source, Destination>(); // Notice this is CreateMap, NOT Mapper.CreateMap...
}
public override string ProfileName
{
get { return this.GetType().Name; }
}
}
Then, set up the profile in your config:
Mapper.Initialize(cfg => cfg.AddProfile<ExampleProfile>());
Given the Source and Destination classes as follows:
public class Source
{
public string Zabc { get; set; }
}
public class Destination
{
public string Aabc { get; set; }
}
This should now work:
var source = new Source { Zabc = "source" };
var dest = Mapper.Map<Destination>(source);
Assert.AreEqual(source.Zabc, dest.Aabc);

Profile names are different. You use FooxPrefix when creating the profile and then use FooPrefix when creating the map.