Fetch with include

article.json

{
	"data": {
    ...
		"relationships": {
      ...
			"field_image": {
				"data": {
					"type": "file--file",
					"id": "ff50dc33-175e-4b19-ab2a-82220fa7f022",
					"meta": {
						"alt": "Aptent at blandit humo ille interdico macto saepius sino vereor.",
						"title": "Appellatio humo singularis. Comis dignissim jus luctus nostrud odio premo voco.",
						"width": "521",
						"height": "420"
					}
				},
				"links": {
					"self": "http:\/\/drupal.docker.localhost:8000\/jsonapi\/node\/article\/6c50cb76-fcd1-4e71-b987-2de6d4cdcbc4\/relationships\/field_image",
					"related": "http:\/\/drupal.docker.localhost:8000\/jsonapi\/node\/article\/6c50cb76-fcd1-4e71-b987-2de6d4cdcbc4\/field_image"
				}
			},
      ...
		},
		"links": {
			"self": "http:\/\/drupal.docker.localhost:8000\/jsonapi\/node\/article\/6c50cb76-fcd1-4e71-b987-2de6d4cdcbc4"
		}
	},
	"jsonapi": {
    ...
	},
	"links": {
    ...
	},
	"included": [
		{
			"type": "file--file",
			"id": "ff50dc33-175e-4b19-ab2a-82220fa7f022",
			"attributes": {
				"fid": 28,
				"uuid": "ff50dc33-175e-4b19-ab2a-82220fa7f022",
				"langcode": "en",
				"filename": "generateImage_BPmlnl.png",
				"uri": "public:\/\/2018-01\/generateImage_BPmlnl.png",
				"filemime": "image\/png",
				"filesize": 2456,
				"status": true,
				"created": 1514982134,
				"changed": 1514982134,
				"url": "\/sites\/default\/files\/2018-01\/generateImage_BPmlnl.png"
			},
			"relationships": {
				"uid": {
					"data": {
						"type": "user--user",
						"id": "a2602c02-a84b-4e34-b34e-69b82214c377"
					},
					"links": {
						"self": "http:\/\/drupal.docker.localhost:8000\/jsonapi\/file\/file\/ff50dc33-175e-4b19-ab2a-82220fa7f022\/relationships\/uid",
						"related": "http:\/\/drupal.docker.localhost:8000\/jsonapi\/file\/file\/ff50dc33-175e-4b19-ab2a-82220fa7f022\/uid"
					}
				}
			},
			"links": {
				"self": "http:\/\/drupal.docker.localhost:8000\/jsonapi\/file\/file\/ff50dc33-175e-4b19-ab2a-82220fa7f022"
			}
		}
	]
}