how to execute SQL code separatly in SqlServerMigrationSqlGenerator Generates method? - entity-framework-6

Question

I want to run an SQL script after each new table created through Entity Framework.
I created an override for 'CreateTableOperation' like this:
protected override void Generate(CreateTableOperation createTableOperation)
{
string tenantID = "tenantID";
base.Generate(createTableOperation);
//If the table contain the column "tenantID",
if ((from x in createTableOperation.Columns
where x.Name == tenantID
select x).Any()
)
{
//Add the Security Policies for this table
using (var writer = Writer())
{
writer.WriteLine("ALTER SECURITY POLICY rls.tenantAccessPolicy ");
//Note: dbo. is already part of the .Name, don't add it manually before .Name
writer.WriteLine($"ADD FILTER PREDICATE rls.fn_tenantAccessPredicateWithSuperUser([{tenantID}]) ON [{createTableOperation.Name}], ");
writer.WriteLine($"ADD BLOCK PREDICATE rls.fn_tenantAccessPredicateWithSuperUser([{tenantID}]) ON [{createTableOperation.Name}] ");
Statement(writer);
}
}
}
Let's say I create a new class 'TEST'.
The problem is when I run my Update-Database in the Package Manager Console, the SQL is executed in one big block and create an error because the table is not yet created and I'm trying to get the table.name Package Manager result after Update-Database:
CREATE TABLE [dbo].[TEST] (
[ID] [int] NOT NULL IDENTITY,
[NameTEST] [nvarchar](max),
[TenantID] [int] NOT NULL,
CONSTRAINT [PK_dbo.TEST] PRIMARY KEY ([ID])
)
ALTER SECURITY POLICY rls.tenantAccessPolicy
ADD FILTER PREDICATE rls.fn_tenantAccessPredicateWithSuperUser([tenantID]) ON [dbo.TEST],
ADD BLOCK PREDICATE rls.fn_tenantAccessPredicateWithSuperUser([tenantID]) ON [dbo.TEST]
Cannot find the object "dbo.TEST" because it does not exist or you do not have permissions.
Is there a way to break between the base.Generate(createTableOperation); and my Statement(writer);? (I already tried multiple things with 'GO' without much success). Or is it that I'm not supposed to put code in that method?

Answer 1

I couldn't find a solution/documentation to separate the code/batch SQL in Generate(CreateTableOperation createTableOperation).
What I did instead was to
generate dynamic SQL scripts in the Generate(CreateTableOperation createTableOperation) method
/// <summary>
/// Generate dynamically named .sql file for CREATE and DROP Security Policies (Row-Level Security (Company can't see/insert data of another company))
/// </summary>
/// <param name="createTableOperation">Default parameter that comes with the override method.</param>
protected override void Generate(CreateTableOperation createTableOperation)
{
base.Generate(createTableOperation);
string fullFolderPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "..\\Migrations\\SQLscripts\\SecurityPolicies");
//Remove the schema for the dynamic creation of the .sql filename else it throw an exception:
int indexOfDot = createTableOperation.Name.IndexOf(".");
indexOfDot++; //Because it's 0 base, add 1 char
string tableNameWithoutSchema = (indexOfDot < 0) ? createTableOperation.Name : createTableOperation.Name.Remove(0, indexOfDot);
string filePathCreate = Path.Combine(fullFolderPath, $"CreateSecurityPolicies_{tableNameWithoutSchema}.sql");
string filePathDrop = Path.Combine(fullFolderPath, $"DropSecurityPolicies_{tableNameWithoutSchema}.sql");
//If .sql files doesn't exists, create them
if (!File.Exists(filePathCreate))
{
using (StreamWriter sw = new StreamWriter(filePathCreate, true))
{
sw.WriteLine("ALTER SECURITY POLICY rls.tenantAccessPolicy");
//Note: Don't concatenate 'dbo.{}' because 'createTableOperation.Name' already include 'dbo'
sw.WriteLine($" ADD FILTER PREDICATE rls.fn_tenantAccessPredicateWithSuperUser(CompanyID) ON {createTableOperation.Name},");
sw.WriteLine($" ADD BLOCK PREDICATE rls.fn_tenantAccessPredicateWithSuperUser(CompanyID) ON {createTableOperation.Name}");
sw.WriteLine("GO");
sw.Close();
}
}
if (!File.Exists(filePathDrop))
{
using (StreamWriter sw = new StreamWriter(filePathDrop, true))
{
sw.WriteLine("ALTER SECURITY POLICY rls.tenantAccessPolicy");
sw.WriteLine($" DROP FILTER PREDICATE ON {createTableOperation.Name},");
sw.WriteLine($" DROP BLOCK PREDICATE ON {createTableOperation.Name}");
sw.WriteLine("GO");
sw.Close();
}
}
}
Then, with my SQL scripts in a folder, add it manually to my solution.
Add-Migration just to run my SQL script by adding code into the empty (up-to-date) migration class.
public override void Up()
{
string sqlFilePath = System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "..\\Migrations\\SQLscripts\\CreateSecurityPolicies_Client.sql");
string sqlText = System.IO.File.ReadAllText(sqlFilePath);
Sql(sqlText);
}
public override void Down()
{
string sqlFilePath = System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "..\\Migrations\\SQLscripts\\DropSecurityPolicies_Client.sql");
string sqlText = System.IO.File.ReadAllText(sqlFilePath);
Sql(sqlText);
}
This is the best I can come up with for the moment. I hope it can helps other EntityFramework programmers!