how does publishing works with ECL item when using template less publishing, does it include ecl external metadata as well

Question

When publishing a page having component with ecl item attached. it publishes successfully. adding screenshot of page and component for reference

component:

when checking response on graphql it doesn't add details for multimedia field when using typeContent graphql query

"components": [
            {
                "itemId": 1046,
                "title": "Basic",
                "media": null
            }
        ]

and when using untyped content query it given ecl id as title on multimedia link

"components": [
            {
                "itemId": 1046,
                "title": "Basic",
                "content": {
                    "id": null,
                    "type": null,
                    "__typename": "UntypedContent",
                    "data": {
                        "$type": "Fields",
                        "title": "Test",
                        "media": {
                            "$type": "Link",
                            "id": "tcm:XXX-XXXX",
                            "title": "ecl:0-sam-Calendar.jpg-SAMFile-file"
                        }
                    }
                }
            }
        ]

I need to retrieve metadata of ecl multimedia item, please suggest how could we achieve the same.

Answer 1

Frankly, I'm not sure about the GraphQL side of the story (where your question seems mostly about), but on CM side, there is a specific data pipeline model for ECL items:

public class ExternalContentLibraryModel : ComponentModel, IExternalComponent
{
    public string ExternalUri { get; set; }
    public IFields ExternalMetadata { get; set; }
    public ILink ExternalSchema { get; set; }
    public ISchema ExternalSchemaData { get; set; }
}

As you can see, it's an extension of the standard ComponentModel and adds ECL-specific information. Besides these additional properties, ECL also sets some of the ComponentModel properties, so it reflects the ECL item. For example: it sets ComponentModel.Binaries to a BinaryModel with Url reflecting the ECL Direct Link To Published (if available).

These data pipeline models get serialized to JSON and that's what's sent to Content Delivery.