UM4RS

User Modeling framework For Recommender Systems UM4RS (pronounced UMARS) is an open-source C# .NetFramework-based modeling framework. This is library will store and manage the User and Context and Activity information needed for a Context-Aware Recommender Systems (CARS). The model also support the information about the Items the CARS will recommend.

---

Features

• C# using EntityFramework Code First as ORM strategy
• Well structured Object-Oriented architecture
• Scientific investigation project
• Developer-friendly, by developers, to developers "developers, developers, developers...."

Usage

    // specify the connection string
    UM4RS.ModelORM.ConString = @"Data Source=.\SQLEXPRESS;Initial Catalog=UM4RS;Integrated Security=True";

    // create a db Connection
    using (var db = new ModelORM())
    {
        // create objects
        var user = new User();
        user.Contact = new Contact();
        user.Contact.FirstName = "John";
        user.Contact.LastName = "Doe";

        // or using object initializers
        var address = new Address()
        {
           Street = "One Microsoft Way",
           City = "Redmond",
           State = "Washington"
        };
        user.Contact.Address = address;

        // save the data (saving  the root object will save children)
        db.Users.Add(user);
        db.SaveChanges();
    }    

Read the documentation

See the list of classes

Or explore the framework interactively using VisualStudio Intellisence

Retrieving data

Data retrieval can be done through the static method of the model classes. The following example shows:

1. how to get the list of all records (users in this case).
2. how to get a record by its id
3. how to get the records that match a given query.

    var userList = User.GetAll(); 
    var theUser = User.Get(42);   
    var singleUser = User.FindAll(x => x.Contact.FirstName == "John");

Installation and Configuration

• Include UM4RS.dll and Linq2CSV.dll in your project References

• Include a Reference to EntityFramework: Manual: Reference the provided EntityFramework.dll Nuget: Install-Package EntityFramework

• Include a Reference for EntityFramework database provider:

  • For SQL Server: EntityFramework.SqlServer Manual: Reference the provided EntityFramework.SqlServer.dll Nuget: Install-Package EntityFramework.SqlServer

  • For MySql database server: Nuget: Install-Package MySql.Data.Entity.EF6 More info: Mysql page

Connection String

• Configure the ConnectionString to allow the model communicate with a database. Ensure the connection string is configure before any database involved action.

    UM4RS.ModelORM.ConString = "my connection string here";   
    // example: @"Data Source=.\SQLEXPRESS;Initial Catalog=UM4RS;Integrated Security=True";

For more details of how to create/configure a connection string visit HERE

Entity IDs

All Entity subclasses will have an ID, that represent the KEY column of the Database. By Detault the ID is Autoincrementable and has a private set. If you want to assign your own values to the ID, annotate the property in the desired class with:

    [DatabaseGenerated(DatabaseGeneratedOption.None)]

NOTES: When the ID is non autogenerated, is you retrieve objects with Class.Get(id), the retrieved instance has no tracking enabled, therefore when you modify it, and want to save it again it will try to create a new record with a duplicated ID and an EntityFramework exception will raise, in other words (language) that is:

    var usr = new User()
    {
        Id = 1
    };
    usr.Save(); 
    // until here no problem, you assigned your own ID to the Entity

    usr.Demographic = new Demographic()
    {
        Gender = Gender.Female
    };
    usr.Save(); // <- Exception raise here
    // EF tried to create a new (User) record with the same Id

If you need (really want) to assign the ID values, we recommend working with creating/updating entities this way:

    using (var db = new ModelORM())
    {
        var usr = new User() {Id = 1};
        db.Users.Add(usr);
        db.SaveChanges();

        usr.Demographic = new Demographic()
        {
            Gender = Gender.Male
        };
        db.SaveChanges();
    }