/// <summary>
/// Initializes a new instance of the <see cref="CompositeQuery"/> class for a
/// non-root composite query.
/// </summary>
/// <param name="parentCompositeQuery">The composite query that provides the data for the next level up in the composite resource.</param>
/// <param name="displayName">The name to be used for the collection of data represented by the composite query.</param>
/// <param name="orderedFieldNames">The names of the fields in selection order.</param>
/// <param name="futureQuery">The results of the query, exposed by NHibernate as a collection of <see cref="Hashtable"/> instances.</param>
/// <param name="isSingleItemResult">Indicates that the results should be treated as a single result in the output.</param>
public CompositeQuery(
CompositeQuery parentCompositeQuery,
string displayName,
string[] orderedFieldNames,
IEnumerable <object> futureQuery,
bool isSingleItemResult)
{
DisplayName = displayName;
OrderedFieldNames = orderedFieldNames;
IsSingleItemResult = isSingleItemResult;
_parentCompositeQuery = parentCompositeQuery;
_keyFields = new Lazy <string[]>(() => GetKeyFields(_futureQueryEnumerator.Value));
_dataFields = new Lazy <string[]>(() => GetDataFields(_futureQueryEnumerator.Value));
_dataByParentKey = new Lazy <IDictionary <string, List <Hashtable> > >(() => GetDataByParentKey(_futureQueryEnumerator.Value));
_futureQueryEnumerator = new Lazy <IEnumeratorWithCompletion>(
() =>
{
var enumerator = futureQuery.GetEnumerator();
if (enumerator.MoveNext())
{
return(new EnumeratorWithCompletionWrapper(enumerator));
}
return(null);
});
ChildQueries = new List <CompositeQuery>();
}
private bool TryBuildCompositeQuery(
XElement compositeDefinition,
IResourceModel resourceModel,
IDictionary <string, CompositeSpecificationParameter> filterCriteria,
IDictionary <string, object> queryStringParameters,
out CompositeQuery compositeQuery)
{
compositeQuery = null;
var aliasGenerator = new AliasGenerator(CompositeDefinitionHelper.AliasPrefix);
var builderContext = new HqlBuilderContext(
new StringBuilder(),
new StringBuilder(),
new StringBuilder(),
new StringBuilder(),
new Dictionary <string, object>(StringComparer.InvariantCultureIgnoreCase),
null,
1,
filterCriteria,
queryStringParameters,
new Dictionary <string, string>(StringComparer.InvariantCultureIgnoreCase),
aliasGenerator);
compositeQuery = _compositeDefinitionProcessor.Process(compositeDefinition, resourceModel, builderContext);
return(compositeQuery != null);
}
public object Get(
XElement compositeDefinition,
IDictionary <string, CompositeSpecificationParameter> parameters,
IDictionary <string, object> queryStringParameters,
NullValueHandling nullValueHandling = NullValueHandling.Ignore)
{
var resourceModel = GetResourceModel();
bool closeSession = false;
CompositeQuery query = null;
object result = null;
try
{
if (!CurrentSessionContext.HasBind(_sessionFactory))
{
CurrentSessionContext.Bind(_sessionFactory.OpenSession());
closeSession = true;
}
var fieldSelections = GetFieldSelections(queryStringParameters);
if (TryBuildCompositeQuery(
compositeDefinition,
resourceModel,
parameters,
queryStringParameters,
out query))
{
result = ProcessResults(query, fieldSelections, nullValueHandling);
// Handle Single item requests
if (query.IsSingleItemResult && result == null)
{
throw new NotFoundException("The specified resource could not be found.");
}
}
else
{
// Return an appropriate response for an empty result
if (IsSingleItemRequest(compositeDefinition, resourceModel, queryStringParameters))
{
throw new NotFoundException("The specified resource could not be found.");
}
result = new List <IDictionary>();
}
}
catch (Exception e)
{
_logger.Error(e);
throw;
}
finally
{
if (closeSession)
{
_sessionFactory.GetCurrentSession()
.Close();
}
}
return(result);
}
public IList <IDictionary> ProcessResults(
CompositeQuery query,
Hashtable parentRow,
string[] parentKeys,
IReadOnlyList <SelectedResourceMember> fieldSelections,
NullValueHandling nullValueHandling)
{
var results = new List <IDictionary>();
var currentEnumerator = query.GetEnumerator(parentRow);
do
{
// Nothing to enumerate?
if (currentEnumerator == null || currentEnumerator.IsComplete)
{
return(results);
}
// Get current row
var currentRow = (Hashtable)currentEnumerator.Current;
if (currentRow == null)
{
break;
}
// If the child is outside the context of the parent, quit processing
if (parentRow != null && !IsChildRow(parentKeys, parentRow, currentRow))
{
break;
}
// Convert the row to serializable form
var resultItem = GetItem(currentRow, query.DataFields, query.OrderedFieldNames, fieldSelections, nullValueHandling);
// Process the children
foreach (var childQuery in query.ChildQueries)
{
SelectedResourceMember selectedMember = null;
string childCollectionName = childQuery.DisplayName;
// Check to see if this collection should be included
if (fieldSelections != null && fieldSelections.Count > 0)
{
selectedMember = fieldSelections.FirstOrDefault(x => x.Equals(childCollectionName) || x.Equals("*"));
if (selectedMember == null)
{
continue;
}
}
resultItem[childCollectionName] =
ProcessResults(
childQuery,
currentRow,
query.KeyFields,
selectedMember == null
? null
: selectedMember.Children,
nullValueHandling)
.ApplyCardinality(childQuery.IsSingleItemResult);
}
results.Add(resultItem);
}while (currentEnumerator.MoveNext());
return(results);
}
public object ProcessResults(CompositeQuery query, IReadOnlyList <SelectedResourceMember> fieldSelections, NullValueHandling nullValueHandling)
{
return(ProcessResults(query, null, null, fieldSelections, nullValueHandling)
.ApplyCardinality(query.IsSingleItemResult));
}