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URL: https://www.cdata.com/kb/tech/presto-ado-mvc.rst

⇱ Build MVC Applications with Connectivity to Presto Data

Build MVC Applications with Connectivity to Presto Data

👁 Jerod Johnson
Jerod Johnson
Director, Technology Evangelism
This article shows how to use only the Entity Framework and the CData ADO.NET provider to access Presto from an ASP.NET MVC application.

In this article, we will guide you through the process of utilizing wizards within Visual Studio to seamlessly integrate the CData ADO.NET Provider for Presto into a basic MVC (Model, View, Controller) project.

About Presto Data Integration

Accessing and integrating live data from Trino and Presto SQL engines has never been easier with CData. Customers rely on CData connectivity to:

  • Access data from Trino v345 and above (formerly PrestoSQL) and Presto v0.242 and above (formerly PrestoDB)
  • Read and write access all of the data underlying your Trino or Presto instances
  • Optimized query generation for maximum throughput.

Presto and Trino allow users to access a variety of underlying data sources through a single endpoint. When paired with CData connectivity, users get pure, SQL-92 access to their instances, allowing them to integrate business data with a data warehouse or easily access live data directly from their preferred tools, like Power BI and Tableau.

In many cases, CData's live connectivity surpasses the native import functionality available in tools. One customer was unable to effectively use Power BI due to the size of the datasets needed for reporting. When the company implemented the CData Power BI Connector for Presto they were able to generate reports in real-time using the DirectQuery connection mode.


Getting Started


Create the Entity Framework Model

Follow the steps below to save connection properties and map tables to entities in the data model.

  1. Create a new MVC project in Visual Studio. In this example, the project name is MvcPrestoApp.

  2. If you are using Entity Framework 6, you will need to take the preliminary step of registering the Presto Entity Framework provider for your project. See the "LINQ and Entity Framework" chapter in the help documentation for a guide.

    Note that MVC 3 scaffolding and MVC 4 scaffolding do not support Entity Framework 6. You can use your scaffolding with Entity Framework 6 by upgrading to the latest version of MVC.
  3. To add the .edmx file from the designer, right-click your Models folder and click Add New Item. Select ADO.NET Entity Data Model, name the model, and click Add. In this example, the name of the model is PrestoModel.
  4. In the Entity Data Model wizard, select the option 'EF Designer from database'. The Entity Data Model wizard is displayed.
  5. Click New Connection. Select CData Presto Data Source in the dialog that is displayed.

  6. Specify the required connection string properties.

    Set the Server and Port connection properties to connect, in addition to any authentication properties that may be required.

    To enable TLS/SSL, set UseSSL to true.

    Authenticating with LDAP

    In order to authenticate with LDAP, set the following connection properties:

    • AuthScheme: Set this to LDAP.
    • User: The username being authenticated with in LDAP.
    • Password: The password associated with the User you are authenticating against LDAP with.

    Authenticating with Kerberos

    In order to authenticate with KERBEROS, set the following connection properties:

    • AuthScheme: Set this to KERBEROS.
    • KerberosKDC: The Kerberos Key Distribution Center (KDC) service used to authenticate the user.
    • KerberosRealm: The Kerberos Realm used to authenticate the user with.
    • KerberosSPN: The Service Principal Name for the Kerberos Domain Controller.
    • KerberosKeytabFile: The Keytab file containing your pairs of Kerberos principals and encrypted keys.
    • User: The user who is authenticating to Kerberos.
    • Password: The password used to authenticate to Kerberos.

    A typical connection string is below:

    Server=127.0.0.1;Port=8080;
    👁 The connection for the model. (QuickBooks is shown.)

  7. Name the connection and select whether to include sensitive information, such as connection credentials, in the connection string. For simplicity, this example saves sensitive information in Web.config. The connection settings are saved as PrestoEntities.

    👁 The completed connection step in the ADO.NET Entity Data Model wizard. (A QuickBooks connection is shown.)
  8. Select the tables and views you need. In this example, Customer is imported. Also, the option to pluralize object names is deselected in this example. Click Finish to create the .edmx file.👁 Tables to be imported into the .edmx file. (QuickBooks is shown.)
  9. Build your project to complete this step.

Scaffold the Controller and Views

Once you've established the model and completed the project build, you can employ ASP.NET Scaffolding wizards to generate both the controller and the views.

  1. In Solution Explorer, right-click the controllers folder and click Add -> Controller. Select MVC 5 Controller with views, using Entity Framework.
  2. In the Add Controller dialog that is then displayed, select the following options:
    • Model class: Select a table you imported; for example, Customer.
    • Data context class: Select your context class.
  3. Leave the default values for the other fields. 👁 Creating a new controller from an existing entity data model in the Add Controller dialog in MVC 5. (QuickBooks is shown.)
You can now access the list of Customer records at http://MySite/Customer. Next to each record are links to edit, delete, and see more information. You can also create new Customer records. With every state change the site picks up any data changes. 👁 The live table. (QuickBooks is shown.)