/// <summary>
/// Reads a log message from the specified sqlite reader.
/// </summary>
/// <param name="reader">Sqlite reader to read from.</param>
/// <returns>The read log message (is protected).</returns>
private LogFileMessage ReadLogMessage(SQLiteDataReader reader)
{
// columns in result:
// 0 = message id
// 1 = timestamp
// 2 = timezone offset
// 3 = high precision timestamp
// 4 = lost message count
// 5 = process id
// 6 = process name
// 7 = application name
// 8 = log writer name
// 9 = log level name
// 10 = has tags
// 11 = text name
long messageId = reader.GetInt64(0);
var timezoneOffset = TimeSpan.FromTicks(reader.GetInt64(2));
var timestamp = new DateTimeOffset(reader.GetInt64(1) + timezoneOffset.Ticks, timezoneOffset);
long highPrecisionTimestamp = reader.GetInt64(3);
int lostMessageCount = reader.GetInt32(4);
int processId = reader.GetInt32(5);
string processName = reader.GetString(6);
string applicationName = reader.GetString(7);
string logWriterName = reader.GetString(8);
string logLevelName = reader.GetString(9);
bool hasTags = reader.GetBoolean(10);
string text = reader.GetString(11);
var message = new LogFileMessage().InitWith(
messageId,
timestamp,
highPrecisionTimestamp,
lostMessageCount,
StringPool.Intern(logWriterName),
StringPool.Intern(logLevelName),
TagSet.Empty,
StringPool.Intern(applicationName),
StringPool.Intern(processName),
processId,
text);
// initialize tags, if there are tags associated with the message
if (hasTags)
{
message.Tags = GetTagsOfMessage(messageId);
}
// protect message from changes
message.Protect();
return(message);
}
/// <summary>
/// Tests setting a property of the <see cref="LogFileMessage"/> class.
/// </summary>
/// <param name="property">Property to test.</param>
/// <param name="expectedDefaultValue">Expected default value of the property.</param>
/// <param name="valueToSet">Value of the property after setting it.</param>
/// <param name="protect">true to protect the log message before setting the property; otherwise false.</param>
private static void TestPropertySetter_WithoutPropertyChanged(
Expression <Func <LogFileMessage, object> > property,
object expectedDefaultValue,
object valueToSet,
bool protect)
{
var message = new LogFileMessage();
// extract information about the property to work with
PropertyInfo propertyInfo;
switch (property.Body.NodeType)
{
case ExpressionType.MemberAccess:
propertyInfo = (PropertyInfo)((MemberExpression)property.Body).Member;
break;
case ExpressionType.Convert:
propertyInfo = (PropertyInfo)((MemberExpression)((UnaryExpression)property.Body).Operand).Member;
break;
default:
throw new NotImplementedException();
}
object value = propertyInfo.GetValue(message);
Assert.Equal(expectedDefaultValue, value);
if (protect)
{
message.Protect();
var ex = Assert.Throws <TargetInvocationException>(() => propertyInfo.SetValue(message, valueToSet, null));
Assert.IsType <NotSupportedException>(ex.InnerException);
value = propertyInfo.GetValue(message);
Assert.Equal(expectedDefaultValue, value);
}
else
{
propertyInfo.SetValue(message, valueToSet, null);
value = propertyInfo.GetValue(message);
if (propertyInfo.PropertyType.IsValueType)
{
Assert.Equal(valueToSet, value);
}
else
{
Assert.Same(valueToSet, value);
}
}
}
private async Task Protect(bool protectInSameThread, bool withPropertyChanged)
{
// create a new message
var message = new LogFileMessage();
Assert.False(message.IsReadOnly);
CheckDefaultState(message, true, false);
// ensure that the message is not marked for asynchronous initialization
Assert.False(message.IsAsyncInitPending);
// prepare data pulling some information out of the event handler
SynchronizationContext handlerThreadSynchronizationContext = null;
var changedPropertyNames = new List <string>();
var handlerCalledEvent = new ManualResetEventSlim(false);
// the handler that is expected to be called on changes
void PropertyChangedHandler(object sender, PropertyChangedEventArgs e)
{
handlerThreadSynchronizationContext = SynchronizationContext.Current;
changedPropertyNames.Add(e.PropertyName);
handlerCalledEvent.Set();
}
// run test in a separate thread that provides a synchronization context that allows to
// marshal calls into that thread
await mThread.Factory.Run(() => { Assert.NotNull(SynchronizationContext.Current); });
// register the PropertyChanged event
if (withPropertyChanged)
{
await mThread.Factory.Run(() => { message.PropertyChanged += PropertyChangedHandler; });
}
// callback that initializes the message
void ProtectTest()
{
// protect the message
message.Protect();
// check administrative properties
Assert.True(message.IsInitialized); // unchanged
Assert.False(message.IsAsyncInitPending); // unchanged
Assert.True(message.IsReadOnly);
if (protectInSameThread)
{
if (withPropertyChanged)
{
// the event handler should have been called only once in the same thread
// (the event handler is called directly as the registering thread is the same as the thread raising the event)
Assert.True(handlerCalledEvent.IsSet);
Assert.Equal(new[] { "IsReadOnly" }, changedPropertyNames.ToArray());
}
else
{
// the event handler should not have been called
Assert.False(handlerCalledEvent.IsSet);
}
}
}
// protect the message either in the context of the thread that registered the handler
// or in a different - the current - thread
if (protectInSameThread)
{
await mThread.Factory.Run(ProtectTest);
}
else
{
ProtectTest();
}
if (!protectInSameThread)
{
// the thread registering the event and the thread protecting the message are different
if (withPropertyChanged)
{
// event handler should run in the context of the thread that registered it
Assert.True(handlerCalledEvent.Wait(1000));
Assert.Same(mThread.Context.SynchronizationContext, handlerThreadSynchronizationContext);
Assert.Equal(new[] { "IsReadOnly" }, changedPropertyNames.ToArray());
}
else
{
// the event handler should not have been called
Assert.False(handlerCalledEvent.Wait(1000));
}
}
}
/// <summary>
/// Tests setting a property of the <see cref="LogFileMessage"/> class.
/// </summary>
/// <param name="property">Property to test.</param>
/// <param name="expectedDefaultValue">Expected default value of the property.</param>
/// <param name="valueToSet">Value of the property after setting it.</param>
/// <param name="protect">true to protect the log message before setting the property; otherwise false.</param>
/// <param name="changeInSameThread">
/// true to change the property in the thread that registers the event;
/// false to change the property and raise the event in some other thread.
/// </param>
private async Task TestPropertySetter_WithPropertyChanged(
Expression <Func <LogFileMessage, object> > property,
object expectedDefaultValue,
object valueToSet,
bool protect,
bool changeInSameThread)
{
var message = new LogFileMessage();
// extract information about the property to work with
PropertyInfo propertyInfo;
switch (property.Body.NodeType)
{
case ExpressionType.MemberAccess:
propertyInfo = (PropertyInfo)((MemberExpression)property.Body).Member;
break;
case ExpressionType.Convert:
propertyInfo = (PropertyInfo)((MemberExpression)((UnaryExpression)property.Body).Operand).Member;
break;
default:
throw new NotImplementedException();
}
// check default value of the property
object value = propertyInfo.GetValue(message);
Assert.Equal(expectedDefaultValue, value);
// prepare data pulling some information out of the event handler
SynchronizationContext handlerThreadSynchronizationContext = null;
var changedPropertyNames = new List <string>();
var handlerCalledEvent = new ManualResetEventSlim(false);
// the handler that is expected to be called on changes
void PropertyChangedHandler(object sender, PropertyChangedEventArgs e)
{
handlerThreadSynchronizationContext = SynchronizationContext.Current;
changedPropertyNames.Add(e.PropertyName);
handlerCalledEvent.Set();
}
// run test in a separate thread that provides a synchronization context that allows to
// marshal calls into that thread
await mThread.Factory.Run(() => { Assert.NotNull(SynchronizationContext.Current); });
// register the PropertyChanged event
await mThread.Factory.Run(() => { message.PropertyChanged += PropertyChangedHandler; });
// set property
if (changeInSameThread)
{
// registering the event and changing the property is done in the same thread
// => the event handler should be called directly
await mThread.Factory.Run(
() =>
{
if (protect)
{
// protect the message
// => changes the IsReadOnly property to true
// => event handler is called directly
message.Protect();
Assert.True(handlerCalledEvent.IsSet, "The event handler should have been called directly.");
Assert.Same(SynchronizationContext.Current, handlerThreadSynchronizationContext);
Assert.Equal(new[] { "IsReadOnly" }, changedPropertyNames.ToArray());
handlerCalledEvent.Reset();
// the message is protected and setting a property should throw an exception
var ex = Assert.Throws <TargetInvocationException>(() => propertyInfo.SetValue(message, valueToSet, null));
Assert.IsType <NotSupportedException>(ex.InnerException);
// the property value should not have changed
value = propertyInfo.GetValue(message);
Assert.Equal(expectedDefaultValue, value);
// the event handler should not have been called directly
Assert.False(handlerCalledEvent.IsSet);
}
else
{
// set property
propertyInfo.SetValue(message, valueToSet, null);
// the property value should not be the same as the set value
value = propertyInfo.GetValue(message);
if (propertyInfo.PropertyType.IsValueType)
{
Assert.Equal(valueToSet, value);
}
else
{
Assert.Same(valueToSet, value);
}
// the event handler should have been called directly
Assert.True(handlerCalledEvent.IsSet);
Assert.Same(SynchronizationContext.Current, handlerThreadSynchronizationContext);
Assert.Equal(new[] { propertyInfo.Name }, changedPropertyNames.ToArray());
}
});
}
else
{
// the thread registering the event is different from the thread changing the property and raising the event
// => the event handler should be scheduled to run on the thread that has registered the event
if (protect)
{
// protect the message
// => changes the IsReadOnly property to true
// => event handler should have been scheduled to run
message.Protect();
Assert.True(handlerCalledEvent.Wait(1000));
Assert.Same(mThread.Context.SynchronizationContext, handlerThreadSynchronizationContext);
Assert.Equal(new[] { "IsReadOnly" }, changedPropertyNames.ToArray());
handlerCalledEvent.Reset();
// the message is protected and setting a property should throw an exception
var ex = Assert.Throws <TargetInvocationException>(() => propertyInfo.SetValue(message, valueToSet, null));
Assert.IsType <NotSupportedException>(ex.InnerException);
// the property value should not have changed
value = propertyInfo.GetValue(message);
Assert.Equal(expectedDefaultValue, value);
// the event handler should neither have been called directly nor should it be scheduled to run
Assert.False(handlerCalledEvent.Wait(1000));
}
else
{
// set property
propertyInfo.SetValue(message, valueToSet, null);
// the property value should not be the same as the set value
value = propertyInfo.GetValue(message);
if (propertyInfo.PropertyType.IsValueType)
{
Assert.Equal(valueToSet, value);
}
else
{
Assert.Same(valueToSet, value);
}
// the event handler should run in the context of the thread that registered the event
Assert.True(handlerCalledEvent.Wait(1000));
Assert.Same(mThread.Context.SynchronizationContext, handlerThreadSynchronizationContext);
Assert.Equal(new[] { propertyInfo.Name }, changedPropertyNames.ToArray());
}
}
// unregister the PropertyChanged event
await mThread.Factory.Run(() => { message.PropertyChanged -= PropertyChangedHandler; });
}
