You can achieve this in FME form with a traditional Reader (not a Feature Reader, not sure why Safe haven’t).

Select the format Esri ArcGIS Online (AGOL) Feature Service

Under the parameters of you should find this option… “include attachments”. Hopefully the latest FME form has this option on a featureReader, but last I checked… alas it did not

Then check the Format attributes and check on the agol attachments

This will expose it to the canvas. Not sure if it comes as a list, if so, then use ListExploder and from there you can use something like statisticsCalculator to count using a groupby on the ObjectID

https://support.safe.com/hc/en-us/articles/25407508005645-Writing-ArcGIS-Geodatabase-Attachments

Hi, that is exactly the approach I do not want to use as is very slow. I am thinking of using HTTP caller and JSON fragmenter as is faster

Previous articles all demonstrate Reader > expose list arcgis attachments > explode and counter

 HTTPcaller can use your existing web connection to AGOL and you can utilise the REST api documentation https://developers.arcgis.com/rest/services-reference/enterprise/query-attachments-feature-service-layer/

what am I doing wrong

Were you able to read the other articles, in one of the links you'll find an example

Read up on the generateToken page which is required to then queryAttachments.

1. Use an HTTPCaller to generate a token, then extract the token with a JSONFlattener or JSONFragmenter.
2. Merge the token onto the points
3. Query the feature service REST endpoint (ending with a number), e.g. https://gisweb.fortsask.ca/server/SERVICE_NAME/PARK_AMENITY/0/queryAttachments, where objectIds = objectid (from point)
4. JSONFragmenter to find the image URL
5. ImageFetcher @Value(URL)?token=@Value(token) to download the image