public void TestDatabaseBackedMemoryStream()
{
var prepared = TestHelper.PrepareDatabaseAndBlob(this.testFile.FullName, this.random);
using (var connection = new SqliteConnection(prepared.ConnectionString))
{
connection.Open();
TestHelper.AssertBlobMetadata(connection, 1024, 0, 0, 0);
var now = Date.Now;
using (var stream = new DatabaseBackedMemoryStream(connection, UPath.Root / "test.blob", true, true))
{
TestHelper.AssertBlobMetadata(connection, 1024, now, 0, 0);
Assert.IsTrue(stream.CanRead);
Assert.IsTrue(stream.CanSeek);
Assert.IsTrue(stream.CanWrite);
Assert.AreEqual(0, stream.Position);
Assert.AreEqual(1024, stream.Length);
var actualBlob = new byte[stream.Length];
var read = stream.Read(actualBlob, 0, 1024);
Assert.AreEqual(1024, read);
CollectionAssert.AreEqual(prepared.blobData, actualBlob);
}
// the meta data should not have been updated because no changes were made
TestHelper.AssertBlobMetadata(connection, 1024, now, 0, 0);
}
}
public void TestDatabaseBackedMemoryStreamWriting()
{
var prepared = TestHelper.PrepareDatabaseAndBlob(this.testFile.FullName, this.random);
var additionalBytes = new byte[512];
this.random.NextBytes(additionalBytes);
using (var connection = new SqliteConnection(prepared.ConnectionString))
{
connection.Open();
using (var stream = new DatabaseBackedMemoryStream(connection, UPath.Root / "test.blob", true, true))
{
// we're going to append extra data onto the stream
stream.Seek(0, SeekOrigin.End);
Assert.AreEqual(1024, stream.Position);
Assert.AreEqual(1024, stream.Length);
stream.Write(additionalBytes, 0, 256);
Assert.AreEqual(1024 + 256, stream.Position);
Assert.AreEqual(1024 + 256, stream.Length);
// no changes should have happened to the database
AssertDatabaseBlobLength(connection, 1024);
// when changes are flushed we expect an update
stream.Flush();
Assert.AreEqual(1024 + 256, stream.Position);
Assert.AreEqual(1024 + 256, stream.Length);
AssertDatabaseBlobLength(connection, 1024 + 256);
// write another set of bytes
stream.Write(additionalBytes, 256, 256);
Assert.AreEqual(1024 + 512, stream.Position);
Assert.AreEqual(1024 + 512, stream.Length);
// no flush, so no db update
AssertDatabaseBlobLength(connection, 1024 + 256);
}
// dispose should flush
AssertDatabaseBlobLength(connection, 1024 + 512);
}
}
