public ByteString ToGprcArrowFrame()
{
MemoryStream stream = new MemoryStream();
var recordBatchBuilder = new RecordBatch.Builder();
foreach (Field field in fields)
{
recordBatchBuilder.Append(field.Name, true, field.ToArrowArray());
}
var recordBatch = recordBatchBuilder.Build();
var writer = new ArrowFileWriter(stream, recordBatch.Schema);
writer.WriteRecordBatch(recordBatch);
writer.WriteEnd();
stream.Position = 0;
return(ByteString.FromStream(stream));
}
public async Task WritesEmptyFile()
{
RecordBatch originalBatch = TestData.CreateSampleRecordBatch(length: 1);
var stream = new MemoryStream();
var writer = new ArrowFileWriter(stream, originalBatch.Schema);
writer.WriteStart();
writer.WriteEnd();
stream.Position = 0;
var reader = new ArrowFileReader(stream);
int count = await reader.RecordBatchCountAsync();
Assert.Equal(0, count);
RecordBatch readBatch = reader.ReadNextRecordBatch();
Assert.Null(readBatch);
SchemaComparer.Compare(originalBatch.Schema, reader.Schema);
}
public async Task WritesFooterAlignedMulitpleOf8()
{
RecordBatch originalBatch = TestData.CreateSampleRecordBatch(length: 100);
var stream = new MemoryStream();
var writer = new ArrowFileWriter(
stream,
originalBatch.Schema,
leaveOpen: true,
// use WriteLegacyIpcFormat, which only uses a 4-byte length prefix
// which causes the length prefix to not be 8-byte aligned by default
new IpcOptions()
{
WriteLegacyIpcFormat = true
});
writer.WriteRecordBatch(originalBatch);
writer.WriteEnd();
stream.Position = 0;
await ValidateRecordBatchFile(stream, originalBatch);
}