/// <summary>
/// Backs up each hangfire.mongo collection before executing migration
/// </summary>
/// <param name="storageOptions"></param>
/// <param name="database"></param>
/// <param name="fromSchema"></param>
/// <param name="toSchema"></param>
/// <exception cref="InvalidOperationException"></exception>
public override void Backup(MongoStorageOptions storageOptions, IMongoDatabase database, MongoSchema fromSchema, MongoSchema toSchema)
{
var existingCollectionNames = MongoMigrationUtils.ExistingHangfireCollectionNames(database, fromSchema, storageOptions).ToList();
var backupCollectionNames =
existingCollectionNames
.ToDictionary(k => k, v =>
MongoMigrationUtils.GetBackupCollectionName(v, fromSchema, storageOptions));
// Let's double check that we have not backed up before.
var existingBackupCollectionName = existingCollectionNames.FirstOrDefault(n => backupCollectionNames.ContainsValue(n));
if (existingBackupCollectionName != null)
{
throw new InvalidOperationException(
$"{Environment.NewLine}{existingBackupCollectionName} already exists. Cannot perform backup." +
$"{Environment.NewLine}Cannot overwrite existing backups. Please resolve this manually (e.g. by droping collection)." +
$"{Environment.NewLine}Please see https://github.com/sergeyzwezdin/Hangfire.Mongo#migration for further information.");
}
// Now do the actual backup
foreach (var collection in backupCollectionNames)
{
BackupCollection(database, collection.Key, collection.Value);
}
}
/// <summary>
/// drop all hangfire collections
/// </summary>
/// <param name="database"></param>
/// <param name="fromSchema"></param>
/// <param name="toSchema"></param>
protected override void ExecuteStrategy(IMongoDatabase database, MongoSchema fromSchema, MongoSchema toSchema)
{
foreach (var collectionName in MongoMigrationUtils.ExistingHangfireCollectionNames(database, fromSchema, StorageOptions))
{
database.DropCollection(collectionName);
}
}