void ThrowIfAnyDowngradeNotSupported()
{
if (Migrations.Any(m => !m.CanDowngrade))
{
throw new NotSupportedException("One or more migrations do not support downgrading.");
}
}
public void UseMigrations(IReadOnlyList <Migration> migrations)
{
Migrations = migrations.OrderBy(x => x.Version).Where((x, i) =>
{
var expectedVersion = i + 1;
if (x.Version == expectedVersion)
{
return(true);
}
throw new ArgumentException($"Missing migration for version {expectedVersion}.");
}).ToList();
ConfiguredVersion = Migrations.Any() ? Migrations.Last().Version : 0;
}
private void LoadMigrationsIfNotLoaded()
{
if (Migrations != null)
{
return;
}
lock (_migrationsResolver)
{
if (Migrations != null)
{
return;
}
Migrations = _migrationsResolver.Resolve()
.OrderBy(x => x.Version)
.ToList();
LatestSchemaVersion = Migrations.Any() ? Migrations.Max(x => x.Version) : 0;
}
Interceptor?.DetectedMigrations(Migrations.ToArray(), LatestSchemaVersion);
}
/// <summary>
/// Upgrade/downgrade to the specified version.
/// </summary>
/// <param name="version">
/// The required version of the repository.
/// </param>
/// <param name="cancel">
/// </param>
/// <returns></returns>
public async Task MirgrateToVersionAsync(int version, CancellationToken cancel = default(CancellationToken))
{
if (version != 0 && !Migrations.Any(m => m.Version == version))
{
throw new ArgumentOutOfRangeException("version", $"Repository version '{version}' is unknown.");
}
var currentVersion = CurrentVersion;
var increment = CurrentVersion < version ? 1 : -1;
while (currentVersion != version)
{
var nextVersion = currentVersion + increment;
log.InfoFormat("Migrating to version {0}", nextVersion);
if (increment > 0)
{
var migration = Migrations.FirstOrDefault(m => m.Version == nextVersion);
if (migration.CanUpgrade)
{
await migration.UpgradeAsync(ipfs, cancel);
}
}
else if (increment < 0)
{
var migration = Migrations.FirstOrDefault(m => m.Version == currentVersion);
if (migration.CanDowngrade)
{
await migration.DowngradeAsync(ipfs, cancel);
}
}
CurrentVersion = nextVersion;
currentVersion = nextVersion;
}
}
