/// <summary>
/// Creates a serializer for the given type and settings.
/// </summary>
/// <typeparam name="TExample">The user type to serialize.</typeparam>
/// <param name="settings"></param>
/// <returns></returns>
public static VowpalWabbitSerializerCompiled <TExample> CreateSerializer <TExample>(VowpalWabbitSettings settings = null)
{
List <FeatureExpression> allFeatures = null;
Type cacheKey = null;
if (settings != null && settings.AllFeatures != null)
{
allFeatures = settings.AllFeatures;
}
else
{
// only cache non-string generating serializer
if (!settings.EnableStringExampleGeneration)
{
cacheKey = typeof(TExample);
object serializer;
if (SerializerCache.TryGetValue(cacheKey, out serializer))
{
return((VowpalWabbitSerializerCompiled <TExample>)serializer);
}
}
// TOOD: enhance caching based on feature list & featurizer set
// if no feature mapping is provided, use [Feature] annotation on provided type.
Func <PropertyInfo, FeatureAttribute, bool> propertyPredicate = null;
switch (settings.FeatureDiscovery)
{
case VowpalWabbitFeatureDiscovery.Default:
propertyPredicate = (_, attr) => attr != null;
break;
case VowpalWabbitFeatureDiscovery.All:
propertyPredicate = (_, __) => true;
break;
}
allFeatures = AnnotationInspector.ExtractFeatures(typeof(TExample), propertyPredicate).ToList();
}
// need at least a single feature to do something sensible
if (allFeatures == null || allFeatures.Count == 0)
{
return(null);
}
var newSerializer = new VowpalWabbitSerializerCompiled <TExample>(
allFeatures,
settings == null ? null : settings.CustomFeaturizer,
!settings.EnableStringExampleGeneration);
if (cacheKey != null)
{
SerializerCache[cacheKey] = newSerializer;
}
return(newSerializer);
}
/// <summary>
/// Creates a serializer for the given type and settings.
/// </summary>
/// <typeparam name="TExample">The user type to serialize.</typeparam>
/// <param name="settings"></param>
/// <returns></returns>
public static IVowpalWabbitSerializerCompiler <TExample> CreateSerializer <TExample>(VowpalWabbitSettings settings = null)
{
Schema schema = null;
Type cacheKey = null;
if (settings != null && settings.Schema != null)
{
schema = settings.Schema;
}
else
{
// only cache non-string generating serializer
if (!settings.EnableStringExampleGeneration)
{
cacheKey = typeof(TExample);
object serializer;
if (SerializerCache.TryGetValue(cacheKey, out serializer))
{
return((IVowpalWabbitSerializerCompiler <TExample>)serializer);
}
}
if (settings.FeatureDiscovery == VowpalWabbitFeatureDiscovery.Json)
{
schema = AnnotationJsonInspector.CreateSchema(typeof(TExample), settings.PropertyConfiguration);
var multiExampleSerializerCompiler = VowpalWabbitMultiExampleSerializerCompiler.TryCreate <TExample>(settings, schema);
if (multiExampleSerializerCompiler != null)
{
return(multiExampleSerializerCompiler);
}
}
else
{
// TODO: enhance caching based on feature list & featurizer set
// if no feature mapping is provided, use [Feature] annotation on provided type.
Func <PropertyInfo, FeatureAttribute, bool> propertyPredicate = null;
Func <PropertyInfo, LabelAttribute, bool> labelPredicate = null;
switch (settings.FeatureDiscovery)
{
case VowpalWabbitFeatureDiscovery.Default:
propertyPredicate = (_, attr) => attr != null;
labelPredicate = (_, attr) => attr != null;
break;
case VowpalWabbitFeatureDiscovery.All:
propertyPredicate = (_, __) => true;
labelPredicate = (_, __) => true;
break;
}
schema = AnnotationInspector.CreateSchema(typeof(TExample), propertyPredicate, labelPredicate);
}
}
// need at least a single feature to do something sensible
if (schema == null || schema.Features.Count == 0)
{
return(null);
}
var newSerializer = new VowpalWabbitSingleExampleSerializerCompiler <TExample>(
schema,
settings == null ? null : settings.CustomFeaturizer,
!settings.EnableStringExampleGeneration);
if (cacheKey != null)
{
SerializerCache[cacheKey] = newSerializer;
}
return(newSerializer);
}