/// <summary>
/// Polls until this table contains at least the given number of rows. This should be used carefully, only where we know the table won't be huge.
/// </summary>
/// <remarks>
/// <para>
/// This method is designed to make integration tests more reliable: after an insert, data fetching (with queries or ListRows)
/// may not see the new data.
/// </para>
/// <para>
/// We've tried using the data in BigQueryTable.Resource.NumRows and BigQueryTable.Resource.StreamingBuffer, but they're not as reliable as
/// just reading the rows.
/// </para>
/// </remarks>
/// <param name="expectedRows">The number of rows expected.</param>
/// <param name="pollSettings">The poll settings to use, or null to use the defaults (poll once every 2 seconds, 30 second timeout)</param>
/// <returns>The actual number of rows in the table.</returns>
/// <exception cref="TimeoutException">The timeout specified in the poll settings elapsed before the streaming buffer became empty.</exception>
public static int PollUntilRowCountIsAtLeast(this BigQueryTable table, int expectedRows, PollSettings pollSettings = null) =>
Polling.PollRepeatedly(
ignoredDeadline => table.ListRows().Count(),
count => count >= expectedRows,
SystemClock.Instance,
SystemScheduler.Instance,
pollSettings ?? s_defaultStreamingBufferPollSettings,
CancellationToken.None);
internal void InsertAndWait(BigQueryTable table, Action insertAction, int expectedRowCountChange)
{
var countBefore = table.ListRows().Count();
var expectedCount = countBefore + expectedRowCountChange;
insertAction();
// Wait until there are *at least* enough rows
int actualCount = table.PollUntilRowCountIsAtLeast(expectedCount);
// Now check it's *exactly* the right number of rows.
Assert.Equal(expectedCount, actualCount);
}
public void ListRows()
{
string projectId = _fixture.ProjectId;
string datasetId = _fixture.GameDatasetId;
string tableId = _fixture.HistoryTableId;
// Snippet: ListRows
BigQueryClient client = BigQueryClient.Create(projectId);
BigQueryTable table = client.GetTable(datasetId, tableId);
PagedEnumerable <TableDataList, BigQueryRow> result = table.ListRows();
foreach (BigQueryRow row in result)
{
DateTime timestamp = (DateTime)row["game_started"];
long level = (long)row["level"];
long score = (long)row["score"];
string player = (string)row["player"];
Console.WriteLine($"{player}: {level}/{score} ({timestamp:yyyy-MM-dd HH:mm:ss})");
}
// End snippet
// We set up 7 results in the fixture. Other tests may add more.
Assert.True(result.Count() >= 7);
}