why seeded roles are deleted on every migration in asp .net core 2.1?

Question

I am getting a strange behavior of seeded roles on every migration. No matter what changes you have made, migration will delete the seeded roles and will insert them again. Migration given below is created when no modification is done in the project.

All other models are seeded correctly and are considered in migration only if they are modified.

I am using ASP .NET Core 2.1 with Individual Authentication

DbContext Class for seeding

 public class ApplicationDbContext : IdentityDbContext
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        #region Seed-Roles

        modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "SuperAdmin", NormalizedName = "SuperAdmin".ToUpper() });
        modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "Owner", NormalizedName = "Owner".ToUpper() });
        modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "Admin", NormalizedName = "Admin".ToUpper() });
        modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "Tester", NormalizedName = "Tester".ToUpper() });
        modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "User", NormalizedName = "User".ToUpper() });
        modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "Developer", NormalizedName = "Developer".ToUpper() });

        #endregion
    }
}

Migration

protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "4ae1956e-7895-4b0f-a390-22b5c41c1a62", "67b6f36e-5a3c-456b-89ef-c667cf9fe0d3" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "55ebaa87-e350-4d88-8d6f-2c7d833dd24d", "ed91ae85-918f-4651-b7f9-42f6dd90d9b2" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "6ae683e2-5df3-425f-8df7-66581ce56259", "6a4ff0dc-f82f-4c8d-85a1-0258bbf905d7" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "b06b021d-b369-44b3-a5d9-eeb3ef8e245d", "1363d06f-a0cb-4d10-8495-866c219f5560" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "b5331aad-70ec-47a2-8dd0-bc2508bdc353", "ae98d41a-e8fa-46dd-b081-96f9a1934e1e" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "b9fec2b5-6fd2-46a5-a960-a8d26f16d269", "413922ea-76f0-4d2d-8f1a-d9157fb31df0" });

        migrationBuilder.InsertData(
            table: "AspNetRoles",
            columns: new[] { "Id", "ConcurrencyStamp", "Name", "NormalizedName" },
            values: new object[,]
            {
                { "34e62595-2afc-43f9-bbcd-267773129d69", "c47b3378-ef47-4661-8a01-ceb2fbe34d7c", "SuperAdmin", "SUPERADMIN" },
                { "bc020d73-e415-4d4e-8dfe-577d81755f80", "77d4f05b-6677-4e99-9ada-3f6ec083c14b", "Owner", "OWNER" },
                { "cbfdbeb0-f800-4b42-b735-db1449fcc4e4", "2b8f6650-e2ee-46c1-a70f-36725fb893b3", "Admin", "ADMIN" },
                { "cd0e178d-f9cb-448e-8ecc-49914aa63c5d", "23ee6cfe-4bc2-4c6c-847a-d03aa0087e1f", "Tester", "TESTER" },
                { "4572a259-0d7c-4d1c-ad1d-e0230b7dd1fb", "bcc79860-9207-42bd-8a9c-8aeef0b5fe56", "User", "USER" },
                { "334fd762-7f37-48aa-afdc-a87ef8d0593e", "d929467e-44be-4a94-912f-071702316c85", "Developer", "DEVELOPER" }
            });
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "334fd762-7f37-48aa-afdc-a87ef8d0593e", "d929467e-44be-4a94-912f-071702316c85" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "34e62595-2afc-43f9-bbcd-267773129d69", "c47b3378-ef47-4661-8a01-ceb2fbe34d7c" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "4572a259-0d7c-4d1c-ad1d-e0230b7dd1fb", "bcc79860-9207-42bd-8a9c-8aeef0b5fe56" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "bc020d73-e415-4d4e-8dfe-577d81755f80", "77d4f05b-6677-4e99-9ada-3f6ec083c14b" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "cbfdbeb0-f800-4b42-b735-db1449fcc4e4", "2b8f6650-e2ee-46c1-a70f-36725fb893b3" });

        migrationBuilder.DeleteData(
            table: "AspNetRoles",
            keyColumns: new[] { "Id", "ConcurrencyStamp" },
            keyValues: new object[] { "cd0e178d-f9cb-448e-8ecc-49914aa63c5d", "23ee6cfe-4bc2-4c6c-847a-d03aa0087e1f" });

        migrationBuilder.InsertData(
            table: "AspNetRoles",
            columns: new[] { "Id", "ConcurrencyStamp", "Name", "NormalizedName" },
            values: new object[,]
            {
                { "6ae683e2-5df3-425f-8df7-66581ce56259", "6a4ff0dc-f82f-4c8d-85a1-0258bbf905d7", "SuperAdmin", "SUPERADMIN" },
                { "55ebaa87-e350-4d88-8d6f-2c7d833dd24d", "ed91ae85-918f-4651-b7f9-42f6dd90d9b2", "Owner", "OWNER" },
                { "4ae1956e-7895-4b0f-a390-22b5c41c1a62", "67b6f36e-5a3c-456b-89ef-c667cf9fe0d3", "Admin", "ADMIN" },
                { "b5331aad-70ec-47a2-8dd0-bc2508bdc353", "ae98d41a-e8fa-46dd-b081-96f9a1934e1e", "Tester", "TESTER" },
                { "b9fec2b5-6fd2-46a5-a960-a8d26f16d269", "413922ea-76f0-4d2d-8f1a-d9157fb31df0", "User", "USER" },
                { "b06b021d-b369-44b3-a5d9-eeb3ef8e245d", "1363d06f-a0cb-4d10-8495-866c219f5560", "Developer", "DEVELOPER" }
            });
    }

If i'm doing it wrong please update me what is the correct behavior of seeding roles.

Answer 1

As Zubair Rana mentioned, if you want to use this method of seeding data in OnModelCreating method for Entity Framework .net Core then you have to seed complete object fields! not just the key field, here is my code example for seeding IdentityRole:

modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Id = "117d1b41-6753-4622-89e6-8126a3b7d3f0", ConcurrencyStamp = "da7a4f42-ff3c-42a8-935a-62af68f978b0", Name = "Admin", NormalizedName = "Admin".ToUpper() });

if you do it like below:

 modelBuilder.Entity<IdentityRole>().HasData(new IdentityRole { Name = "Admin", NormalizedName = "Admin".ToUpper() });

then at each migration the ef will keep delete old objects and fill it again with same "Name" & "NormalizedName" but the "Id" & "ConcurrencyStamp" will generated again with new values.

Answer 2

Rather than hardcoding the Id and ConcurrencyStamp to work around this issue, you can follow the following steps:

1. Create an initial migration which will seed the roles

2. Remove the seeding logic for Roles from your OnModelCreating code (i.e. the HasData)

3. Create another migration. This will have logic to delete the Roles on Up and add the Roles on Down that looks like this:

   migrationBuilder.DeleteData(
       table: "AspNetRoles",
       keyColumn: "Id",
       keyValue: "1");
   
   ...
   
   migrationBuilder.InsertData(
       table: "AspNetRoles",
       columns: new[] { "Id", "ConcurrencyStamp", "Name", "NormalizedName" },
       values: new object[,]
       {
           { "1", "...GUID...", "MyRole", "MYROLE" },
       });
   

Remove this code inside the migration. The migration will still exist, but will do nothing.

Basically your initial migration will create the data (and delete it on down) and then migrations moving forward don't muck around with the seeding.