public IndexHeaderData Read()
{
var buffer = new byte[1024];
int read = persistentStorage.Read(0, buffer, 0, buffer.Length);
if (read == 0)
{
return(null);
}
using (var reader = new StringReader(System.Text.Encoding.UTF8.GetString(buffer, 0, read)))
{
var result = new IndexHeaderData
{
Type = reader.ReadLine(),
MaxTokenSize = int.Parse(reader.ReadLine()),
NextDocumentId = ulong.Parse(reader.ReadLine()),
CreatedDate = DateTime.Parse(reader.ReadLine()),
ModifiedDate = DateTime.Parse(reader.ReadLine()),
};
while (true)
{
var line = reader.ReadLine();
if (line == null)
{
break;
}
result.Settings.Add(line);
}
return(result);
}
}
public InMemoryIndex()
{
Header = new IndexHeaderData
{
Type = nameof(InMemoryIndex),
MaxTokenSize = MaxTokenSize,
NextDocumentId = 0,
CreatedDate = DateTime.UtcNow,
ModifiedDate = DateTime.UtcNow,
};
}
protected override IFullTextIndexHeader GetIndexHeader()
{
var header = indexInfo.Read();
var dictionaryType = PersistentDictionaryFactory.GetName(name.DictionaryType);
var fieldsType = PersistentMetadataFactory.GetName(name.FieldsType);
var postingType = PostingListIOFactory.GetName(name.PostingType);
var textEncoding = TextEncodingFactory.GetName(name.TextEncoding);
if (header == null)
{
header = new IndexHeaderData
{
Type = $"{nameof(PersistentIndex)} {dictionaryType} {fieldsType} {postingType} {textEncoding}",
MaxTokenSize = MaxTokenSize,
NextDocumentId = 0,
CreatedDate = DateTime.UtcNow,
ModifiedDate = DateTime.UtcNow,
};
}
else
{
var types = header.Type.Split(' ');
if (types[0] != nameof(PersistentIndex))
{
throw new InvalidOperationException("Index type and name mismatch");
}
if (types[1] != dictionaryType)
{
throw new InvalidOperationException("Field type and name mismatch");
}
if (types[2] != fieldsType)
{
throw new InvalidOperationException("Field type and name mismatch");
}
if (types[3] != postingType)
{
throw new InvalidOperationException("Posting type and name mismatch");
}
if (types[4] != textEncoding)
{
throw new InvalidOperationException("Text encoding type and name mismatch");
}
}
return(header);
}