Frontmatter list items not treated as Files

[dustinhorton]

(Originally raised @ #780 (comment), but think it may have been missed, so wanted to make a fresh issue).

Using 1.9.83:

Markdown frontmatter list:

images:
  - ./images/01.jpg
  - ./images/02.jpg
  - ./images/03.jpg

Query:

{
  markdownRemark {
    frontmatter {
      images
    }
  }
}

Result:

{
  "data": {
    "markdownRemark": {
      "frontmatter": {
        "images": [
          "./images/01.jpg",
          "./images/02.jpg",
          "./images/03.jpg"
        ]
      }
    }
  }
}

And if trying to treat as Files:

{
  markdownRemark {
    frontmatter {
      images {
        childImageSharp {
          responsiveSizes {
            src
          }
        }
      }
    }
  }
}

Result:

{
  "errors": [
    {
      "message": "Field \"images\" must not have a selection since type \"[String]\" has no subfields.",
      "locations": [
        {
          "line": 4,
          "column": 14
        }
      ]
    }
  ]
}

[KyleAMathews]

Can you build a reproduction site? There's been several PRs addressing this recently so not sure what's wrong.

[dustinhorton]

@KyleAMathews Give this a shot: https://github.com/dustinhorton/gatsby-issue

It's the blog starter, and I've modified the 'New Beginnings'/'/hi-folks/' post. Not sure that was an optimal repro…let me know if I can provide something better.

[KyleAMathews]

The images have to exist for the link to be created.

[dustinhorton]

@KyleAMathews Apologies, I'd forgotten to git add after adding them to the repro site. I've added them: https://github.com/dustinhorton/gatsby-issue/commit/fddf025b84c1889f2afdfa92c51ff9419e3c77f3

[KyleAMathews]

Ok, found the source of the bug. For our GraphQL inference, we have a general type inference and then we do special mappings for manual mappings, the ___NODE syntax, and file mappings. We're not looking inside arrays right now for file mappings. I'll put together a quick PR for that.

Thanks @dustinhorton for the repo site! Always super helpful to have those when debugging.

[owenhoskins]

Hello @KyleAMathews, I was wondering if this addresses a nested list within a list?

I am getting this error GraphQL Error Field "image" must not have a selection since type "String" has no subfields. with this in my frontmatter:

portfolios:
  - images:
      - image: /img/image1.jpg
  - images:
      - image: /img/image2.jpg

Images within a top-level list behave as expected. Could this be related?

[KyleAMathews]

@owenhoskins try not repeating your keys (you have two images) and see if it starts working?

[owenhoskins]

@KyleAMathews Thanks for the reply. It turns out the repeating keys were not the issue! Rather I had a onCreateNode API function that was throwing off the file system.

[justinlevi]

I recently had an odd issue with the Type inference not working with what seemed like some reserved keys. I had a header key with an image path that the auto-inference didn't seem to like.