/// <summary>
/// Serializes an object to a string.
/// </summary>
/// <param name="value">The object to serialize.</param>
/// <param name="context">The context of the serialization.</param>
/// <returns>The serialized representation of the object.</returns>
public override string SerializeObject(object value, TraceSerializationContext context)
{
if (value == null)
return null;
return value.ToString();
}
/// <summary>
/// Serializes an object to a string.
/// </summary>
/// <param name="value">The object to serialize.</param>
/// <param name="context">The context of the serialization.</param>
/// <returns>The serialized representation of the object.</returns>
public override string SerializeObject(object value, TraceSerializationContext context)
{
if (value == null)
{
return(null);
}
return(value.ToString());
}
/// <summary>
/// Called by EventSourceProxy to serialize an object. This method should call ShouldSerialize
/// then SerializeObject if serialization is enabled.
/// </summary>
/// <param name="value">The value to serialize.</param>
/// <param name="context">The serialization context.</param>
/// <returns>The serialized value.</returns>
public virtual string ProvideSerialization(object value, TraceSerializationContext context)
{
if (!ShouldSerialize(context))
{
return(null);
}
return(SerializeObject(value, context));
}
public override string SerializeObject(object value, TraceSerializationContext context)
{
try
{
// if we have a task, don't attempt to serialize the task if it's not completed
Task t = value as Task;
if (t != null && !t.IsCompleted)
{
return JsonConvert.SerializeObject(new { TaskId = t.Id });
}
return JsonConvert.SerializeObject(value);
}
catch (Exception e)
{
// don't let serialization exceptions blow up processing
return String.Format(CultureInfo.InvariantCulture, "{{ Exception: '{0}' }}", e.Message.Replace("'", "\\'"));
}
}
public override string SerializeObject(object value, TraceSerializationContext context)
{
try
{
// if we have a task, don't attempt to serialize the task if it's not completed
Task t = value as Task;
if (t != null && !t.IsCompleted)
{
return(JsonConvert.SerializeObject(new { TaskId = t.Id }));
}
return(JsonConvert.SerializeObject(value));
}
catch (Exception e)
{
// don't let serialization exceptions blow up processing
return(String.Format(CultureInfo.InvariantCulture, "{{ Exception: '{0}' }}", e.Message.Replace("'", "\\'")));
}
}
/// <summary>
/// Returns the EventLevel at which to enable serialization for the given context.
/// This method looks at the TraceSerializationAttributes on the parameter, method, or class.
/// </summary>
/// <param name="context">The serialization context to evaluate.</param>
/// <returns>The EventLevel at which to enable serialization for the given context.</returns>
public virtual EventLevel? GetEventLevelForContext(TraceSerializationContext context)
{
if (context == null) throw new ArgumentNullException("context");
TraceSerializationAttribute attribute = null;
// look on the parameter first
ParameterInfo parameterInfo = null;
switch (context.ContextType)
{
case InvocationContextTypes.MethodCall:
parameterInfo = context.MethodInfo.GetParameters()[context.ParameterIndex];
break;
case InvocationContextTypes.MethodCompletion:
parameterInfo = context.MethodInfo.ReturnParameter;
break;
}
if (parameterInfo != null)
{
// look at the attribute on the parameter
attribute = parameterInfo.GetCustomAttribute<TraceSerializationAttribute>();
if (attribute != null)
return attribute.Level;
// look at the attribute on the parameter's type
attribute = parameterInfo.ParameterType.GetCustomAttribute<TraceSerializationAttribute>();
if (attribute != null)
return attribute.Level;
}
// now look on the method
attribute = context.MethodInfo.GetCustomAttribute<TraceSerializationAttribute>();
if (attribute != null)
return attribute.Level;
// now look at the type
attribute = context.MethodInfo.DeclaringType.GetCustomAttribute<TraceSerializationAttribute>();
if (attribute != null)
return attribute.Level;
return _defaultEventLevel;
}
/// <summary>
/// Returns if the should the given parameter be serialized.
/// </summary>
/// <param name="context">The context of the serialization.</param>
/// <returns>True if the value should be serialized, false otherwise.</returns>
public virtual bool ShouldSerialize(TraceSerializationContext context)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
if (context.EventLevel == null)
{
return(false);
}
var eventLevel = context.EventLevel.Value;
if (eventLevel == EventLevel.LogAlways)
{
return(true);
}
return(context.EventSource.IsEnabled(eventLevel, (EventKeywords)(-1)));
}
/// <summary> /// Serializes an object to a string. /// </summary> /// <param name="value">The object to serialize.</param> /// <param name="context">The context of the serialization.</param> /// <returns>The serialized representation of the object.</returns> public abstract string SerializeObject(object value, TraceSerializationContext context);
/// <summary>
/// Returns if the should the given parameter be serialized.
/// </summary>
/// <param name="context">The context of the serialization.</param>
/// <returns>True if the value should be serialized, false otherwise.</returns>
public override bool ShouldSerialize(TraceSerializationContext context)
{
return(false);
}
/// <summary>
/// Called by EventSourceProxy to serialize an object. This method should call ShouldSerialize
/// then SerializeObject if serialization is enabled.
/// </summary>
/// <param name="value">The value to serialize.</param>
/// <param name="context">The serialization context.</param>
/// <returns>The serialized value.</returns>
public virtual string ProvideSerialization(object value, TraceSerializationContext context)
{
if (!ShouldSerialize(context))
return null;
return SerializeObject(value, context);
}
/// <summary>
/// Returns the EventLevel at which to enable serialization for the given context.
/// This method looks at the TraceSerializationAttributes on the parameter, method, or class.
/// </summary>
/// <param name="context">The serialization context to evaluate.</param>
/// <returns>The EventLevel at which to enable serialization for the given context.</returns>
public override EventLevel?GetEventLevelForContext(TraceSerializationContext context)
{
return(null);
}
/// <summary>
/// Serializes an object to a string.
/// </summary>
/// <param name="value">The object to serialize.</param>
/// <param name="context">The context of the serialization.</param>
/// <returns>The serialized representation of the object.</returns>
public override string SerializeObject(object value, TraceSerializationContext context)
{
return(null);
}
/// <summary>
/// Returns if the should the given parameter be serialized.
/// </summary>
/// <param name="context">The context of the serialization.</param>
/// <returns>True if the value should be serialized, false otherwise.</returns>
public override bool ShouldSerialize(TraceSerializationContext context)
{
return false;
}
/// <summary>
/// Serializes an object to a string.
/// </summary>
/// <param name="value">The object to serialize.</param>
/// <param name="context">The context of the serialization.</param>
/// <returns>The serialized representation of the object.</returns>
public override string SerializeObject(object value, TraceSerializationContext context)
{
return null;
}
/// <summary>
/// Emits the code needed to properly push an object on the stack,
/// serializing the value if necessary.
/// </summary>
/// <param name="typeBuilder">The TypeBuilder for the method being built.</param>
/// <param name="methodBuilder">The method currently being built.</param>
/// <param name="invocationContext">The invocation context for this call.</param>
/// <param name="invocationContexts">A list of invocation contexts that will be appended to.</param>
/// <param name="invocationContextsField">The static field containing the array of invocation contexts at runtime.</param>
/// <param name="parameterMapping">The mapping of source parameters to destination parameters.</param>
/// <param name="serializationProvider">The serialization provider for the current interface.</param>
/// <param name="serializationProviderField">
/// The field on the current object that contains the serialization provider at runtime.
/// This method assume the current object is stored in arg.0.
/// </param>
internal static void EmitSerializeValue(
TypeBuilder typeBuilder,
MethodBuilder methodBuilder,
InvocationContext invocationContext,
List<InvocationContext> invocationContexts,
FieldBuilder invocationContextsField,
ParameterMapping parameterMapping,
TraceSerializationProvider serializationProvider,
FieldBuilder serializationProviderField)
{
var sourceCount = parameterMapping.Sources.Count();
if (sourceCount == 0)
return;
if (sourceCount == 1)
{
var parameter = parameterMapping.Sources.First();
EmitSerializeValue(
typeBuilder,
methodBuilder,
invocationContext,
invocationContexts,
invocationContextsField,
parameter.Position,
parameter.SourceType,
parameterMapping.CleanTargetType,
parameter.Converter,
serializationProvider,
serializationProviderField);
return;
}
var il = methodBuilder.GetILGenerator();
// use the serializer to serialize the objects
var context = new TraceSerializationContext(invocationContext.SpecifyType(InvocationContextTypes.BundleParameters), -1);
context.EventLevel = serializationProvider.GetEventLevelForContext(context);
if (context.EventLevel != null)
{
// get the object serializer from the this pointer
il.Emit(OpCodes.Ldsfld, serializationProviderField);
// create a new dictionary strings and values
il.Emit(OpCodes.Newobj, typeof(Dictionary<string, string>).GetConstructor(Type.EmptyTypes));
foreach (var parameter in parameterMapping.Sources)
{
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Ldstr, parameter.Alias);
EmitSerializeValue(
typeBuilder,
methodBuilder,
invocationContext,
invocationContexts,
invocationContextsField,
parameter.Position,
parameter.SourceType,
parameterMapping.CleanTargetType,
parameter.Converter,
serializationProvider,
serializationProviderField);
var method = typeof(Dictionary<string, string>).GetMethod("Add");
il.Emit(OpCodes.Call, method);
}
// get the invocation context from the array on the provider
il.Emit(OpCodes.Ldsfld, invocationContextsField);
il.Emit(OpCodes.Ldc_I4, invocationContexts.Count);
il.Emit(OpCodes.Ldelem, typeof(TraceSerializationContext));
invocationContexts.Add(context);
il.Emit(OpCodes.Callvirt, typeof(TraceSerializationProvider).GetMethod("ProvideSerialization", BindingFlags.Instance | BindingFlags.Public));
}
else
il.Emit(OpCodes.Ldnull);
}
/// <summary>
/// Returns if the should the given parameter be serialized.
/// </summary>
/// <param name="context">The context of the serialization.</param>
/// <returns>True if the value should be serialized, false otherwise.</returns>
public virtual bool ShouldSerialize(TraceSerializationContext context)
{
if (context == null) throw new ArgumentNullException("context");
if (context.EventLevel == null)
return false;
var eventLevel = context.EventLevel.Value;
if (eventLevel == EventLevel.LogAlways)
return true;
return context.EventSource.IsEnabled(eventLevel, (EventKeywords)(-1));
}
/// <summary>
/// Emits the code needed to properly push an object on the stack,
/// serializing the value if necessary.
/// </summary>
/// <param name="methodBuilder">The method currently being built.</param>
/// <param name="invocationContext">The invocation context for this call.</param>
/// <param name="invocationContexts">A list of invocation contexts that will be appended to.</param>
/// <param name="invocationContextsField">The static field containing the array of invocation contexts at runtime.</param>
/// <param name="i">The index of the current parameter being pushed.</param>
/// <param name="sourceType">The type that the parameter is being converted from.</param>
/// <param name="targetType">The type that the parameter is being converted to.</param>
/// <param name="serializationProvider">The serialization provider for the current interface.</param>
/// <param name="serializationProviderField">
/// The field on the current object that contains the serialization provider at runtime.
/// This method assume the current object is stored in arg.0.
/// </param>
internal static void EmitSerializeValue(
MethodBuilder methodBuilder,
InvocationContext invocationContext,
List<InvocationContext> invocationContexts,
FieldBuilder invocationContextsField,
int i,
Type sourceType,
Type targetType,
TraceSerializationProvider serializationProvider,
FieldBuilder serializationProviderField)
{
ILGenerator mIL = methodBuilder.GetILGenerator();
// if the source type is a reference to the target type, we have to dereference it
if (sourceType.IsByRef && sourceType.GetElementType() == targetType)
{
mIL.Emit(OpCodes.Ldarg, (int)i + 1);
sourceType = sourceType.GetElementType();
mIL.Emit(OpCodes.Ldobj, sourceType);
return;
}
// if the types match, just put the argument on the stack
if (sourceType == targetType)
{
mIL.Emit(OpCodes.Ldarg, (int)i + 1);
return;
}
// this is not a match, so convert using the serializer.
// verify that the target type is a string
if (targetType != typeof(string))
throw new InvalidOperationException(String.Format(CultureInfo.InvariantCulture, "Cannot convert type {0} to a type compatible with EventSource", targetType.FullName));
// for fundamental types, just convert them with ToString and be done with it
var underlyingType = Nullable.GetUnderlyingType(sourceType) ?? sourceType;
if (!sourceType.IsGenericParameter && (underlyingType.IsEnum || (underlyingType.IsValueType && underlyingType.Assembly == typeof(string).Assembly)))
{
// convert the argument to a string with ToString
mIL.Emit(OpCodes.Ldarga_S, i + 1);
mIL.Emit(OpCodes.Call, sourceType.GetMethod("ToString", Type.EmptyTypes));
return;
}
// non-fundamental types use the object serializer
var context = new TraceSerializationContext(invocationContext, i);
context.EventLevel = serializationProvider.GetEventLevelForContext(context);
if (context.EventLevel != null)
{
// get the object serializer from the this pointer
mIL.Emit(OpCodes.Ldsfld, serializationProviderField);
// load the value
mIL.Emit(OpCodes.Ldarg, (int)i + 1);
// if the source type is a reference to the target type, we have to dereference it
if (sourceType.IsByRef)
{
sourceType = sourceType.GetElementType();
mIL.Emit(OpCodes.Ldobj, sourceType);
}
// if it's a value type, we have to box it to log it
if (sourceType.IsGenericParameter || sourceType.IsValueType)
mIL.Emit(OpCodes.Box, sourceType);
// get the invocation context from the array on the provider
mIL.Emit(OpCodes.Ldsfld, invocationContextsField);
mIL.Emit(OpCodes.Ldc_I4, invocationContexts.Count);
mIL.Emit(OpCodes.Ldelem, typeof(TraceSerializationContext));
invocationContexts.Add(context);
mIL.Emit(OpCodes.Callvirt, typeof(TraceSerializationProvider).GetMethod("ProvideSerialization", BindingFlags.Instance | BindingFlags.Public));
}
else
mIL.Emit(OpCodes.Ldnull);
}
/// <summary> /// Serializes an object to a string. /// </summary> /// <param name="value">The object to serialize.</param> /// <param name="context">The context of the serialization.</param> /// <returns>The serialized representation of the object.</returns> public abstract string SerializeObject(object value, TraceSerializationContext context);
/// <summary>
/// Returns the EventLevel at which to enable serialization for the given context.
/// This method looks at the TraceSerializationAttributes on the parameter, method, or class.
/// </summary>
/// <param name="context">The serialization context to evaluate.</param>
/// <returns>The EventLevel at which to enable serialization for the given context.</returns>
public virtual EventLevel?GetEventLevelForContext(TraceSerializationContext context)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
TraceSerializationAttribute attribute = null;
// look on the parameter first
ParameterInfo parameterInfo = null;
switch (context.ContextType)
{
case InvocationContextTypes.MethodCall:
// added context data is added by default
if (context.ParameterIndex < 0)
{
return(_defaultEventLevel);
}
parameterInfo = context.MethodInfo.GetParameters()[context.ParameterIndex];
break;
case InvocationContextTypes.MethodCompletion:
parameterInfo = context.MethodInfo.ReturnParameter;
break;
}
if (parameterInfo != null)
{
// look at the attribute on the parameter
attribute = parameterInfo.GetCustomAttribute <TraceSerializationAttribute>();
if (attribute != null)
{
return(attribute.Level);
}
// look at the attribute on the parameter's type
attribute = parameterInfo.ParameterType.GetCustomAttribute <TraceSerializationAttribute>();
if (attribute != null)
{
return(attribute.Level);
}
}
// now look on the method
attribute = context.MethodInfo.GetCustomAttribute <TraceSerializationAttribute>();
if (attribute != null)
{
return(attribute.Level);
}
// now look at the type
attribute = context.MethodInfo.DeclaringType.GetCustomAttribute <TraceSerializationAttribute>();
if (attribute != null)
{
return(attribute.Level);
}
return(_defaultEventLevel);
}
/// <summary>
/// Emits the code needed to properly push an object on the stack,
/// serializing the value if necessary.
/// </summary>
/// <param name="typeBuilder">The TypeBuilder for the method being built.</param>
/// <param name="methodBuilder">The method currently being built.</param>
/// <param name="invocationContext">The invocation context for this call.</param>
/// <param name="invocationContexts">A list of invocation contexts that will be appended to.</param>
/// <param name="invocationContextsField">The static field containing the array of invocation contexts at runtime.</param>
/// <param name="i">The index of the current parameter being pushed.</param>
/// <param name="sourceType">The type that the parameter is being converted from.</param>
/// <param name="targetType">The type that the parameter is being converted to.</param>
/// <param name="converter">An optional converter to apply to the source type.</param>
/// <param name="serializationProvider">The serialization provider for the current interface.</param>
/// <param name="serializationProviderField">
/// The field on the current object that contains the serialization provider at runtime.
/// This method assume the current object is stored in arg.0.
/// </param>
internal static void EmitSerializeValue(
TypeBuilder typeBuilder,
MethodBuilder methodBuilder,
InvocationContext invocationContext,
List<InvocationContext> invocationContexts,
FieldBuilder invocationContextsField,
int i,
Type sourceType,
Type targetType,
LambdaExpression converter,
TraceSerializationProvider serializationProvider,
FieldBuilder serializationProviderField)
{
ILGenerator mIL = methodBuilder.GetILGenerator();
// if the source is a parameter, then load the parameter onto the stack
if (i >= 0)
mIL.Emit(OpCodes.Ldarg, i + 1);
// if a converter is passed in, then define a static method and use it to convert
if (converter != null)
{
MethodBuilder mb = typeBuilder.DefineMethod(Guid.NewGuid().ToString(), MethodAttributes.Static | MethodAttributes.Public, converter.ReturnType, converter.Parameters.Select(p => p.Type).ToArray());
converter.CompileToMethod(mb);
mIL.Emit(OpCodes.Call, mb);
// the object on the stack is now the return type. we may need to convert it further
sourceType = converter.ReturnType;
}
// if the source type is a reference to the target type, we have to dereference it
if (sourceType.IsByRef && sourceType.GetElementType() == targetType)
{
sourceType = sourceType.GetElementType();
mIL.Emit(OpCodes.Ldobj, sourceType);
return;
}
// if the types match, just put the argument on the stack
if (sourceType == targetType)
return;
// this is not a match, so convert using the serializer.
// verify that the target type is a string
if (targetType != typeof(string))
throw new InvalidOperationException(String.Format(CultureInfo.InvariantCulture, "Cannot convert type {0} to a type compatible with EventSource", targetType.FullName));
// for fundamental types, just convert them with ToString and be done with it
var underlyingType = Nullable.GetUnderlyingType(sourceType) ?? sourceType;
if (!sourceType.IsGenericParameter && (underlyingType.IsEnum || (underlyingType.IsValueType && underlyingType.Assembly == typeof(string).Assembly)))
{
// convert the argument to a string with ToString
LocalBuilder lb = mIL.DeclareLocal(sourceType);
mIL.Emit(OpCodes.Stloc, lb.LocalIndex);
mIL.Emit(OpCodes.Ldloca, lb.LocalIndex);
mIL.Emit(OpCodes.Call, sourceType.GetMethod("ToString", Type.EmptyTypes));
return;
}
// non-fundamental types use the object serializer
var context = new TraceSerializationContext(invocationContext, i);
context.EventLevel = serializationProvider.GetEventLevelForContext(context);
if (context.EventLevel != null)
{
LocalBuilder lb = mIL.DeclareLocal(sourceType);
mIL.Emit(OpCodes.Stloc, lb.LocalIndex);
// get the object serializer from the this pointer
mIL.Emit(OpCodes.Ldsfld, serializationProviderField);
mIL.Emit(OpCodes.Ldloc, lb.LocalIndex);
// if the source type is a reference to the target type, we have to dereference it
if (sourceType.IsByRef)
{
sourceType = sourceType.GetElementType();
mIL.Emit(OpCodes.Ldobj, sourceType);
}
// if it's a value type, we have to box it to log it
if (sourceType.IsGenericParameter || sourceType.IsValueType)
mIL.Emit(OpCodes.Box, sourceType);
// get the invocation context from the array on the provider
mIL.Emit(OpCodes.Ldsfld, invocationContextsField);
mIL.Emit(OpCodes.Ldc_I4, invocationContexts.Count);
mIL.Emit(OpCodes.Ldelem, typeof(TraceSerializationContext));
invocationContexts.Add(context);
mIL.Emit(OpCodes.Callvirt, typeof(TraceSerializationProvider).GetMethod("ProvideSerialization", BindingFlags.Instance | BindingFlags.Public));
}
else
{
mIL.Emit(OpCodes.Pop);
mIL.Emit(OpCodes.Ldnull);
}
}
/// <summary>
/// Returns the EventLevel at which to enable serialization for the given context.
/// This method looks at the TraceSerializationAttributes on the parameter, method, or class.
/// </summary>
/// <param name="context">The serialization context to evaluate.</param>
/// <returns>The EventLevel at which to enable serialization for the given context.</returns>
public override EventLevel? GetEventLevelForContext(TraceSerializationContext context)
{
return null;
}
