public static HttpQueryRequest CreateIntrospectionQuery(ISchemaFeatures features)
{
DocumentNode document = CreateIntrospectionQueryDocument(features);
string sourceText = QuerySyntaxSerializer.Serialize(document, false);
return(new HttpQueryRequest(sourceText, "introspection_phase_2"));
}
private static DocumentNode CreateIntrospectionQueryDocument(ISchemaFeatures features)
{
DocumentNode query = Utf8GraphQLParser.Parse(GetIntrospectionQuery());
OperationDefinitionNode operation =
query.Definitions.OfType <OperationDefinitionNode>().First();
FieldNode schema =
operation.SelectionSet.Selections.OfType <FieldNode>().First();
if (schema.SelectionSet is null)
{
throw new IntrospectionException();
}
FieldNode directives =
schema.SelectionSet.Selections.OfType <FieldNode>().First(t =>
t.Name.Value.Equals(_directivesField,
StringComparison.Ordinal));
if (directives.SelectionSet is null)
{
throw new IntrospectionException();
}
var selections = directives.SelectionSet.Selections.ToList();
AddDirectiveFeatures(features, selections);
FieldNode newField = directives.WithSelectionSet(
directives.SelectionSet.WithSelections(selections));
selections = schema.SelectionSet.Selections.ToList();
RemoveSubscriptionIfNotSupported(features, selections);
selections.Remove(directives);
selections.Add(newField);
newField = schema.WithSelectionSet(
schema.SelectionSet.WithSelections(selections));
selections = operation.SelectionSet.Selections.ToList();
selections.Remove(schema);
selections.Add(newField);
OperationDefinitionNode newOp = operation.WithSelectionSet(
operation.SelectionSet.WithSelections(selections));
var definitions = query.Definitions.ToList();
definitions.Remove(operation);
definitions.Insert(0, newOp);
return(query.WithDefinitions(definitions));
}
private static void RemoveSubscriptionIfNotSupported(
ISchemaFeatures features,
ICollection <ISelectionNode> selections)
{
if (!features.HasSubscriptionSupport)
{
FieldNode subscriptionField = selections.OfType <FieldNode>()
.First(t => t.Name.Value.Equals(_subscriptionType,
StringComparison.Ordinal));
selections.Remove(subscriptionField);
}
}
public async Task GetSchemaFeatures()
{
// arrange
TestServer server = CreateStarWarsServer();
var introspectionClient = new IntrospectionClient();
// act
ISchemaFeatures features =
await introspectionClient.GetSchemaFeaturesAsync(
server.CreateClient());
// assert
Assert.True(features.HasDirectiveLocations);
Assert.True(features.HasRepeatableDirectives);
Assert.True(features.HasSubscriptionSupport);
}
public async Task GetSchemaFeatures()
{
// arrange
TestServer server = CreateStarWarsServer();
HttpClient client = server.CreateClient();
client.BaseAddress = new Uri("http://localhost:5000/graphql");
var introspectionClient = new IntrospectionClient();
// act
ISchemaFeatures features = await introspectionClient.GetSchemaFeaturesAsync(client);
// assert
Assert.True(features.HasDirectiveLocations);
Assert.True(features.HasRepeatableDirectives);
Assert.True(features.HasSubscriptionSupport);
}
private static void AddDirectiveFeatures(
ISchemaFeatures features,
ICollection <ISelectionNode> selections)
{
if (features.HasDirectiveLocations)
{
selections.Add(CreateField(SchemaFeatures.Locations));
}
else
{
selections.Add(CreateField(_onField));
selections.Add(CreateField(_onFragment));
selections.Add(CreateField(_onOperation));
}
if (features.HasRepeatableDirectives)
{
selections.Add(CreateField(SchemaFeatures.IsRepeatable));
}
}
public async Task <DocumentNode> DownloadSchemaAsync(
HttpClient client,
CancellationToken cancellationToken = default)
{
if (client is null)
{
throw new ArgumentNullException(nameof(client));
}
ISchemaFeatures features = await GetSchemaFeaturesAsync(
client, cancellationToken)
.ConfigureAwait(false);
HttpQueryRequest request = IntrospectionQueryHelper.CreateIntrospectionQuery(features);
IntrospectionResult result = await ExecuteIntrospectionAsync(
client, request, cancellationToken)
.ConfigureAwait(false);
EnsureNoGraphQLErrors(result);
return(IntrospectionDeserializer.Deserialize(result).RemoveBuiltInTypes());
}
