public async void MultipleLogEntriesAreWrittenToTheTargetLogFile()
{
var serializer = new XmlSerializerSerializer();
var logProvider = CreateLogProvider(serializer, _logFilePath);
var logEntry0 = new LogEntry("Hello, world!", new { Foo = "bar" });
await logProvider.WriteAsync(logEntry0);
var logEntry1 = new LogEntry("Good-bye, cruel world!", new { Omg = "wtf" });
await logProvider.WriteAsync(logEntry1);
var logEntry2 = new LogEntry("Awkward message, trying to compete with the other two", new { Sad = "panda" });
await logProvider.WriteAsync(logEntry2);
var logFileContents = File.ReadAllText(_logFilePath);
var xmlDocuments =
logFileContents.Split(
new[] { _xmlDeclaration },
StringSplitOptions.RemoveEmptyEntries);
Assert.That(xmlDocuments.Length, Is.EqualTo(3));
var deserializedLogEntry0 = serializer.DeserializeFromString<LogEntry>(xmlDocuments[0]);
Assert.That(_equalityComparer.Equals(logEntry0, deserializedLogEntry0), Is.True);
var deserializedLogEntry1 = serializer.DeserializeFromString<LogEntry>(xmlDocuments[1]);
Assert.That(_equalityComparer.Equals(logEntry1, deserializedLogEntry1), Is.True);
var deserializedLogEntry2 = serializer.DeserializeFromString<LogEntry>(xmlDocuments[2]);
Assert.That(_equalityComparer.Equals(logEntry2, deserializedLogEntry2), Is.True);
}
public async void ASingleLogEntryIsWrittenToTheTargetLogFile()
{
var serializer = new XmlSerializerSerializer();
var logProvider = CreateLogProvider(serializer, _logFilePath);
var logEntry = new LogEntry("Hello, world!", new { Foo = "bar" });
await logProvider.WriteAsync(logEntry);
var logFileContents = File.ReadAllText(_logFilePath);
var xmlDocuments =
logFileContents.Split(
new[] { _xmlDeclaration },
StringSplitOptions.RemoveEmptyEntries);
Assert.That(xmlDocuments.Length, Is.EqualTo(1));
var deserializedLogEntry = serializer.DeserializeFromString<LogEntry>(xmlDocuments[0]);
Assert.That(_equalityComparer.Equals(logEntry, deserializedLogEntry), Is.True);
}
public async void IsThreadSafe()
{
const int tasksPerProcessor = 5;
const int logEntriesPerTask = 5;
var serializer = new XmlSerializerSerializer();
var logProvider = CreateLogProvider(serializer, _logFilePath);
var tasks = new Task[Environment.ProcessorCount * tasksPerProcessor];
var logEntry = new LogEntry("Hello, world!", new { Foo = "bar" });
Func<Task> getWriteLogEntriesTask =
async () =>
{
for (var i = 0; i < logEntriesPerTask; i++)
{
await logProvider.WriteAsync(logEntry);
}
};
for (int i = 0; i < tasks.Length; i++)
{
tasks[i] = getWriteLogEntriesTask();
}
await Task.WhenAll(tasks);
var logFileContents = File.ReadAllText(_logFilePath);
var xmlDocuments =
logFileContents.Split(
new[] { _xmlDeclaration + Environment.NewLine },
StringSplitOptions.RemoveEmptyEntries);
// We are reasonably certain that we are thread-safe because we didn't lose
// any log entries (also because we didn't throw an exception).
Assert.That(xmlDocuments.Length, Is.EqualTo(Environment.ProcessorCount * logEntriesPerTask * tasksPerProcessor));
}
public async void AnExistingFileIsAppended()
{
File.WriteAllLines(_logFilePath, new[] { _xmlDeclaration });
var fileInfo = new FileInfo(_logFilePath);
Assert.That(fileInfo.Length, Is.EqualTo(_xmlDeclaration.Length + Environment.NewLine.Length));
var serializer = new XmlSerializerSerializer();
var logProvider = CreateLogProvider(serializer, _logFilePath);
var logEntry = new LogEntry("Hello, world!", new { Foo = "bar" });
await logProvider.WriteAsync(logEntry);
var logFileContents = File.ReadAllText(_logFilePath);
var xmlDocuments =
logFileContents.Split(
new[] { _xmlDeclaration + Environment.NewLine },
StringSplitOptions.RemoveEmptyEntries);
Assert.That(xmlDocuments.Length, Is.EqualTo(1));
var deserializedLogEntry = serializer.DeserializeFromString<LogEntry>(xmlDocuments[0]);
Assert.That(_equalityComparer.Equals(logEntry, deserializedLogEntry), Is.True);
var serializedLogEntry = serializer.SerializeToString(logEntry);
Assert.That(logFileContents.Length, Is.EqualTo(_xmlDeclaration.Length + Environment.NewLine.Length + serializedLogEntry.Length + Environment.NewLine.Length));
}