GraphQL ProductFilterInput Requires Field to be a String

[maxbucknell]

Every field of the ProductFilterInput input field in Magento_CatagolGraphQl::etc/graphql.xml has the type FilterTypeInput. The problem here is that FilterTypeInput requires most of its arguments to be strings.

For example, I might want to select products that do not have a special price set. This might be some query like:

{
  products(filter: { special_price: { null: true } }) {
    total_count
  }
}

The devdocs, and basic intuition seem to suggest this is okay. However, this doesn't work because Magento_GraphQl::etc/graphql.xml requires the null field in FilterTypeInput to be a string.

Preconditions

1. This is GraphQL, so it's in 2.3-develop, natch.

Steps to reproduce

1. Try to submit the query written above.

Expected result

Based on the documentation, I would expect this to be a legal query.

Receive a response like this:

{
  "data": {
    "products": {
      "total_count": 0
    }
  }
}

Actual result

Response:

{
  "errors": [
    {
      "message": "Argument \"filter\" has invalid value {special_price: {null: true}}.\nIn field \"special_price\": In field \"null\": Expected type \"String\", found true.",
      "category": "graphql",
      "locations": [
        {
          "line": 2,
          "column": 20
        }
      ]
    }
  ]
}

This also applies to other fields. For example, I was unable to filter products by category ids.

[maxbucknell]

After some research, I have found that this isn't what is causing this particular issue. While there is an issue with using the same FilterTypeInput field and requiring all fields to be a String, this particular issue is caused by /issues/14355, and I will fix that.

I believe that the FilterTypeInput issue does require further discussion, though.

[misha-kotov]

Hey @maxbucknell since the root cause is described in the other ticket, can we close this issue? We can discuss FilterTypeInput in slack or offline

[magento-engcom-team]

Hi @maxbucknell. Thank you for your report.
The issue has been fixed in #14356 by @maxbucknell in 2.3-develop branch
Related commit(s):

• 7a3ea4ef23584d3dfdd1f414dad69858c3c46ac9
• 4589cb0ad644290e5e8d968b275bc5e2357bb349

The fix will be available with the upcoming 2.3.0 release.