/// <summary>
/// Accept a V3 request URI and return a V4 request URI. V4 request URI retains base path.
/// </summary>
/// <param name="requestUri">V3 Request URI</param>
/// <returns>V4 Request URI</returns>
public Uri TranslateUri(Uri requestUri)
{
// Use UriTranslator to walk v3 segments, translating each to v4 and returning.
ODataPath v3path = new ODataUriParser(this.v3Model, this.serviceRoot).ParsePath(requestUri);
UriSegmentTranslator uriTranslator = new UriSegmentTranslator(this.v4Model);
Microsoft.OData.UriParser.ODataPath v4path = new Microsoft.OData.UriParser.ODataPath(v3path.WalkWith(uriTranslator));
// Parse query options for translation
NameValueCollection requestQuery = HttpUtility.ParseQueryString(requestUri.Query);
// Create a v4 ODataUri and utilized ODataUriExtensions methods to build v4 URI
ODataUri v4Uri = new ODataUri()
{
Path = v4path,
Filter = ParseFilterFromQueryOrNull(requestQuery, v4path, v3path)
};
Uri v4RelativeUri = ODataUriExtensions.BuildUri(v4Uri, ODataUrlKeyDelimiter.Parentheses);
Uri v4FullUri = new Uri(serviceRoot, v4RelativeUri);
// Translated query only contains translated filter clause
// We need to move everything from v3 query that does not require translation to v4 query
NameValueCollection translatedQuery = HttpUtility.ParseQueryString(v4FullUri.Query);
// Copy values from requestQuery to new translated query. Iterate with multiple loops
// because NameValueCollections also support multiple values to one key
foreach (string k in requestQuery)
{
foreach (string v in requestQuery.GetValues(k))
{
string key = k.Trim();
if (key == "$inlinecount")
{
translatedQuery["$count"] = ParseInlineCountFromQuery(v.Trim());
}
else if (key != "$filter")
{
translatedQuery[k] = v;
}
}
}
UriBuilder builder = new UriBuilder(serviceRoot.Scheme, serviceRoot.Host, serviceRoot.Port, v4FullUri.AbsolutePath);
// NameValueCollection ToString is overriden to produce a URL-encoded string, decode it to maintain consistency
builder.Query = WebUtility.UrlDecode(translatedQuery.ToString());
return(builder.Uri);
}
// new, ok
private ODataQueryContext GetQueryContext(Type rootType, Type entityType)
{
MakeModel(rootType);
//var entitySet = _model.FindDeclaredEntitySet(rootType.Name);
var segment = new Microsoft.OData.UriParser.PathTemplateSegment($"~/"); // {rootType.Name}
var path = new ODataPath(segment);
var uriParseODataPath = new Microsoft.OData.UriParser.ODataPath(segment);
var queryContext = new ODataQueryContext(_model, entityType, path)
{
DefaultQuerySettings =
{
EnableCount = true,
EnableExpand = true,
EnableFilter = true,
EnableOrderBy = true,
EnableSelect = true,
//MaxTop = 100,
},
};
return(queryContext);
}
// If filter clause is found in query, translate from v3 filter clause to v4 clause
private Microsoft.OData.UriParser.FilterClause ParseFilterFromQueryOrNull(NameValueCollection query, Microsoft.OData.UriParser.ODataPath pathSegments, ODataPath v3Segments)
{
Microsoft.OData.UriParser.FilterClause v4FilterClause = null;
// The MSDN specification advises checking if NameValueCollection contains key by using indexing
// https://docs.microsoft.com/en-us/dotnet/api/system.collections.specialized.namevaluecollection.item?redirectedfrom=MSDN&view=netframework-4.8#System_Collections_Specialized_NameValueCollection_Item_System_String_
if (query["$filter"] != null)
{
// Parse filter clause in v3
EntitySetSegment entitySegment = v3Segments.Reverse().FirstOrDefault(segment => segment is EntitySetSegment) as EntitySetSegment;
Data.Edm.IEdmEntityType entityType = entitySegment.EntitySet.ElementType;
FilterClause v3FilterClause = ODataUriParser.ParseFilter(query["$filter"], v3Model, entityType);
// Translate node and range variable into v4 format
QueryNodeTranslator queryTranslator = new QueryNodeTranslator(v4Model);
Microsoft.OData.UriParser.SingleValueNode v4Node = (Microsoft.OData.UriParser.SingleValueNode)v3FilterClause.Expression.Accept(queryTranslator);
Microsoft.OData.UriParser.RangeVariable v4Var = queryTranslator.TranslateRangeVariable(v3FilterClause.RangeVariable);
v4FilterClause = new Microsoft.OData.UriParser.FilterClause(v4Node, v4Var);
}
return(v4FilterClause);
}
