How to retrieve custom field image files?

Question

How can I retrieve images uploaded in custom field sets for contacts? Could you get a URL for them the same way you can for the contact "image_url" in the API?

When I look up the custom field for the file in the API, it just returns a number. I looked at the code docs for the Attachment entity in the API, but this seems to be more suited for non-image files, unless I'm mistaken. I am looking to call the API and display these images on a web page.

I'd appreciate any help I can get, thanks.

Answer 1

Without more context about what the API call you're making is, I can't say why it just returns a number. Here's what happens when I call the API from my command line to get the results of the attachment with an ID of 1:

» cv api attachment.get id=1
{
    "is_error": 0,
    "version": 3,
    "count": 1,
    "id": 1,
    "values": {
        "1": {
            "id": "1",
            "name": "Project_Properties_dmaster_677.png",
            "mime_type": "image/png",
            "description": "",
            "upload_date": "2018-11-27 22:19:47",
            "entity_table": "civicrm_activity",
            "entity_id": "628",
            "icon": "fa-file-image-o",
            "created_id": "",
            "url": "http://dmaster.localhost/civicrm/file?reset=1&id=1&eid=628",
            "path": "/home/jon/local/civicrm-buildkit/build/dmaster/sites/default/files/civicrm/custom//Project_Properties_dmaster_677_ab277eebda5f50aeb9910018ab356f34.png"
        }
    }
}

It returns the URL property which I can output in an HTML file within an <img> tag to display the image on a web page.