public void ApplicationLogsReaderWillNotOpenUnlimitedNumberOfFiles()
{
// This test would preferrably use a mocked file system but the System.IO.Abstractions.TestHelpers have
// some issues with returning the correct LastWrittenUtc and so this needs to run against a real file system for now.
var fs = new FileSystem();
FileSystemHelpers.Instance = fs;
using (var dir = new TemporaryApplicationLogDirectory(fs))
{
var logFileCount = 100;
var timestamp = DateTimeOffset.UtcNow;
for (int i = 0; i < logFileCount; i++)
{
timestamp = timestamp.AddSeconds(1);
dir.AddLogFile(
string.Format("log-{0}.txt", i),
string.Format("{0:s} PID[20108] Information this is a log\r\n", timestamp)
);
}
var env = new ApplicationLogsTestEnvironment(dir.RootDir);
var reader = new ApplicationLogsReader(env, Mock.Of <ITracer>());
var results = reader.GetRecentLogs(logFileCount).ToList();
// In this degenerate case with a large number of log files with only one line each, the limit
// on the number of log files that can be read will be hit and so not all 100 log entries will
// be returned.
Assert.Equal(ApplicationLogsReader.FileOpenLimit, results.Count);
results[0].AssertLogEntry(timestamp.ToString("s"), "Information", "this is a log");
}
}
public void ResumableLogReaderCanReadFromFilesOpenForWriting()
{
var fs = new FileSystem();
FileSystemHelpers.Instance = fs;
using (var dir = new TemporaryApplicationLogDirectory(fs))
{
var logFile = dir.AddLogFile("log-1.txt", "2013-12-06T00:29:20 PID[20108] Information this is a log\r\n");
using (var writer = new StreamWriter(fs.File.Open(logFile.FullName, FileMode.Append, FileAccess.Write, FileShare.ReadWrite))
{
AutoFlush = true
})
using (var reader = new ApplicationLogsReader.ResumableLogFileReader(logFile, Mock.Of <ITracer>()))
{
writer.WriteLine("2013-12-06T00:29:21 PID[20108] Warning this is a warning");
var results = reader.ReadNextBatch(1);
Assert.Equal(1, results.Count);
results[0].AssertLogEntry("2013-12-06T00:29:21+00:00", "Warning", "this is a warning");
writer.WriteLine("2013-12-06T00:29:22 PID[20108] Error this is an error");
results = reader.ReadNextBatch(1);
Assert.Equal(1, results.Count);
results[0].AssertLogEntry("2013-12-06T00:29:20+00:00", "Information", "this is a log");
}
}
}
public void ApplicationLogsReaderReturnsTheCorrectResultsWhenAccessedByMultipleThreads()
{
var fs = new FileSystem();
FileSystemHelpers.Instance = fs;
using (var dir = new TemporaryApplicationLogDirectory(fs))
{
dir.AddLogFile("log-1.txt",
@"2013-12-06T00:29:20 PID[20108] Information this is a log
2013-12-06T00:29:21 PID[20108] Warning this is a warning
2013-12-06T00:29:22 PID[20108] Error this is an error"
);
dir.AddLogFile("log-2.txt",
@"2013-12-06T00:29:20 PID[20108] Information this is a log
2013-12-06T00:29:21 PID[20108] Warning this is a warning
2013-12-06T00:29:22 PID[20108] Error this is an error"
);
dir.AddLogFile("log-3.txt", @"2014-01-09T00:18:30 NOT A VALID LOG FILE");
dir.AddLogFile("abc-123-logging-errors.txt",
@"2014-01-09T00:18:30
System.ApplicationException: The trace listener AzureTableTraceListener is disabled.
at Microsoft.WindowsAzure.WebSites.Diagnostics.AzureTableTraceListener.GetCloudTableClientFromEnvironment()
at Microsoft.WindowsAzure.WebSites.Diagnostics.AzureTableTraceListener.RefreshConfig()
--- End of inner exception stack trace ---"
);
dir.AddLogFile("log-4.txt",
@"2013-12-06T00:29:23 PID[20108] Information this is a log
2013-12-06T00:29:24 PID[20108] Information this is a log
2013-12-06T00:29:25 PID[20108] Information this is a log
2013-12-06T00:29:26 PID[20108] Information this is a log
2013-12-06T00:29:27 PID[20108] Information this is a log
2013-12-06T00:29:28 PID[20108] Information this is a log
2013-12-06T00:29:29 PID[20108] Warning this is a warning
2013-12-06T00:29:30 PID[20108] Error this is an error"
);
var env = new ApplicationLogsTestEnvironment(dir.RootDir);
var reader = new ApplicationLogsReader(env, Mock.Of <ITracer>());
var loopResult = Parallel.For(0, 10, (i) =>
{
var results = reader.GetRecentLogs(20).ToList();
Assert.Equal(14, results.Count);
});
Assert.True(loopResult.IsCompleted);
}
}
public void ResumableLogReaderDoesNotBlockLogWriters()
{
var fs = new FileSystem();
FileSystemHelpers.Instance = fs;
using (var dir = new TemporaryApplicationLogDirectory(fs))
{
var logFile = dir.AddLogFile("log-1.txt",
@"2013-12-06T00:29:20 PID[20108] Information this is a log
2013-12-06T00:29:21 PID[20108] Warning this is a warning
");
// Open a reader and read the lines while the writer appends a new line
using (var reader = new ApplicationLogsReader.ResumableLogFileReader(logFile, Mock.Of <ITracer>()))
{
var results = reader.ReadNextBatch(1);
Assert.Equal(1, results.Count);
results[0].AssertLogEntry("2013-12-06T00:29:21+00:00", "Warning", "this is a warning");
using (var writer = new StreamWriter(fs.File.Open(logFile.FullName, FileMode.Append, FileAccess.Write, FileShare.ReadWrite)))
{
writer.WriteLine("2013-12-06T00:29:22 PID[20108] Error this is an error");
}
results = reader.ReadNextBatch(1);
Assert.Equal(1, results.Count);
results[0].AssertLogEntry("2013-12-06T00:29:20+00:00", "Information", "this is a log");
}
// Open a new reader and confirm that the new line written by the writer is present
using (var reader = new ApplicationLogsReader.ResumableLogFileReader(logFile, Mock.Of <ITracer>()))
{
var results = reader.ReadNextBatch(1);
Assert.Equal(1, results.Count);
results[0].AssertLogEntry("2013-12-06T00:29:22+00:00", "Error", "this is an error");
}
}
}