Rystem.RepositoryFramework.Abstractions 1.1.15

What is Rystem?

Interfaces

Based on CQRS we could split our repository pattern in two main interfaces, one for update (write, delete) and one for read.

Command (Write-Delete)

public interface ICommandPattern<T, TKey, TState> : ICommandPattern
    where TKey : notnull
    where TState : class, IState<T>, new()
{
    Task<TState> InsertAsync(TKey key, T value, CancellationToken cancellationToken = default);
    Task<TState> UpdateAsync(TKey key, T value, CancellationToken cancellationToken = default);
    Task<TState> DeleteAsync(TKey key, CancellationToken cancellationToken = default);
    Task<List<BatchResult<TKey, TState>>> BatchAsync(List<BatchOperation<T, TKey>> operations, CancellationToken cancellationToken = default);
}

Query (Read)

public interface IQueryPattern<T, TKey, TState> : IQueryPattern
    where TKey : notnull
    where TState : class, IState<T>, new()
{
    Task<T?> GetAsync(TKey key, CancellationToken cancellationToken = default);
    Task<TState> ExistAsync(TKey key, CancellationToken cancellationToken = default);
    Task<IEnumerable<T>> QueryAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default);
    Task<long> CountAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default);
}

Repository Pattern (Write-Delete-Read)

Repository pattern is a sum of CQRS interfaces.

public interface IRepositoryPattern<T, TKey, TState> : ICommandPattern<T, TKey, TState>, IQueryPattern<T, TKey, TState>, IRepositoryPattern, ICommandPattern, IQueryPattern
    where TKey : notnull
    where TState : class, IState<T>, new()
{
}

With State as TState

Command (Write-Delete)

public interface ICommandPattern<T, TKey> : ICommandPattern<T, TKey, State<T>>, ICommandPattern
    where TKey : notnull
{
    Task<State<T>> InsertAsync(TKey key, T value, CancellationToken cancellationToken = default);
    Task<State<T>> UpdateAsync(TKey key, T value, CancellationToken cancellationToken = default);
    Task<State<T>> DeleteAsync(TKey key, CancellationToken cancellationToken = default);
    Task<List<BatchResult<TKey, State<T>>>> BatchAsync(List<BatchOperation<T, TKey>> operations, CancellationToken cancellationToken = default);
}

Query (Read)

public interface IQueryPattern<T, TKey> : IQueryPattern<T, TKey, State<T>>, IQueryPattern
    where TKey : notnull
{
    Task<T?> GetAsync(TKey key, CancellationToken cancellationToken = default);
    Task<State<T>> ExistAsync(TKey key, CancellationToken cancellationToken = default);
    Task<IEnumerable<T>> QueryAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default);
    Task<long> CountAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default);
}

Repository Pattern (Write-Delete-Read)

Repository pattern is a sum of CQRS interfaces.

public interface IRepositoryPattern<T, TKey> : IRepositoryPattern<T, TKey, State<T>>, ICommandPattern<T, TKey>, IQueryPattern<T, TKey>, IRepositoryPattern, ICommandPattern, IQueryPattern
    where TKey : notnull
{
}

With State as TState and string as TKey

Command (Write-Delete)

public interface ICommandPattern<T> : ICommandPattern<T, string>, ICommandPattern
{
    Task<State<T>> InsertAsync(string key, T value, CancellationToken cancellationToken = default);
    Task<State<T>> UpdateAsync(string key, T value, CancellationToken cancellationToken = default);
    Task<State<T>> DeleteAsync(string key, CancellationToken cancellationToken = default);
    Task<List<BatchResult<string, State<T>>>> BatchAsync(List<BatchOperation<T, string>> operations, CancellationToken cancellationToken = default);
}

Query (Read)

public interface IQueryPattern<T> : IQueryPattern<T, string>, IQueryPattern
{
    Task<T?> GetAsync(string key, CancellationToken cancellationToken = default);
    Task<State<T>> ExistAsync(string key, CancellationToken cancellationToken = default);
    Task<IEnumerable<T>> QueryAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default);
    Task<long> CountAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default);
}

Repository Pattern (Write-Delete-Read)

Repository pattern is a sum of CQRS interfaces.

public interface IRepositoryPattern<T> : IRepositoryPattern<T, string>, ICommandPattern<T>, IQueryPattern<T>, IRepositoryPattern, ICommandPattern, IQueryPattern
    where TKey : notnull
{
}    

Examples

Model

public class User
{
    public string Id { get; set; }
    public string Name { get; set; }
    public string Email { get; set; }
}

Command

public class UserWriter : ICommandPattern<User, string>
{
    public Task<State<T>> DeleteAsync(string key, CancellationToken cancellationToken = default)
    {
        //delete on with DB or storage context
        throw new NotImplementedException();
    }
    public Task<State<T>> InsertAsync(string key, User value, CancellationToken cancellationToken = default)
    {
        //insert on DB or storage context
        throw new NotImplementedException();
    }
    public Task<State<T>> UpdateAsync(string key, User value, CancellationToken cancellationToken = default)
    {
        //update on DB or storage context
        throw new NotImplementedException();
    }
    public Task<List<BatchResult<string, State<T>>>> BatchAsync(List<BatchOperation<User, string>> operations, CancellationToken cancellationToken = default)
    {
        //insert, update or delete some items on DB or storage context
        throw new NotImplementedException();
    }
}

Query

public class UserReader : IQueryPattern<User, string>
{
    public Task<User?> GetAsync(string key, CancellationToken cancellationToken = default)
    {
        //get an item by key from DB or storage context
        throw new NotImplementedException();
    }
    public Task<State<T>> ExistAsync(string key, CancellationToken cancellationToken = default)
    {
        //check if an item by key exists in DB or storage context
        throw new NotImplementedException();
    }
    public Task<IEnumerable<User>> QueryAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default)
    {
        //get a list of items by a predicate with top and skip from DB or storage context
        throw new NotImplementedException();
    }
    public Task<long> CountAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default)
    {
        //get an items count by a predicate with top and skip from DB or storage context
        throw new NotImplementedException();
    }
}

Alltogether as repository pattern

if you don't have CQRS infrastructure (usually it's correct to use CQRS when you have minimum two infrastructures one for write and delete and at least one for read)

public class UserRepository : IRepositoryPattern<User, string>, IQueryPattern<User, string>, ICommandPattern<User, string>
{
    public Task<State<T>> DeleteAsync(string key, CancellationToken cancellationToken = default)
    {
        //delete on with DB or storage context
        throw new NotImplementedException();
    }
    public Task<State<T>> InsertAsync(string key, User value, CancellationToken cancellationToken = default)
    {
        //insert on DB or storage context
        throw new NotImplementedException();
    }
    public Task<State<T>> UpdateAsync(string key, User value, CancellationToken cancellationToken = default)
    {
        //update on DB or storage context
        throw new NotImplementedException();
    }
    public Task<List<BatchResult<string, State<T>>>> BatchAsync(List<BatchOperation<User, string>> operations, CancellationToken cancellationToken = default)
    {
        //insert, update or delete some items on DB or storage context
        throw new NotImplementedException();
    }
    public Task<User?> GetAsync(string key, CancellationToken cancellationToken = default)
    {
        //get an item by key from DB or storage context
        throw new NotImplementedException();
    }
    public Task<State<T>> ExistAsync(string key, CancellationToken cancellationToken = default)
    {
        //check if an item by key exists in DB or storage context
        throw new NotImplementedException();
    }
    public Task<IEnumerable<User>> QueryAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default)
    {
        //get a list of items by a predicate with top and skip from DB or storage context
        throw new NotImplementedException();
    }
    public Task<long> CountAsync(QueryOptions<T>? options = null, CancellationToken cancellationToken = default)
    {
        //get an items count by a predicate with top and skip from DB or storage context
        throw new NotImplementedException();
    }
}

How to use it

In DI you install the service

services.AddRepository<User, string, UserRepository>();

And you may inject the object

IRepository<User, string> repository

Query and Command

In DI you install the services

services.AddCommand<User, string, UserWriter>();
services.AddQuery<User, string, UserReader>();

And you may inject the objects

ICommand<User, string> command
IQuery<User, string> command

Example with default key

In DI you install the services

services.AddRepository<User, UserRepository>();
services.AddCommand<User, UserWriter>();
services.AddQuery<User, UserReader>();

And you may inject the objects

IRepository<User> repository
ICommand<User> command
IQuery<User> command

Example with TState

In DI you install the services, in example we are using a Result class that is an IState<T>, instead the default integration State.

services.AddRepository<User, string, Result, UserRepository>();
services.AddCommand<User, string, Result, UserWriter>();
services.AddQuery<User, string, Result, UserReader>();

And you may inject the objects

IRepository<User, string, Result> repository
ICommand<User, string, Result> command
IQuery<User, string, Result> command

Twice or more configurations for the same repository service

Pay attention during the DI, you may install the same repository two or more times for the same model. If you want to be sure, you may start the DI with a method that checks for you. When can it happen? For instance, when you use at the same time InMemory integration with a custom integration.

services.ThrowExceptionIfARepositoryServiceIsAddedTwoOrMoreTimes();

TKey when it's not a primitive

You can use a class or record. Record is better, for example, if you want to use the Equals operator from key, with record you don't check it by the refence but by the value of the properties in the record. My key:

public class MyKey 
{
    public int Id { get; set; }
    public int Id2 { get; set; }
}

the DI

services.AddRepository<User, MyKey, Result, UserRepository>();

and you may inject (for ICommand and IQuery is the same)

IRepository<User, MyKey, Result> repository

Default TKey record

You may use the default record in repository framework namespace. For 1 value (it's not really useful I know, but I liked to create it).

new Key<int>(2);

or for 2 values

new Key<int, int>(2, 4);

or for 3 values

new Key<int, int, string>(2, 4, "312");

or for 4 values

new Key<int, int, string, Guid>(2, 4, "312", Guid.NewGuid());

or for 5 values

new Key<int, int, string, Guid, string>(2, 4, "312", Guid.NewGuid(), "3232");

the DI

services.AddRepository<User, Key<int, int>, Result, UserRepository>();

and you may inject (for ICommand and IQuery is the same)

IRepository<User, Key<int, int>, Result> repository