protected void SerializeLinkedResources(Stream writeStream, JsonWriter writer, JsonSerializer serializer, RelationAggregator aggregator)
{
/* This is a bit messy, because we may add items of a given type to the
* set we are currently processing. Not only is this an issue because you
* can't modify a set while you're enumerating it (hence why we make a
* copy first), but we need to catch the newly added objects and process
* them as well. So, we have to keep making passes until we detect that
* we haven't added any new objects to any of the appendices.
*/
Dictionary <Type, ISet <object> >
processed = new Dictionary <Type, ISet <object> >(),
toBeProcessed = new Dictionary <Type, ISet <object> >(); // is this actually necessary?
/* On top of that, we need a new JsonWriter for each appendix--because we
* may write objects of type A, then while processing type B find that
* we need to write more objects of type A! So we can't keep appending
* to the same writer.
*/
/* Oh, and we have to keep a reference to the TextWriter of the JsonWriter
* because there's no member to get it back out again. ?!?
* */
Dictionary <Type, KeyValuePair <JsonWriter, StringWriter> > writers = new Dictionary <Type, KeyValuePair <JsonWriter, StringWriter> >();
int numAdditions;
do
{
numAdditions = 0;
Dictionary <Type, ISet <object> > appxs = new Dictionary <Type, ISet <object> >(aggregator.Appendices); // shallow clone, in case we add a new type during enumeration!
foreach (KeyValuePair <Type, ISet <object> > apair in appxs)
{
Type type = apair.Key;
ISet <object> appendix = apair.Value;
JsonWriter jw;
if (writers.ContainsKey(type))
{
jw = writers[type].Key;
}
else
{
// Setup and start the writer for this type...
StringWriter sw = new StringWriter();
jw = new JsonTextWriter(sw);
writers[type] = new KeyValuePair <JsonWriter, StringWriter>(jw, sw);
jw.WriteStartArray();
}
HashSet <object> tbp;
if (processed.ContainsKey(type))
{
toBeProcessed[type] = tbp = new HashSet <object>(appendix.Except(processed[type]));
}
else
{
toBeProcessed[type] = tbp = new HashSet <object>(appendix);
processed[type] = new HashSet <object>();
}
if (tbp.Count > 0)
{
numAdditions += tbp.Count;
foreach (object obj in tbp)
{
Serialize(obj, writeStream, jw, serializer, aggregator); // Note, not writer, but jw--we write each type to its own JsonWriter and combine them later.
}
processed[type].UnionWith(tbp);
}
//TODO: Add traversal depth limit??
}
} while (numAdditions > 0);
if (aggregator.Appendices.Count > 0)
{
writer.WritePropertyName("linked");
writer.WriteStartObject();
// Okay, we should have captured everything now. Now combine the type writers into the main writer...
foreach (KeyValuePair <Type, KeyValuePair <JsonWriter, StringWriter> > apair in writers)
{
apair.Value.Key.WriteEnd(); // close off the array
writer.WritePropertyName(_modelManager.GetJsonKeyForType(apair.Key));
writer.WriteRawValue(apair.Value.Value.ToString()); // write the contents of the type JsonWriter's StringWriter to the main JsonWriter
}
writer.WriteEndObject();
}
}
protected void SerializeMany(object value, Stream writeStream, JsonWriter writer, JsonSerializer serializer, RelationAggregator aggregator)
{
writer.WriteStartArray();
foreach (object singleVal in (IEnumerable)value)
{
this.Serialize(singleVal, writeStream, writer, serializer, aggregator);
}
writer.WriteEndArray();
}
protected void Serialize(object value, Stream writeStream, JsonWriter writer, JsonSerializer serializer, RelationAggregator aggregator)
{
writer.WriteStartObject();
// Do the Id now...
writer.WritePropertyName("id");
var idProp = _modelManager.GetIdProperty(value.GetType());
writer.WriteValue(GetValueForIdProperty(idProp, value));
// Leverage the cached map to avoid another costly call to System.Type.GetProperties()
PropertyInfo[] props = _modelManager.GetProperties(value.GetType());
// Do non-model properties first, everything else goes in "links"
//TODO: Unless embedded???
IList <PropertyInfo> modelProps = new List <PropertyInfo>();
foreach (PropertyInfo prop in props)
{
if (prop == idProp)
{
continue;
}
if (this.CanWriteTypeAsPrimitive(prop.PropertyType))
{
if (prop.GetCustomAttributes().Any(attr => attr is JsonIgnoreAttribute))
{
continue;
}
// numbers, strings, dates...
writer.WritePropertyName(_modelManager.GetJsonKeyForProperty(prop));
var propertyValue = prop.GetValue(value, null);
if (prop.PropertyType == typeof(string) &&
prop.GetCustomAttributes().Any(attr => attr is SerializeStringAsRawJsonAttribute))
{
if (propertyValue == null)
{
writer.WriteNull();
}
else
{
var minifiedValue = JsonHelpers.MinifyJson((string)propertyValue);
writer.WriteRawValue(minifiedValue);
}
}
else
{
serializer.Serialize(writer, propertyValue);
}
}
else
{
modelProps.Add(prop);
continue;
}
}
// Now do other stuff
if (modelProps.Count() > 0)
{
writer.WritePropertyName("links");
writer.WriteStartObject();
}
foreach (PropertyInfo prop in modelProps)
{
bool skip = false, iip = false;
string lt = null;
SerializeAsOptions sa = SerializeAsOptions.Ids;
object[] attrs = prop.GetCustomAttributes(true);
foreach (object attr in attrs)
{
Type attrType = attr.GetType();
if (typeof(JsonIgnoreAttribute).IsAssignableFrom(attrType))
{
skip = true;
continue;
}
if (typeof(IncludeInPayload).IsAssignableFrom(attrType))
{
iip = ((IncludeInPayload)attr).Include;
}
if (typeof(SerializeAs).IsAssignableFrom(attrType))
{
sa = ((SerializeAs)attr).How;
}
if (typeof(LinkTemplate).IsAssignableFrom(attrType))
{
lt = ((LinkTemplate)attr).TemplateString;
}
}
if (skip)
{
continue;
}
writer.WritePropertyName(_modelManager.GetJsonKeyForProperty(prop));
// Look out! If we want to SerializeAs a link, computing the property is probably
// expensive...so don't force it just to check for null early!
if (sa != SerializeAsOptions.Link && prop.GetValue(value, null) == null)
{
writer.WriteNull();
continue;
}
// Now look for enumerable-ness:
if (typeof(IEnumerable <Object>).IsAssignableFrom(prop.PropertyType))
{
switch (sa)
{
case SerializeAsOptions.Ids:
//writer.WritePropertyName(ContractResolver._modelManager.GetJsonKeyForProperty(prop));
IEnumerable <object> items = (IEnumerable <object>)prop.GetValue(value, null);
if (items == null)
{
writer.WriteValue((IEnumerable <object>)null); //TODO: Is it okay with the spec and Ember Data to return null for an empty array?
break; // LOOK OUT! Ending this case block early here!!!
}
this.WriteIdsArrayJson(writer, items, serializer);
if (iip)
{
Type itemType;
if (prop.PropertyType.IsGenericType)
{
itemType = prop.PropertyType.GetGenericArguments()[0];
}
else
{
// Must be an array at this point, right??
itemType = prop.PropertyType.GetElementType();
}
if (aggregator != null)
{
aggregator.Add(itemType, items); // should call the IEnumerable one...right?
}
}
break;
case SerializeAsOptions.Link:
if (lt == null)
{
throw new JsonSerializationException("A property was decorated with SerializeAs(SerializeAsOptions.Link) but no LinkTemplate attribute was provided.");
}
//TODO: Check for "{0}" in linkTemplate and (only) if it's there, get the Ids of all objects and "implode" them.
string href = String.Format(lt, null, GetIdFor(value));
//writer.WritePropertyName(ContractResolver._modelManager.GetJsonKeyForProperty(prop));
//TODO: Support ids and type properties in "link" object
writer.WriteStartObject();
writer.WritePropertyName("href");
writer.WriteValue(href);
writer.WriteEndObject();
break;
case SerializeAsOptions.Embedded:
// Not really supported by Ember Data yet, incidentally...but easy to implement here.
//writer.WritePropertyName(ContractResolver._modelManager.GetJsonKeyForProperty(prop));
//serializer.Serialize(writer, prop.GetValue(value, null));
this.Serialize(prop.GetValue(value, null), writeStream, writer, serializer, aggregator);
break;
}
}
else
{
var propertyValue = prop.GetValue(value, null);
if (propertyValue == null)
{
writer.WriteNull();
}
else
{
string objId = GetIdFor(propertyValue);
switch (sa)
{
case SerializeAsOptions.Ids:
//writer.WritePropertyName(ContractResolver._modelManager.GetJsonKeyForProperty(prop));
serializer.Serialize(writer, objId);
if (iip)
{
if (aggregator != null)
{
aggregator.Add(prop.PropertyType, prop.GetValue(value, null));
}
}
break;
case SerializeAsOptions.Link:
if (lt == null)
{
throw new JsonSerializationException(
"A property was decorated with SerializeAs(SerializeAsOptions.Link) but no LinkTemplate attribute was provided.");
}
string link = String.Format(lt, objId,
GetIdFor(value)); //value.GetType().GetProperty("Id").GetValue(value, null));
//writer.WritePropertyName(ContractResolver._modelManager.GetJsonKeyForProperty(prop));
writer.WriteStartObject();
writer.WritePropertyName("href");
writer.WriteValue(link);
writer.WriteEndObject();
break;
case SerializeAsOptions.Embedded:
// Not really supported by Ember Data yet, incidentally...but easy to implement here.
//writer.WritePropertyName(ContractResolver._modelManager.GetJsonKeyForProperty(prop));
//serializer.Serialize(writer, prop.GetValue(value, null));
this.Serialize(prop.GetValue(value, null), writeStream, writer, serializer, aggregator);
break;
}
}
}
}
if (modelProps.Count() > 0)
{
writer.WriteEndObject();
}
writer.WriteEndObject();
}
public override Task WriteToStreamAsync(System.Type type, object value, Stream writeStream, System.Net.Http.HttpContent content, System.Net.TransportContext transportContext)
{
RelationAggregator aggregator;
lock (this.RelationAggregators)
{
if (this.RelationAggregators.ContainsKey(writeStream))
{
aggregator = this.RelationAggregators[writeStream];
}
else
{
aggregator = new RelationAggregator();
this.RelationAggregators[writeStream] = aggregator;
}
}
var contentHeaders = content == null ? null : content.Headers;
var effectiveEncoding = SelectCharacterEncoding(contentHeaders);
JsonWriter writer = this.CreateJsonWriter(typeof(object), writeStream, effectiveEncoding);
JsonSerializer serializer = this.CreateJsonSerializer();
if (_errorSerializer.CanSerialize(type))
{
// `value` is an error
_errorSerializer.SerializeError(value, writeStream, writer, serializer);
}
else
{
Type valtype = GetSingleType(value.GetType());
if (_modelManager.IsSerializedAsMany(value.GetType()))
{
aggregator.AddPrimary(valtype, (IEnumerable <object>)value);
}
else
{
aggregator.AddPrimary(valtype, value);
}
//writer.Formatting = Formatting.Indented;
var root = _modelManager.GetJsonKeyForType(type);
writer.WriteStartObject();
writer.WritePropertyName(root);
if (_modelManager.IsSerializedAsMany(value.GetType()))
{
this.SerializeMany(value, writeStream, writer, serializer, aggregator);
}
else
{
this.Serialize(value, writeStream, writer, serializer, aggregator);
}
// Include links from aggregator
SerializeLinkedResources(writeStream, writer, serializer, aggregator);
writer.WriteEndObject();
}
writer.Flush();
lock (this.RelationAggregators)
{
this.RelationAggregators.Remove(writeStream);
}
//return base.WriteToStreamAsync(type, obj as object, writeStream, content, transportContext);
//TODO: For now we won't worry about optimizing this down into smaller async parts, we'll just do it all synchronous. So...
// Just return a completed task... from http://stackoverflow.com/a/17527551/489116
var tcs = new TaskCompletionSource <object>();
tcs.SetResult(null);
return(tcs.Task);
}
