persistence/DD.Persistence.Database.Postgres/Services/ArchiveService.cs

using DD.Persistence.Services.Interfaces;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using Npgsql;

namespace DD.Persistence.Database.Postgres.Services;

/// <summary>
/// Сервис по работе с источником данных - базой postgres
/// </summary>
public class PostgresArchiveService : IArchiveService
{
    private string connectionString;
    private ILogger<PostgresArchiveService> logger;

    /// <summary>
    /// Сервис по работе с источником данных - базой postgres
    /// </summary>
    /// <param name="configuration"></param>
    public PostgresArchiveService(IConfiguration configuration, ILogger<PostgresArchiveService> logger)
    {
        this.connectionString = configuration.GetConnectionString("SystemBaseConnection")!;
        this.logger = logger;
    }
    public Task Create(string newName, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public async Task Rename(string newName, CancellationToken token)
    {
        await using var connection = new NpgsqlConnection(connectionString);
        try
        {
            await connection.OpenAsync();

            var sqlCloseConnect =
                $"SELECT pg_terminate_backend(pg_stat_activity.pid) " +
                $"FROM pg_stat_activity " +
                $"WHERE pg_stat_activity.datname = 'persistence' AND pid <> pg_backend_pid();";
            await using var command = new NpgsqlCommand(sqlCloseConnect, connection);
            await command.ExecuteNonQueryAsync();

            var rename = $"ALTER DATABASE persistence RENAME TO {newName};";
            await using var sqlRenameDatabase = new NpgsqlCommand(rename, connection);
            await sqlRenameDatabase.ExecuteNonQueryAsync();
        }
        catch (NpgsqlException exception)
        {
            this.logger.LogError(exception.Message);
            throw;
        }

    }
}