Subsonic 3, how to CRUD using LinqTemplates? - subsonic

I am new to Subsonic, and it seems that I cant find out a natural way to do CRUD operations using the LINQ template classes. I guess in ActiveRecord, you could:
Product p = new Product();
p.ProductCode = "xxx";
p.Add();
Using the LINQTemplate generated classes however, how can I do the same thing? I can only use something like this below to insert a product object:
db.Insert.Into<UnleashedSaaS.PRODUCT>(prod => prod.Code, prod => prod.Description).Values("Product1", "Product1 Desc").Execute();
Who could kindly give me some hints? I'd really appreciate it.

All the CRUD happens in SubSonicRepository, which you can derive from. For example, I would have a class like this:
public class ProductRepository : SubSonicRepository<Product> {
public ProductRepository() : base(new NorthwindDB()) { }
// need this here because base doesn't expose the DB class that I know of
protected NorthwindDB _db;
protected NorthwindDB DB {
get {
if (_db == null) _db = new NorthwindDB();
return _db;
}
}
public void Save(Product product) {
if (product.ProductId == 0) {
Add(product); // Add is part of SubSonicRepository
} else {
Update(product);
}
}
public void Delete(Product product) { ... }
public List<Product> ListAll() {
var products = from p in DB.Products
select p;
return products.ToList();
}
public Product GetById(int id) {
return DB.GetByKey(id);
}
}
And so on. It's nice because you can consolidate all your data access methods in one place. If you have Sprocs, they're generated as methods on DB as well.
When I get time I'm going to work on adding a Save method to SubSonicRepository directly so you don't have to do the check yourself to see which method (Add or Update) to call.

I have modified the Classes.tt file to include:
public partial class <#=tbl.ClassName#>Repository : SubSonicRepository<<#=tbl.ClassName#>>
{
public <#=tbl.ClassName#>Repository() : base(new <#=DatabaseName#>DB()) { }
}
Insert that bunch of lines between
<# foreach(Table tbl in tables){#>
and
/// <summary>
right at the top, near the namespace declaration, in my file it can be inserted in line 18.
The last thing to do is to add another "using" statement, in line 10, the next line after System.Linq statement. Now it should look like:
using System.Linq;
using SubSonic.Repository;
That will generate a repository to give you access to basic functionality, but can be modified in another partial class.
Hope that helps.

Related

Dapper Extensions custom ClassMapper isn't called on Insert()

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.

Entity Framework database first approach using stored procedure

I am creating a project that uses Entity framework Database first approach. The .edmx is currently generated and is in my data access layer project.
I have created a function import call GetAllTeam and corresponding complex type call TeamResult. I am trying to return the data to business layer by calling my function import, populating the complex type in the data access layer.
In my business layer I shall then map the complex type to business object and return to my web api. I would like to know if my approach is correct. Do I need to create a separate class project called entities with a class called team and then AutoMap that class with TeamResult the complex type and then return to the business layer or is it fine directly sending the TeamResult to the business layer.
Let me also know if there is any other issue with this approach.
Please see the code below
Data access layer:
public class TeamRepository
{
public IEnumerable<TeamResult> GetAllTeam()
{
using (var mcrContext = new MCREntities1())
{
return (from team in mcrContext.GetAllTeam()
select new TeamResult
{
TeamName = team.TeamName,
TeamDescription = team.TeamDescription,
Code = team.Code
}).ToList();
}
}
}
Business logic layer:
public class TeamService : ITeamService
{
private readonly ITeamRepository _teamRepository;
public TeamService(ITeamRepository teamRepository)
{
_teamRepository = teamRepository;
}
public IEnumerable<TeamDto> GetTeam()
{
IEnumerable<TeamResult> team = _teamRepository.GetAllTeam();
if (team != null)
{
foreach (var t in team)
{
yield return Mapper.Map<TeamDto>(t);
}
}
yield break;
}
}
public class DomainToDtoMapping : Profile
{
public DomainToDtoMapping()
{
CreateMap<TeamResult, TeamDto>().ReverseMap();
}
public override string ProfileName
{
get { return "DomainToDtoMapping"; }
}
}
Web Api:
public class TeamController : ApiController
{
private readonly ITeamService _teamServices;
public TeamController(ITeamService _teamServices)
{
_teamServices = teamServices;
}
public HttpResponseMessage Get()
{
var teams = _teamServices.GetTeam();
if (teams != null)
{
var teamEntities = teams as List<TeamDto> ?? teams.ToList();
if (teamEntities.Any())
return Request.CreateResponse(HttpStatusCode.OK, teamEntities);
}
return Request.CreateErrorResponse(HttpStatusCode.NotFound, "Team not found");
}
}
Personally, I think you are doing this just fine. Having another entity to map the stored procedure to before returning it from the repository wouldn't add any value because you are returning exactly what the stored procedure exposes already.
The business layer needs to know about any entities that the Repository can return and then map it to something to return later. This all looks good to me! :)

How do I create Enumerable<Func<>> out of method instances

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>().

Add behavior to existing implementation - C# / Design Pattern

My current implementation for service and business layer is straight forward as below.
public class MyEntity { }
// Business layer
public interface IBusiness { IList<MyEntity> GetEntities(); }
public class MyBusinessOne : IBusiness
{
public IList<MyEntity> GetEntities()
{
return new List<MyEntity>();
}
}
//factory
public static class Factory
{
public static T Create<T>() where T : class
{
return new MyBusinessOne() as T; // returns instance based on T
}
}
//Service layer
public class MyService
{
public IList<MyEntity> GetEntities()
{
return Factory.Create<IBusiness>().GetEntities();
}
}
We needed some changes in current implementation. Reason being data grew over the time and service & client cannot handle the volume of data. we needed to implement pagination to the current service. We also expect some more features (like return fault when data is more that threshold, apply filters etc), so the design needs to be updated.
Following is my new proposal.
public interface IBusiness
{
IList<MyEntity> GetEntities();
}
public interface IBehavior
{
IEnumerable<T> Apply<T>(IEnumerable<T> data);
}
public abstract class MyBusiness
{
protected List<IBehavior> Behaviors = new List<IBehavior>();
public void AddBehavior(IBehavior behavior)
{
Behaviors.Add(behavior);
}
}
public class PaginationBehavior : IBehavior
{
public int PageSize = 10;
public int PageNumber = 2;
public IEnumerable<T> Apply<T>(IEnumerable<T> data)
{
//apply behavior here
return data
.Skip(PageNumber * PageSize)
.Take(PageSize);
}
}
public class MyEntity { }
public class MyBusinessOne : MyBusiness, IBusiness
{
public IList<MyEntity> GetEntities()
{
IEnumerable<MyEntity> result = new List<MyEntity>();
this.Behaviors.ForEach(rs =>
{
result = rs.Apply<MyEntity>(result);
});
return result.ToList();
}
}
public static class Factory
{
public static T Create<T>(List<IBehavior> behaviors) where T : class
{
// returns instance based on T
var instance = new MyBusinessOne();
behaviors.ForEach(rs => instance.AddBehavior(rs));
return instance as T;
}
}
public class MyService
{
public IList<MyEntity> GetEntities(int currentPage)
{
List<IBehavior> behaviors = new List<IBehavior>() {
new PaginationBehavior() { PageNumber = currentPage, }
};
return Factory.Create<IBusiness>(behaviors).GetEntities();
}
}
Experts please suggest me if my implementation is correct or I am over killing it. If it correct what design pattern it is - Decorator or Visitor.
Also my service returns JSON string. How can I use this behavior collections to serialize only selected properties rather than entire entity. List of properties comes from user as request. (Kind of column picker)
Looks like I don't have enough points to comment on your question. So, I am gonna make some assumption as I am not a C# expert.
Assumption 1: Looks like you are getting the data first and then applying the pagination using behavior object. If so, this is a wrong approach. Lets say there are 500 records and you are showing 50 records per fetch. Instead of simply fetching 50 records from DB, you are fetching 500 records for 10 times and on top of it you are adding a costly filter. DB is better equipped to do this job that C# or Java.
I would not consider pagination as a behavior with respect to the service. Its the behavior of the presentation layer. Your service should only worry about 'Data Granularity'. Looks like one of your customer wants all the data in one go and others might want a subset of that data.
Option 1: In DAO layer, have two methods: one for pagination and other for regular fetch. Based on the incoming params decide which method to call.
Option 2: Create two methods at service level. One for a small subset of data and the other for the whole set of data. Since you said JSON, this should be Restful service. Then based on the incoming URL, properly call the correct method. If you use Jersey, this should be easy.
In a service, new behaviors can be added by simply exposing new methods or adding new params to existing methods/functionalities (just make sure those changes are backward compatible). We really don't need Decorator or Visitor pattern. The only concern is no existing user should be affected.

Create content error - Specified cast is not valid

I have a custom module. Migrations.cs looks like this.
public int Create()
{
SchemaBuilder.CreateTable("MyModuleRecord", table => table
.ContentPartRecord()
...
);
ContentDefinitionManager.AlterPartDefinition(
typeof(MyModulePart).Name, cfg => cfg.Attachable());
ContentDefinitionManager.AlterTypeDefinition("MyModule",
cfg => cfg
.WithPart("MyModulePart")
.WithPart("CommonPart")
.Creatable()
);
return 1;
}
This is the code I have in the controller.
var newcontent = _orchardServices.ContentManager.New<MyModulePart>("MyModule");
...
_orchardServices.ContentManager.Create(newcontent);
I get the invalid cast error from this New method in Orchard.ContentManagement ContentCreateExtensions.
public static T New<T>(this IContentManager manager, string contentType) where T : class, IContent {
var contentItem = manager.New(contentType);
if (contentItem == null)
return null;
var part = contentItem.Get<T>();
if (part == null)
throw new InvalidCastException();
return part;
}
Any idea what I am doing wrong?
Thanks.
This is the handler.
public class MyModuleHandler : ContentHandler
{
public MyModuleHandler(IRepository<MyModuleRecord> repository)
{
Filters.Add(StorageFilter.For(repository));
}
}
You are getting the InvalidCastException because the content item doesn't appear to have your MyModulePart attached.
If there were a driver for your part, then there is an implicit link somewhere that allows your part to be shown on a content item (I'm not sure how this is done, maybe someone else could elaborate - but it is something to do with how shapes are harvested and picked up by the shape table deep down in Orchard's core).
However since you don't have a driver, adding an ActivatingFilter to your part's handler class will make the link explicitly:
public MyModulePartHandler : ContentHandler {
public MyModulePartHandler() {
Filters.Add(StorageFilter.For(repository));
Filters.Add(new ActivatingFilter<MyModulePart>("MyModule");
}
}
Your part table name is wrong. Try renaming it to this (so the part before "Record" matches your part model name exactly):
SchemaBuilder.CreateTable("MyModulePartRecord", table => table
.ContentPartRecord()
...
);

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