/// <summary>
/// Add a new collection. Check if name the not exists. Create only in transaction page - will update header only in commit
/// </summary>
private void Add(string name, ref CollectionPage collectionPage)
{
if (Encoding.UTF8.GetByteCount(name) > _header.GetAvaiableCollectionSpace())
{
throw LiteException.InvalidCollectionName(name, "There is no space in header for more collections");
}
if (!name.IsWord())
{
throw LiteException.InvalidCollectionName(name, "Use only [a-Z$_]");
}
if (name.StartsWith("$"))
{
throw LiteException.InvalidCollectionName(name, "Collection can't starts with `$` (reserved for system collections)");
}
// create new collection page
collectionPage = _snapshot.NewPage <CollectionPage>();
var pageID = collectionPage.PageID;
// insert collection name/pageID in header only in commit operation
_transPages.Commit += (h) => h.InsertCollection(name, pageID);
// create first index (_id pk) (must pass collectionPage because snapshot contains null in CollectionPage prop)
var indexer = new IndexService(_snapshot);
indexer.CreateIndex("_id", "$._id", true);
}
/// <summary>
/// Rename a collection (do not support transactions)
/// </summary>
public bool RenameCollection(string collection, string newName)
{
if (collection.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(collection));
}
if (newName.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(newName));
}
// rename collection is possible only in exclusive transaction for this
if (_locker.IsInTransaction)
{
throw LiteException.AlreadyExistsTransaction();
}
// check for collection name
if (collection.Equals(newName, StringComparison.OrdinalIgnoreCase))
{
throw LiteException.InvalidCollectionName(newName, "New name must be different from current name");
}
// checks if newName are compatible
CollectionService.CheckName(newName, _header);
// rename collection is possible only in exclusive transaction for this
if (_locker.IsInTransaction)
{
throw LiteException.AlreadyExistsTransaction();
}
return(this.AutoTransaction(transaction =>
{
var currentSnapshot = transaction.CreateSnapshot(LockMode.Write, collection, false);
var newSnapshot = transaction.CreateSnapshot(LockMode.Write, newName, false);
if (currentSnapshot.CollectionPage == null)
{
return false;
}
// checks if do not already exists this collection name
if (_header.GetCollectionPageID(newName) != uint.MaxValue)
{
throw LiteException.AlreadyExistsCollectionName(newName);
}
// rename collection and set page as dirty (there is no need to set IsDirty in HeaderPage)
transaction.Pages.Commit += (h) =>
{
h.RenameCollection(collection, newName);
};
return true;
}));
}
/// <summary>
/// Check collection name if is valid (and fit on header)
/// Throw correct message error if not valid name or not fit on header page
/// </summary>
public static void CheckName(string name, HeaderPage header)
{
if (Encoding.UTF8.GetByteCount(name) > header.GetAvaiableCollectionSpace())
{
throw LiteException.InvalidCollectionName(name, "There is no space in header this collection name");
}
if (!name.IsWord())
{
throw LiteException.InvalidCollectionName(name, "Use only [a-Z$_]");
}
if (name.StartsWith("$"))
{
throw LiteException.InvalidCollectionName(name, "Collection can't starts with `$` (reserved for system collections)");
}
}