GraphiQL on Orchard-Core: "where" and "filter" does not work - orchardcms

Question

I am trying to understand how to query with GraphiQL on Orchard-Core and I am facing some problems which I cannot fix:
I am trying to implement an extremelly simple query:
query MyQuery ($myDesc: String) {
product (where: {description: $myDesc}) {
description
}
}
When I try to play the query I receive the following error:
{
"errors": [
{
"message": "Argument \"where\" has invalid value {description: $myDesc}.\nIn field \"description\": Unknown field.",
"locations": [
{
"line": 17,
"column": 11
}
],
"extensions": {
"code": "5.3.3.1"
}
}
]
}
It says that 'Field "description" is not defined by type "productWhereInput"'
I need to apply to the products a bunch of filters to give me the result I want, but none of them are working.
I have also tried to use "filter" instead of "where", but then I get another error:
'Unknown argument "filter" on field "Query.product".'
Looking to some documentations it doesn't seem to be so hard to use GraphiQL, but when I try to write the code in the way I find it on the docs it give me errors after errors here on Orchard-Core.

Answer 1

There are only limited number of default implemented where filters. By the error you get you didn't implement WhereInputObjectGraphType for your part.
One way is to create yessql MapIndex on fields you want to be able to query.
I'll assume Description is TextField.
So first create ProductPartIndex class as YesSQL MapIndex, that will map Description of every ContentItem with ProductPart.
After that you need to connect index with GraphQL WhereInputObjectType.
public class ProductInputObjectType : WhereInputObjectGraphType<ProductPart>
{
public ProductInputObjectType(IStringLocalizer<ProductInputObjectType> S)
{
AddScalarFilterFields<StringGraphType>("description", S["product description"]);
}
}
public class ProductPartIndexAliasProvider : IIndexAliasProvider
{
private static readonly IndexAlias[] _aliases = new[]
{
new IndexAlias
{
Alias = "ProductPart",
Index = nameof(ProductPartIndex),
IndexType = typeof(ProductPartIndex)
}
};
public IEnumerable<IndexAlias> GetAliases()
{
return _aliases;
}
}
[RequireFeatures("OrchardCore.Apis.GraphQL")]
public class Startup : StartupBase
{
public override void ConfigureServices(IServiceCollection services)
{
services.AddInputObjectGraphType<ProductPart, ProductInputObjectType>();
services.AddTransient<IIndexAliasProvider, ProductPartIndexAliasProvider>();
services.AddWhereInputIndexPropertyProvider<ProductPartIndex>();
}
}
This is adhoc code, didn't test it. Everything in here is altered version of AliasPart from source code.