Accessing always encrypted column on azure function using reference methods

Question

We have azure functions running on .net core 3.1 and we have methods on a seperate project running on .net framework 4.7.2 and we are trying to use the method in the .net framework 4.7.2 called from the azure function to access a database with encrypted columns using Always Encrypted. When trying to create new instance of Microsoft.Data.SqlClient.SqlConnection we are getting an exception :

System.TypeInitializationException: 'The type initializer for 'Microsoft.Data.SqlClient.SqlConnection' threw an exception.' "MissingMethodException: Method not found: 'System.Security.CodeAccessPermission System.Data.Common.DbProviderFactory.CreatePermission(System.Security.Permissions.PermissionState)'.

The connection string contains "Column Encryption Setting=enabled"

Example of Method in .net framework 4.7.2 ProjectA

public static string MethodA()
{
    string ssn = "";
    try
    {
        string sql = @" SELECT TOP 1 SSN FROM DBO.TESTAETABLE";
        List<SqlParameter> parameters = new List<SqlParameter>();
        using (Microsoft.Data.SqlClient.SqlDataReader reader = DBManager.ExecuteReaderMS(sql, parameters.ToArray()))
        {
            while (reader.Read())
            ssn = Convert.ToString(reader["SSN"]);
        }
    }
    catch (Exception e)
    {
        string error = e.ToString();
    }
    return ssn;
}

Example of Azure Function

[FunctionName("TestFunction")]
public static Task Run([ServiceBusTrigger("testfunction", Connection = "testconnection")]Message myQueueItem, ILogger log)
{
    try
    {
        string aType = Convert.ToString(myQueueItem.UserProperties["type"]);
        string aResourceName = Convert.ToString(myQueueItem.UserProperties["name"]);
        int aResult = 0;
        string aMessage = null;
        if (aType == "AKVTEST") 
        {
            string anSSN = ProjectA.ClassA.MethodA();
            return Task.CompletedTask;
        }

        log.LogInformation($"C# ServiceBus queue trigger function processed message: {myQueueItem.Body} for type: {aType}");
        return null;
    }
    catch (Exception Ex)
    {
        log.LogInformation($"C# ServiceBus queue trigger function EXCEPTION: {Ex.ToString()}");
        return null;
    }
}

Tried to change System.Data.SqlClient reference to Microsoft.Data.SqlClient (package version 5.1) and we received the exception mentioned above.

Before this change, while using System.Data.SqlClient, we were getting the following exception:

System.ArgumentException: 'Keyword not supported: 'column encryption setting'.'

Note: We have been using this set up in our production without the column encryption and have had no issues until trying to add this feature.

Accessing always encrypted column on azure function using reference methods

0 Answers0