Infrastructure added in User managment api project to acquire db lock by connection to master db for executing migrations

Author: HasanJaved-Developer

UserManagementApi/Infrastructure/MigrationWithLockExtensions.cs

@@ -0,0 +1,43 @@
+using Microsoft.Data.SqlClient;
+using Microsoft.EntityFrameworkCore;
+
+namespace UserManagementApi.Infrastructure
+{
+    public static class MigrationWithLockExtensions
+    {
+        /// <summary>
+        /// Acquires a SQL app-lock, then runs EF Migrate() and your seed delegate.
+        /// Use the SAME lock name across ALL services hitting the same SQL Server.
+        /// </summary>
+        public static async Task MigrateAndSeedWithSqlLockAsync<TContext>(
+            this IHost app,
+            string connectionStringName,                       // e.g. "Default"
+            string globalLockName,                             // e.g. "IMIS_GLOBAL_MIGRATE_SEED"
+            Func<IServiceProvider, CancellationToken, Task> seedAsync,
+            CancellationToken ct = default)
+            where TContext : DbContext
+        {
+            using var scope = app.Services.CreateScope();
+            var services = scope.ServiceProvider;
+
+            var cfg = services.GetRequiredService<IConfiguration>();
+            var logger = services.GetRequiredService<ILogger<TContext>>();
+            var db = services.GetRequiredService<TContext>();
+
+            // Build a **master** connection string on the same server
+            var csb = new SqlConnectionStringBuilder(cfg.GetConnectionString(connectionStringName));
+            var master = new SqlConnectionStringBuilder(csb.ConnectionString) { InitialCatalog = "master"}.ToString();
+
+            await SqlAppLock.WithExclusiveLockAsync(master, globalLockName, async token =>
+            {
+                logger.LogInformation("Applying EF migrations for DB '{Db}'...", csb.InitialCatalog);
+                await db.Database.MigrateAsync(token);   // creates DB if missing, applies migrations
+                logger.LogInformation("Migrations OK for '{Db}'. Seeding...", csb.InitialCatalog);
+
+                await seedAsync(services, token);        // call your existing seeder here
+
+                logger.LogInformation("Seed completed for '{Db}'.", csb.InitialCatalog);
+            }, ct: ct);
+        }
+    }
+}

UserManagementApi/Infrastructure/SqlAppLock.cs

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+using Microsoft.Data.SqlClient;
+using System.Data;
+
+namespace UserManagementApi.Infrastructure
+{
+    public static class SqlAppLock
+    {
+        public static async Task WithExclusiveLockAsync(
+            string masterConnectionString,
+            string resourceName,
+            Func<CancellationToken, Task> action,
+            int timeoutMs = 60000,
+            CancellationToken ct = default)
+        {
+            await using var conn = new SqlConnection(masterConnectionString);
+            await conn.OpenAsync(ct);
+
+            // Acquire lock
+            await using (var cmd = new SqlCommand("sp_getapplock", conn) { CommandType = CommandType.StoredProcedure })
+            {
+                cmd.Parameters.AddWithValue("@Resource", resourceName);
+                cmd.Parameters.AddWithValue("@LockMode", "Exclusive");
+                cmd.Parameters.AddWithValue("@LockOwner", "Session");
+                cmd.Parameters.AddWithValue("@LockTimeout", timeoutMs); // <-- correct name
+
+                var ret = cmd.Parameters.Add("@RETURN_VALUE", SqlDbType.Int);
+                ret.Direction = ParameterDirection.ReturnValue;
+
+                await cmd.ExecuteNonQueryAsync(ct);
+
+                var code = (int)(ret.Value ?? -999);
+                // 0 = success, 1 = already held by caller; negatives are failure
+                if (code < 0)
+                    throw new TimeoutException($"sp_getapplock failed ({code}) for '{resourceName}'.");
+            }
+
+            try
+            {
+                await action(ct);
+            }
+            finally
+            {
+                // Release lock
+                await using var rel = new SqlCommand("sp_releaseapplock", conn) { CommandType = CommandType.StoredProcedure };
+                rel.Parameters.AddWithValue("@Resource", resourceName);
+                rel.Parameters.AddWithValue("@LockOwner", "Session");
+                await rel.ExecuteNonQueryAsync(ct);
+            }
+        }
+    }
+}