public async Task InvokeAsync(IMiddlewareContext context)
{
DelegateDirective delegateDirective = context.Field
.Directives[DirectiveNames.Delegate]
.FirstOrDefault()?.ToObject <DelegateDirective>();
if (delegateDirective != null)
{
IImmutableStack <SelectionPathComponent> path =
delegateDirective.Path is null
? ImmutableStack <SelectionPathComponent> .Empty
: SelectionPathParser.Parse(delegateDirective.Path);
IReadOnlyQueryRequest request =
CreateQuery(context, delegateDirective.Schema, path);
IReadOnlyQueryResult result = await ExecuteQueryAsync(
context, request, delegateDirective.Schema)
.ConfigureAwait(false);
UpdateContextData(context, result, delegateDirective);
context.Result = new SerializedData(
ExtractData(result.Data, path.Count()));
ReportErrors(context, result.Errors);
}
await _next.Invoke(context).ConfigureAwait(false);
}
private void UpdateContextData(
IResolverContext context,
IReadOnlyQueryResult result,
DelegateDirective delegateDirective)
{
if (result.ContextData.Count > 0)
{
ImmutableDictionary <string, object> .Builder builder =
ImmutableDictionary.CreateBuilder <string, object>();
builder.AddRange(context.ScopedContextData);
builder[WellKnownProperties.SchemaName] = delegateDirective.Schema;
builder.AddRange(result.ContextData);
context.ScopedContextData = builder.ToImmutableDictionary();
}
else
{
context.ModifyScopedContext(c => c.SetItem(
WellKnownProperties.SchemaName,
delegateDirective.Schema));
}
}