private static string GetRootElementName(ODataPath path)
{
if (path != null)
{
ODataPathSegment lastSegment = path.Segments.LastOrDefault();
if (lastSegment != null)
{
OperationSegment actionSegment = lastSegment as OperationSegment;
if (actionSegment != null)
{
IEdmAction action = actionSegment.Operations.Single() as IEdmAction;
if (action != null)
{
return(action.Name);
}
}
PropertySegment propertyAccessSegment = lastSegment as PropertySegment;
if (propertyAccessSegment != null)
{
return(propertyAccessSegment.Property.Name);
}
}
}
return(null);
}
// Determine action from readContext
// This function is copied from default ODataActionPayloadDeserializer because it cannot be inherited
private static IEdmAction GetAction(ODataDeserializerContext readContext)
{
if (readContext == null)
{
throw new ArgumentNullException(nameof(readContext));
}
ODataPath path = readContext.Path;
if (path == null || path.Segments.Count == 0)
{
throw new SerializationException("OData Path is missing");
}
IEdmAction action = null;
if (path.PathTemplate == "~/unboundaction")
{
// only one segment, it may be an unbound action
OperationImportSegment unboundActionSegment = path.Segments.Last() as OperationImportSegment;
if (unboundActionSegment != null)
{
IEdmActionImport actionImport = unboundActionSegment.OperationImports.First() as IEdmActionImport;
if (actionImport != null)
{
action = actionImport.Action;
}
}
}
else
{
// otherwise, it may be a bound action
OperationSegment actionSegment = path.Segments.Last() as OperationSegment;
if (actionSegment != null)
{
action = actionSegment.Operations.First() as IEdmAction;
}
}
if (action == null)
{
throw new SerializationException("Request is not an action invocation");
}
return(action);
}
// This function is used to determine whether an OData path includes operation (import) path segments.
// We use this function to make sure the value of ODataUri.Path in ODataMessageWriterSettings is null
// when any path segment is an operation. ODL will try to calculate the context URL if the ODataUri.Path
// equals to null.
private static bool IsOperationPath(ODataPath path)
{
if (path == null)
{
return(false);
}
foreach (ODataPathSegment segment in path.Segments)
{
if (segment is OperationSegment ||
segment is OperationImportSegment)
{
return(true);
}
}
return(false);
}
static bool IsNextSegmentOfType <T>(AspNet.OData.Routing.ODataPath path, int currentPos)
{
var maxPos = path.Segments.Count - 1;
if (maxPos <= currentPos)
{
return(false);
}
var nextSegment = path.Segments[currentPos + 1];
if (nextSegment is T)
{
return(true);
}
if (nextSegment is TypeSegment && maxPos >= currentPos + 2 && path.Segments[currentPos + 2] is T)
{
return(true);
}
return(false);
}
static bool IsNextSegmentKey(AspNet.OData.Routing.ODataPath path, int currentPos)
{
return(IsNextSegmentOfType <KeySegment>(path, currentPos));
}
internal static IScopesEvaluator ExtractPermissionsForRequest(this IEdmModel model, string method, AspNet.OData.Routing.ODataPath odataPath)
{
var template = odataPath.PathTemplate;
ODataPathSegment prevSegment = null;
var segments = new List <ODataPathSegment>();
// this combines the permission scopes across path segments
// with a logical AND
var permissionsChain = new WithAndScopesCombiner();
var lastSegmentIndex = odataPath.Segments.Count - 1;
if (template.EndsWith("$ref", StringComparison.OrdinalIgnoreCase))
{
// for ref segments, we apply the permission of the entity that contains the navigation property
// e.g. for GET Customers(10)/Products/$ref, we apply the read key permissions of Customers
// for GET TopCustomer/Products/$ref, we apply the read permissions of TopCustomer
// for DELETE Customers(10)/Products(10)/$ref we apply the update permissions of Customers
lastSegmentIndex = odataPath.Segments.Count - 2;
while (!(odataPath.Segments[lastSegmentIndex] is KeySegment || odataPath.Segments[lastSegmentIndex] is SingletonSegment || odataPath.Segments[lastSegmentIndex] is NavigationPropertySegment) &&
lastSegmentIndex > 0)
{
lastSegmentIndex--;
}
}
for (int i = 0; i <= lastSegmentIndex; i++)
{
var segment = odataPath.Segments[i];
if (segment is EntitySetSegment ||
segment is SingletonSegment ||
segment is NavigationPropertySegment ||
segment is OperationSegment ||
segment is OperationImportSegment ||
segment is KeySegment ||
segment is PropertySegment)
{
var parent = prevSegment;
var isPropertyAccess = IsNextSegmentOfType <PropertySegment>(odataPath, i) ||
IsNextSegmentOfType <NavigationPropertyLinkSegment>(odataPath, i) ||
IsNextSegmentOfType <NavigationPropertySegment>(odataPath, i);
prevSegment = segment;
segments.Add(segment);
// if nested segment, extract navigation restrictions of root
// else extract entity/set restrictions
if (segment is EntitySetSegment entitySetSegment)
{
// if Customers(key), then we'll handle it when we reach the key segment
// so that we can properly handle ReadByKeyRestrictions
if (IsNextSegmentKey(odataPath, i))
{
continue;
}
// if Customers/UnboundFunction, then we'll handle it when we reach the operation segment
if (IsNextSegmentOfType <OperationSegment>(odataPath, i))
{
continue;
}
IScopesEvaluator permissions;
permissions = GetNavigationPropertyCrudPermisions(
segments,
false,
model,
method);
if (permissions is DefaultScopesEvaluator)
{
permissions = GetNavigationSourceCrudPermissions(entitySetSegment.EntitySet, model, method);
}
var handler = new WithOrScopesCombiner(permissions);
permissionsChain.Add(handler);
}
else if (segment is SingletonSegment singletonSegment)
{
// if Customers/UnboundFunction, then we'll handle it when we reach the operation segment
if (IsNextSegmentOfType <OperationSegment>(odataPath, i))
{
continue;
}
if (isPropertyAccess)
{
var propertyPermissions = GetSingletonPropertyOperationPermissions(singletonSegment.Singleton, model, method);
permissionsChain.Add(new WithOrScopesCombiner(propertyPermissions));
}
else
{
var permissions = GetNavigationSourceCrudPermissions(singletonSegment.Singleton, model, method);
permissionsChain.Add(new WithOrScopesCombiner(permissions));
}
}
else if (segment is KeySegment keySegment)
{
// if Customers/UnboundFunction, then we'll handle it when we reach the operation segment
if (IsNextSegmentOfType <OperationSegment>(odataPath, i))
{
continue;
}
var entitySet = keySegment.NavigationSource as IEdmEntitySet;
var permissions = isPropertyAccess ?
GetEntityPropertyOperationPermissions(entitySet, model, method) :
GetEntityCrudPermissions(entitySet, model, method);
var evaluator = new WithOrScopesCombiner(permissions);
if (parent is NavigationPropertySegment)
{
var nestedPermissions = isPropertyAccess ?
GetNavigationPropertyPropertyOperationPermisions(segments, isTargetByKey: true, model, method) :
GetNavigationPropertyCrudPermisions(segments, isTargetByKey: true, model, method);
evaluator.Add(nestedPermissions);
}
permissionsChain.Add(evaluator);
}
else if (segment is NavigationPropertySegment navSegment)
{
// if Customers/UnboundFunction, then we'll handle it when we reach there
if (IsNextSegmentOfType <OperationSegment>(odataPath, i))
{
continue;
}
// if Customers(key), then we'll handle it when we reach the key segment
// so that we can properly handle ReadByKeyRestrictions
if (IsNextSegmentKey(odataPath, i))
{
continue;
}
var topLevelPermissions = GetNavigationSourceCrudPermissions(navSegment.NavigationSource as IEdmVocabularyAnnotatable, model, method);
var segmentEvaluator = new WithOrScopesCombiner(topLevelPermissions);
var nestedPermissions = GetNavigationPropertyCrudPermisions(
segments,
isTargetByKey: false,
model,
method);
segmentEvaluator.Add(nestedPermissions);
permissionsChain.Add(segmentEvaluator);
}
else if (segment is OperationImportSegment operationImportSegment)
{
var annotations = operationImportSegment.OperationImports.First().Operation.VocabularyAnnotations(model);
var permissions = GetOperationPermissions(annotations);
permissionsChain.Add(new WithOrScopesCombiner(permissions));
}
else if (segment is OperationSegment operationSegment)
{
var annotations = operationSegment.Operations.First().VocabularyAnnotations(model);
var operationPermissions = GetOperationPermissions(annotations);
permissionsChain.Add(new WithOrScopesCombiner(operationPermissions));
}
}
}
return(permissionsChain);
}
/// <summary>
/// Read and serialize outgoing object to HTTP request stream.
/// </summary>
internal static void WriteToStream(
Type type,
object value,
IEdmModel model,
Uri baseAddress,
MediaTypeHeaderValue contentType,
IUrlHelper internalUrlHelper,
HttpRequest internalRequest,
IHeaderDictionary internalRequestHeaders,
Func <IServiceProvider, ODataMigrationMessageWrapper> getODataMessageWrapper,
Func <IEdmTypeReference, ODataSerializer> getEdmTypeSerializer,
Func <Type, ODataSerializer> getODataPayloadSerializer,
Func <ODataSerializerContext> getODataSerializerContext)
{
if (model == null)
{
throw new InvalidOperationException("Request must have model");
}
ODataSerializer serializer = GetSerializer(type, value, internalRequest, getEdmTypeSerializer, getODataPayloadSerializer);
// special case: if the top level serializer is an ODataPrimitiveSerializer then swap it out for an ODataMigrationPrimitiveSerializer
// This only applies to the top level because inline primitives are translated but top level primitives are not, unless we use a customized serializer.
if (serializer is ODataPrimitiveSerializer)
{
serializer = new ODataMigrationPrimitiveSerializer();
}
ODataPath path = internalRequest.ODataFeature().Path;
IEdmNavigationSource targetNavigationSource = path == null ? null : path.NavigationSource;
// serialize a response
string preferHeader = GetRequestPreferHeader(internalRequestHeaders);
string annotationFilter = null;
if (!String.IsNullOrEmpty(preferHeader))
{
ODataMigrationMessageWrapper messageWrapper = getODataMessageWrapper(null);
messageWrapper.SetHeader("Prefer", preferHeader);
annotationFilter = messageWrapper.PreferHeader().AnnotationFilter;
}
ODataMigrationMessageWrapper responseMessageWrapper = getODataMessageWrapper(internalRequest.GetRequestContainer());
IODataResponseMessage responseMessage = responseMessageWrapper;
if (annotationFilter != null)
{
responseMessage.PreferenceAppliedHeader().AnnotationFilter = annotationFilter;
}
ODataMessageWriterSettings writerSettings = internalRequest.GetWriterSettings();
writerSettings.BaseUri = baseAddress;
writerSettings.Version = ODataVersion.V4; // Todo how to specify v3? Maybe don't because reading as v4
writerSettings.Validations = writerSettings.Validations & ~ValidationKinds.ThrowOnUndeclaredPropertyForNonOpenType;
string metadataLink = internalUrlHelper.CreateODataLink(MetadataSegment.Instance);
if (metadataLink == null)
{
throw new SerializationException("Unable to determine metadata url");
}
writerSettings.ODataUri = new ODataUri
{
ServiceRoot = baseAddress,
SelectAndExpand = internalRequest.ODataFeature()?.SelectExpandClause,
Apply = internalRequest.ODataFeature().ApplyClause,
Path = (path == null || IsOperationPath(path)) ? null : path.Path,
};
ODataMetadataLevel metadataLevel = ODataMetadataLevel.MinimalMetadata;
if (contentType != null)
{
IEnumerable <KeyValuePair <string, string> > parameters =
contentType.Parameters.Select(val => new KeyValuePair <string, string>(val.Name.Value, val.Value.Value));
metadataLevel = ODataMediaTypes.GetMetadataLevel(contentType.MediaType.Value, parameters);
}
using (ODataMessageWriter messageWriter = new ODataMessageWriter(responseMessage, writerSettings, model))
{
ODataSerializerContext writeContext = getODataSerializerContext();
writeContext.NavigationSource = targetNavigationSource;
writeContext.Model = model;
writeContext.RootElementName = GetRootElementName(path) ?? "root";
writeContext.SkipExpensiveAvailabilityChecks = serializer.ODataPayloadKind == ODataPayloadKind.ResourceSet;
writeContext.Path = path;
writeContext.SelectExpandClause = internalRequest.ODataFeature()?.SelectExpandClause;
writeContext.MetadataLevel = metadataLevel;
// Substitute stream to swap @odata.context
Stream substituteStream = new MemoryStream();
Stream originalStream = messageWriter.SubstituteResponseStream(substituteStream);
serializer.WriteObject(value, type, messageWriter, writeContext);
StreamReader reader = new StreamReader(substituteStream);
substituteStream.Seek(0, SeekOrigin.Begin);
JToken responsePayload = JToken.Parse(reader.ReadToEnd());
// If odata context is present, replace with odata metadata
if (responsePayload["@odata.context"] != null)
{
responsePayload["odata.metadata"] = responsePayload["@odata.context"].ToString().Replace("$entity", "@Element");
((JObject)responsePayload).Property("@odata.context").Remove();
}
// Write to actual stream
// We cannot dispose of the stream because this method does not own the stream (subsequent methods will close the streamwriter)
StreamWriter streamWriter = new StreamWriter(originalStream);
JsonTextWriter writer = new JsonTextWriter(streamWriter);
JsonSerializer jsonSerializer = new JsonSerializer();
jsonSerializer.Serialize(writer, responsePayload);
writer.Flush();
messageWriter.SubstituteResponseStream(originalStream);
}
}
