/// <summary>
/// Registers a 'member' entry for the relationship.
/// </summary>
private void RegisterRelationshipMember(JsonQueryResult result, EntityPackageContext entityPackageContext, RelationshipData rel)
{
var members = result.Members;
long relId = rel.RelationshipTypeId.Id;
// Determine if there is an existing member registered for this relationship.
// And create one if necessary.
JsonMember member;
if (!members.TryGetValue(relId, out member))
{
member = new JsonMember();
members.Add(relId, member);
}
// Then we ensure there is information for the member in the particular direction that we're interested in.
JsonRelationshipMember relMember = rel.IsReverseActual ? member.Reverse : member.Forward;
if (relMember == null)
{
relMember = new JsonRelationshipMember();
relMember.Alias = GetAliasString(rel.RelationshipTypeId);
relMember.IsLookup = rel.IsLookup;
if (rel.IsReverseActual)
{
member.Reverse = relMember;
}
else
{
member.Forward = relMember;
}
}
else if (relMember.Alias == null && rel.RelationshipTypeId.Alias != null)
{
relMember.Alias = GetAliasString(rel.RelationshipTypeId);
}
}
/// <summary>
/// Store fields into the JSON entity structure.
/// </summary>
/// <param name="entityData">The entity being read.</param>
/// <param name="entityPackageContext"></param>
/// <param name="entityJson">JSON for holding member data for the individual entity.</param>
/// <returns></returns>
private void AppendFieldsToEntity(JsonQueryResult result, EntityData entityData, EntityPackageContext entityPackageContext,
Dictionary <string, object> entityJson)
{
var members = result.Members;
// Visit fields
foreach (var field in entityData.Fields)
{
long fieldId = field.FieldId.Id;
// Register the field member
JsonMember member;
if (members.TryGetValue(fieldId, out member))
{
if (field.FieldId.Alias != null && member.Alias == null)
{
member.Alias = GetAliasString(field.FieldId);
}
}
else
{
member = new JsonMember();
member.Alias = GetAliasString(field.FieldId);
member.DataType = DataTypeHelper.FromDatabaseType(field.Value.Type).ToString();
members.Add(fieldId, member);
}
object value = field.Value.Value;
// Ensure empty strings are represented as nulls - this is by design!
if (value is string && ((string)value).Length == 0)
{
value = null;
}
// Store the data in the entity
entityJson[fieldId.ToString(CultureInfo.InvariantCulture)] = value;
}
}
/// <summary>
/// Store relationships into the JSON entity structure.
/// </summary>
/// <param name="entityData">The entity being read.</param>
/// <param name="entityPackageContext"></param>
/// <param name="entityJson">JSON for holding member data for the individual entity.</param>
/// <returns></returns>
private void AppendRelationshipsToEntity(JsonQueryResult result, EntityData entityData, EntityPackageContext entityPackageContext,
Dictionary <string, object> entityJson)
{
// Visit relationships
foreach (var rel in entityData.Relationships)
{
// Register the relationship member metadata
// Note: we need to first see if there is a container for the relationship in either direction
RegisterRelationshipMember(result, entityPackageContext, rel);
// Get relationship data.
// Holds a mixture of either long or JsonRelationshipInstance
var relResult = new List <object>();
foreach (var relInst in rel.Instances)
{
// If we have a relationship instance, send a complex object
// Otherwise just send the ID of the entity we're relating to.
if (relInst.RelationshipInstanceEntity != null)
{
var relInstResult = new JsonRelationshipInstance();
if (relInst.Entity != null)
{
relInstResult.EntityId = relInst.Entity.Id.Id;
}
relInstResult.RelationshipInstance = relInst.RelationshipInstanceEntity.Id.Id;
relResult.Add(relInstResult);
// Recursively visit the relationship instance entity
AppendEntityToResult(result, relInst.RelationshipInstanceEntity, entityPackageContext);
}
else if (relInst.Entity != null)
{
long relatedId = relInst.Entity.Id.Id;
relResult.Add(relatedId);
}
// Recursively visit the related entity
AppendEntityToResult(result, relInst.Entity, entityPackageContext);
}
// Store the data in the entity
StoreRelationshipData(entityJson, rel, relResult);
}
}
/// <summary>
/// Store an entity into the JSON result structure.
/// </summary>
private void AppendEntityToResult(JsonQueryResult result, EntityData entityData, EntityPackageContext entityPackageContext)
{
long entityKey = entityData.Id.Id;
// Avoid circular loops within a query.
if (entityPackageContext.EntitiesVisited.Contains(entityKey))
{
return;
}
entityPackageContext.EntitiesVisited.Add(entityKey);
Dictionary <string, object> entityJson;
if (!result.Entities.TryGetValue(entityKey, out entityJson))
{
entityJson = new Dictionary <string, object>();
result.Entities.Add(entityKey, entityJson);
}
AppendFieldsToEntity(result, entityData, entityPackageContext, entityJson);
AppendRelationshipsToEntity(result, entityData, entityPackageContext, entityJson);
if (!entityJson.Any())
{
// Note: always add, then remove if not needed. Otherwise it's not present in the dictionary when we recurse,
// which can lead to infinite loops.
result.Entities.Remove(entityKey);
}
}
