I have a class (many more fields than defined below, but you get the basic idea):
public class Embedded
{
public int Field1{get;set;}
}
public class Source
{
public int Field2{get;set;}
public Embedded Embedded{get;set;}
}
public class Destination
{
public int Field1{get;set;}
public int Field2{get;set;}
}
The normal approach would be:
Mapper.Initialise(cfg=>
{
cfg.CreateMap<Source, Destination>(dest=>dest.Field1, opt=>opt.MapFrom(src=>src.Embedded.Field1));
}
My Embedded object has many fields (and I have multiple embedded objects) and they will map by convention to the fields in the Destination object.
I need something like the functionality provided by IncludeBase<> but to be able to specify which field should be used to use as the src.
Is there a simpler way of doing this?
I found Map<,>(s,d) and AfterMap:
Mapper.Initialize(cfg=>{
cfg.CreateMap<Embedded, Destination>();
cfg.CreateMap<Source, Destination>()
.AfterMap((s,d) {
Mapper.Map(s.Embedded, d);
}
});
var src = new Source{
Embedded = new Embedded();
}
var dest = Mapper.Map<Source, Destination>(src);
Related
I'm using Dapper Extensions and have defined my own custom mapper to deal with entities with composite keys.
public class MyClassMapper<T> : ClassMapper<T> where T : class
{
public MyClassMapper()
{
// Manage unmappable attributes
IList<PropertyInfo> toIgnore = typeof(T).GetProperties().Where(x => !x.CanWrite).ToList();
foreach (PropertyInfo propertyInfo in toIgnore.ToList())
{
Map(propertyInfo).Ignore();
}
// Manage keys
IList<PropertyInfo> propsWithId = typeof(T).GetProperties().Where(x => x.Name.EndsWith("Id") || x.Name.EndsWith("ID")).ToList();
PropertyInfo primaryKey = propsWithId.FirstOrDefault(x => string.Equals(x.Name, $"{nameof(T)}Id", StringComparison.CurrentCultureIgnoreCase));
if (primaryKey != null && primaryKey.PropertyType == typeof(int))
{
Map(primaryKey).Key(KeyType.Identity);
}
else if (propsWithId.Any())
{
foreach (PropertyInfo prop in propsWithId)
{
Map(prop).Key(KeyType.Assigned);
}
}
AutoMap();
}
}
I also have this test case to test my mapper:
[Test]
public void TestMyAutoMapper()
{
DapperExtensions.DapperExtensions.DefaultMapper = typeof(MyClassMapper<>);
MySubscribtionEntityWithCompositeKey entity = new MySubscribtionEntityWithCompositeKey
{
SubscriptionID = 145,
CustomerPackageID = 32
};
using (var connection = new SqlConnection(CONNECTION_STRING))
{
connection.Open();
var result = connection.Insert(entity);
var key1 = result.SubscriptionID;
var key2 = result.CustomerPackageID;
}
}
Note that I set the default mapper in the test case.
The insert fails and I notive that my customer mapper is never called. I have no documentation on the github page on the topic, so I'm not sure if there's anything else I need to do to make dapper extensions use my mapper.
Thanks in advance!
Looking at your question, you are attempting to write your own defalut class mapper derived from the existing one. I never used this approach; so I do not know why it is not working or whether it should work.
I explicitly map the classes as below:
public class Customer
{
public int CustomerID { get; set; }
public string Name { get; set; }
}
public sealed class CustomerMapper : ClassMapper<Customer>
{
public CustomerMapper()
{
Schema("dbo");
Table("Customer");
Map(x => x.CustomerID).Key(KeyType.Identity);
AutoMap();
}
}
The AutoMap() will map rest of the properties based on conventions. Please refer to these two resources for more information about mapping.
Then I call SetMappingAssemblies at the startup of the project as below:
DapperExtensions.DapperExtensions.SetMappingAssemblies(new[] { Assembly.GetExecutingAssembly() });
The GetExecutingAssembly() is used in above code because mapping classes (CustomerMapper and other) are in same assembly which is executing. If those classes are placed in other assembly, provide that assembly instead.
And that's it, it works.
To set the dialect, I call following line just below the SetMappingAssemblies:
DapperExtensions.DapperExtensions.SqlDialect = new DapperExtensions.Sql.SqlServerDialect();
Use your preferred dialect instead of SqlServerDialect.
Apparently, the solution mentioned here may help you achieve what you are actually trying to. But, I cannot be sure, as I said above, I never used it.
I have 2 classes, Class1 should be mapped to Class2. I do mapping with AutoMapper. I'd like to test my configuration of the mapper and for this purposes I'm using AutoFixture. Source class Class1 has property of type IList<>, destination class Class2 has a similar property but of type IEnumerable<>. To simplify test preparation I'm using AutoFixture (with AutoMoqCustomization) to initialize both source and destination objects. But after initializing property of type IEnumerable<> with AutoFixture, AutoMapper can't map the property.
Error text:
Error mapping types.
Mapping types: Class1 -> Class2 ConsoleApplication1.Class1 ->
ConsoleApplication1.Class2
Type Map configuration: Class1 -> Class2 ConsoleApplication1.Class1 ->
ConsoleApplication1.Class2
Property: Items
Could anybody help me to configure either AutoMapper or AutoFixture to make the mapping work? As a workaround I can assign null to the destination property, but I do not want to do this in the each test.
Simplified example of code:
public class AutoMapperTests
{
public static void TestCollectionsProperty()
{
Mapper.Initialize(cfg =>
{
cfg.CreateMap<ItemClass1, ItemClass2>();
cfg.CreateMap<Class1, Class2>();
});
var src = new Class1();
src.Items = new List<ItemClass1>()
{
new ItemClass1() { Text = "111" },
new ItemClass1() { Text = "222" }
};
var fixture = new Fixture();
var dst = fixture.Create<Class2>();
Mapper.Map(src, dst); //Error at this line of code
}
}
public class Class1
{
public IList<ItemClass1> Items { get; set; }
}
public class Class2
{
public IEnumerable<ItemClass2> Items { get; set; }
}
public class ItemClass1
{
public string Text { get; set; }
}
public class ItemClass2
{
public string Text { get; set; }
}
It's not really an AutoFixture issue per se. You can reproduce it without AutoFixture by instead creating dst like this:
var dst = new Class2();
dst.Items = Enumerable.Range(0, 1).Select(_ => new ItemClass2());
This will produce a similar error message:
Unable to cast object of type 'WhereSelectEnumerableIterator2[System.Int32,Ploeh.StackOverflow.Q45437098.ItemClass2]' to type 'System.Collections.Generic.IList1[Ploeh.StackOverflow.Q45437098.ItemClass2]'
That ought to be fairly self-explanatory: WhereSelectEnumerableIterator<int, ItemClass2> doesn't implement IList<ItemClass2>. AutoMapper attempts to make that cast, and fails.
The simplest fix is probably to avoid populating dst:
var dst = new Class2();
If you must use AutoFixture for this, you can do it like this:
var dst = fixture.Build<Class2>().OmitAutoProperties().Create();
Unless the Class2 constructor does something complex, however, I don't see the point of using AutoFixture in that scenario.
If, on the other hand, you do need dst to be populated, you just need to ensure that dst.Items is convertible to IList<ItemClass2>. One way to do that would be like this:
var dst = fixture.Create<Class2>();
dst.Items = dst.Items.ToList();
You could create a Customization to make sure that this happens automatically, but if you need help with that, please ask a new question (if you don't find one that already answers that question).
Here is a working example for your problem. As #Mark Seemann already told, Mapper.CreateMap has been deprecated, so this example is using the new structure.
Mapper.Initialize(cfg =>
{
cfg.CreateMap<ItemClass1, ItemClass2>();
cfg.CreateMap<Class1, Class2>();
});
var src = new Class1();
src.Items = new List<ItemClass1>()
{
new ItemClass1() { Text = "111" },
new ItemClass1() { Text = "222" }
};
var dest = Mapper.Map<Class1, Class2>(src);
AM requires IList because you're mapping to an existing list and that works by calling IList.Add.
I have few classes and they have multiple list items like below:
public class Request1
{
public List<AdditionalApplicantData> AdditionalApplicantData { get; set;}
public List<ApplicantData> ApplicantData { get; set; }
}
public class Request2
{
public List<ApplicantDetails> ApplicantData { get; set; }
}
I want to map Request1 to Request2 but List of ApplicantData has to be mapped from multiple sources like List of ApplicantData & List of AdditionalApplicantData but not sure how to achieve it can someone please help me here?
You can use function below with createMap() function. Source: https://github.com/AutoMapper/AutoMapper/wiki/Before-and-after-map-actions
.AfterMap((src, dest) => {
dest.ApplicantData = /*your logic here*/
});
And you should mark ApplicantData as don't map because you have a variable named ApplicantData at the source class. You should implement the logic yourself.
EDIT:
When you are initializing mapper, you create map for each object. So for your case it would be like:
Mapper.Initialize(cfg => {
cfg.CreateMap<Request1, Request2>()
.ForMember(x => x.ApplicantData, opt => opt.Ignore()) //You want to implement your logic so ignore mapping
.AfterMap((src, dest) =>
{
dest.ApplicantData = /*implement your logic here*/
});
});
public class ApplicantDetailsResolver : IValueResolver<Request1, Request2, List<ApplicantDetails>>
{
public List<ApplicantDetails> Resolve(Request1 source, Request2 destination,List<ApplicantDetails> destMember, ResolutionContext context)
{
destination.ApplicantDetails = context.Mapper.Map<List<ApplicantDetails>>(source.ApplicantData);
for (int i = 0; i < destination.ApplicantDetails.Count(); i++)
{
context.Mapper.Map(source.AdditionalApplicantData.ElementAt(i), destination.ApplicantDetails.ElementAt(i));
}
return destination.ApplicantDetails;
}
}
I have written above custom value resolver for mapping list from multiple sources and its working fine but problem, is it can't match properties which are differently named, is there way I can handle this scenario as well?
The application I'm working on has several places where we use AutoMapper to map entities.
The problem is if I had a model entity from one side to the other of the project, many times I forget to add the mapping for the new entity (I just need a copy paste from other entities), ending up that the solution compiles and I get no exception.
It just launches the application without full functionality and no debugging messages, which makes difficult to figure out what I've missed.
Is there any way to force the compiler at compile time to give me an error in case I forget to do a mapping?
AFAIK, there isn't a possibility to force compile-time checking for Automapper.
Nevertheless, there is a possibility to verify the correctness of your mappings:
After you've defined all your mappings, call the AssertConfigurationIsValid method which will throws an AutoMapperConfigurationException exception if the defined mappings are broken.
You can make this a part of your unit or integration test suite.
I had the same problem and decided to solve it by wrapping up AutoMapper. For each source-destination map I provide a method that I create after I've added it to my AutoMapper profile.
This may take away some of the ease of implementing AutoMapper but I find the compile time checking worth it.
public class MyType {
public string SomeProperty { get;set; }
}
public class MyOtherType {
public string SomeProperty { get;set; }
}
public class MyAlternateType {
public string AlternateProperty {get;set;}
}
public class AutoMapperProfile : Profile {
public AutoMapperProfile() {
CreateMap<MyType, MyOtherType>();
CreateMap<MyAlternateType, MyOtherType>()
.ForMember(ot => ot.SomeProperty, options => options.MapFrom(at => at.AlternateProperty));
}
}
public interface IMyMappingProvider {
// Uncomment below for Queryable Extensions
//IQueryable<TDestination> ProjectTo<TSource, TDestination>(IQueryable<TSource> source, params Expression<Func<TDestination, object>>[] membersToExpand);
//IQueryable<TDestination> ProjectTo<TSource, TDestination>(IQueryable<TSource> source, IDictionary<string, object> parameters, params string[] membersToExpand);
/*
* Add your mapping declarations below
*/
MyOtherType MapToMyOtherType(MyType source);
MyOtherType MapToMyOtherType(MyAlternateType source);
}
public class MyMappingProvider : IMyMappingProvider {
private IMapper Mapper { get; set; }
public MyMappingProvider(IMapper mapper) {
Mapper = mapper;
}
/* Uncomment this for Queryable Extensions
public IQueryable<TDestination> ProjectTo<TSource, TDestination>(IQueryable<TSource> source, params Expression<Func<TDestination, object>>[] membersToExpand) {
return new ProjectionExpression(source, Mapper.ConfigurationProvider.ExpressionBuilder).To<TDestination>(null, membersToExpand);
}
public IQueryable<TDestination> ProjectTo<TSource, TDestination>(IQueryable<TSource> source, IDictionary<string, object> parameters, params string[] membersToExpand) {
return new ProjectionExpression(source, Mapper.ConfigurationProvider.ExpressionBuilder).To<TDestination>(parameters, membersToExpand);
}
*/
/*
* Implement your mapping methods below
*/
public MyOtherType MapToMyOtherType(MyType source) {
return Mapper.Map<MyType, MyOtherType>(source);
}
public MyOtherType MapToMyOtherType(MyAlternateType source) {
return Mapper.Map<MyAlternateType, MyOtherType>(source);
}
}
If you are using the AutoMapper's Queryable extensions you can add the following class and uncomment the Queryable Extensions code above.
public static class QueryableExtensions {
/*
* Implement your extension methods below
*/
public static IQueryable<MyOtherType> ProjectToMyOtherType(this IQueryable<MyType> source, IMyMappingProvider mapper, params Expression<Func<MyOtherType, object>>[] membersToExpand)
{
return mapper.ProjectTo<MyType, MyOtherType>(source, membersToExpand);
}
public static IQueryable<MyOtherType> ProjectToMyOtherType(this IQueryable<MyAlternateType> source, IMyMappingProvider mapper, params Expression<Func<MyOtherType, object>>[] membersToExpand)
{
return mapper.ProjectTo<MyAlternateType, MyOtherType>(source, membersToExpand);
}
}
Tested with AutoMapper 6.1.1 using LinqPad:
var autoMapperConfig = new MapperConfiguration(cfg => { cfg.AddProfile(new AutoMapperProfile()); });
IMyMappingProvider mapper = new MyMappingProvider(autoMapperConfig.CreateMapper());
var myTypes = new List<MyType>()
{
new MyType() {SomeProperty = "Test1"},
new MyType() {SomeProperty = "Test2"},
new MyType() {SomeProperty = "Test3"}
};
myTypes.AsQueryable().ProjectToMyOtherType(mapper).Dump();
var myAlternateTypes = new List<MyAlternateType>()
{
new MyAlternateType() {AlternateProperty = "AlternateTest1"},
new MyAlternateType() {AlternateProperty = "AlternateTest2"},
new MyAlternateType() {AlternateProperty = "AlternateTest3"}
};
myAlternateTypes.AsQueryable().ProjectToMyOtherType(mapper).Dump();
mapper.MapToMyOtherType(myTypes[0]).Dump();
As #serge.karalenka said, don't forget to still test your mapping configuration by calling AssertConfigurationIsValid().
I am creating a rule set engine that looks kinda like a unit test framework.
[RuleSet(ContextA)]
public class RuleSet1
{
[Rule(TargetingA)]
public Conclusion Rule1(SubjectA subject)
{ Create conclusion }
[Rule(TargetingA)]
public Conclusion Rule2(SubjectA subject)
{ Create conclusion }
[Rule(TargetingB)]
public Conclusion Rule3(SubjectB subject)
{ Create conclusion }
}
[RuleSet(ContextB)]
public class RuleSet2
{
[Rule(TargetingB)]
public Conclusion Rule1(SubjectB subject)
{ Create conclusion }
[Rule(TargetingA)]
public Conclusion Rule2(SubjectA subject)
{ Create conclusion }
[Rule(TargetingB)]
public Conclusion Rule3(SubjectB subject)
{ Create conclusion }
}
public class Conclusion()
{
// Errorcode, Description and such
}
// contexts and targeting info are enums.
The goal is to create an extensible ruleset that doesn't alter the API from consumer POV while having good separation-of-concerns within the code files. Again: like a unit test framework.
I am trying to create a library of these that expose the following API
public static class RuleEngine
{
public static IEnumerable<IRuleSet> RuleSets(contextFlags contexts)
{
{
return from type in Assembly.GetExecutingAssembly().GetTypes()
let attribute =
type.GetCustomAttributes(typeof (RuleSetAttribute), true)
.OfType<RuleSetAttribute>()
.FirstOrDefault()
where attribute != null
select ?? I don't know how to convert the individual methods to Func's.
}
}
}
internal interface IRuleset
{
IEnumerable<Func<SubjectA, Conclusion>> SubjectARules { get; }
IEnumerable<Func<SubjectB, Conclusion>> SubjectBRules { get; }
}
...which allows consumers to simply use like this (using foreach instead of LINQ for readability in this example)
foreach (var ruleset in RuleEgine.RuleSets(context))
{
foreach (var rule in ruleset.SubjectARules)
{
var conclusion = rule(myContextA);
//handle the conclusion
}
}
Also, it would be very helpful if you could tell me how to get rid of "TargetingA" and "TargetingB" as RuleAttribute parameters and instead use reflection to inspect the parameter type of the decorated method directly. All the while maintaining the same simple external API.
You can use Delegate.CreateDelegate and the GetParameters method to do what you want.
public class RuleSet : IRuleSet
{
public IEnumerable<Func<SubjectA, Conclusion>> SubjectARules { get; set; }
public IEnumerable<Func<SubjectB, Conclusion>> SubjectBRules { get; set; }
}
public static class RuleEngine
{
public static IEnumerable<IRuleSet> RuleSets() // removed contexts parameter for brevity
{
var result = from t in Assembly.GetExecutingAssembly().GetTypes()
where t.GetCustomAttributes(typeof(RuleSetAttribute), true).Any()
let m = t.GetMethods().Where(m => m.GetCustomAttributes(typeof(RuleAttribute)).Any()).ToArray()
select new RuleSet
{
SubjectARules = CreateFuncs<SubjectA>(m).ToList(),
SubjectBRules = CreateFuncs<SubjectB>(m).ToList()
};
return result;
}
}
// no error checking for brevity
// TODO: use better variable names
public static IEnumerable<Func<T, Conclusion>> CreateFuncs<T>(MethodInfo[] m)
{
return from x in m
where x.GetParameters()[0].ParameterType == typeof(T)
select (Func<T, Conclusion>)Delegate.CreateDelegate(typeof(Func<T, Conclusion>), null, x);
}
Then you can use it like this:
var sa = new SubjectA();
foreach (var ruleset in RuleEngine.RuleSets())
{
foreach (var rule in ruleset.SubjectARules)
{
var conclusion = rule(sa);
// do something with conclusion
}
}
In your LINQ query you headed straight for RuleSetAttribute, and so lost other information. If you break the query in several lines of code you can get methods from the type with GetMethods(), and then you can call GetCustomAttribute<RuleAttribute>().