topic Re: Attachment URL with Token in Qt Maps SDK Questions

Attachment URL with Token

DavidPuckett — Sat, 04 Mar 2023 00:18:10 GMT

I have used the example in the attachments sample to 'manually' construct a url for an attachment

For unsecured services\attachments, I can set an Image source to this url successfully.
E.g.

const attachmentUrl = featureLayerUrl + "/" + oid + "/attachments/" + attachment.attachmentId

However, for secured services, constructing the url in this way and then appending the Credential token does not work.
E.g.

const attachmentUrl = featureLayerUrl + "/" + oid + "/attachments/" + attachment.attachmentId + "?token=" + app.portal.credential.token

The image status reports an Image.Error

onStatusChanged: if (thumbnail.status === Image.Error) workRecordThumbnail.source = "../assets/image-error.png"

The portal credential works to access the services (feature layers) but it seems I cannot simply append the credential token to the attachment url to view the attachment.

I am creating the Credential like this:

Credential { id: portalCredential oAuthClientInfo: OAuthClientInfo { oAuthMode: Enums.OAuthModeUser clientId: app.clientId } }

Any help?

Re: Attachment URL with Token

ZachBray — Mon, 06 Mar 2023 12:13:35 GMT

Have you tried including the f query parameter to your attachmentURL?

const attachmentUrl = featureLayerUrl + "/" + oid + "/attachments/" + attachment.attachmentId + "?f=json&token=" + app.portal.credential.token

Re: Attachment URL with Token

DavidPuckett — Mon, 06 Mar 2023 20:01:26 GMT

Thanks for the idea but it didn't resolve the issue. Still can't get to the attachment.

Re: Attachment URL with Token

JamesBallard1 — Mon, 06 Mar 2023 23:40:55 GMT

Hi @DavidPuckett,

Using the online map viewer and checking the network traffic, it looks like your url format is correct.

This is for OID=1, which only has one attachment (text file seen below).

Once you're logged in and have the token, if it's not working in the app I'd copy/paste that into the browser and see if that works.

Re: Attachment URL with Token

DavidPuckett — Tue, 07 Mar 2023 18:32:46 GMT

Pasting the url with the token from my app doesn't work either. I get an error from Web Adaptor saying 'Could not access any server machines. Please contact you system administrator'. So I guess the question is, why doesn't the token generated from the credential when a named user signs in work to get access to the attachments?

Re: Attachment URL with Token

ZachBray — Wed, 08 Mar 2023 13:23:05 GMT

I ran the following through Postman and got the image back. Where 209 is the Feature ObjectId and 144 is the attachment objectid from the attachments info endpoint, attachments. I had content type set to application/json

https://stingray.svec.coop/server/rest/services/SVEC/Workorker_GPS/FeatureServer/0/209/attachments/144?f=json&token=MyToken&w=100

Re: Attachment URL with Token

ZachBray — Wed, 08 Mar 2023 13:26:21 GMT

Forgot to mention, I added the w query parameter as referenced in the REST API docs.

https://developers.arcgis.com/rest/services-reference/enterprise/attachment-feature-service-.htm

Re: Attachment URL with Token

JamesBallard1 — Wed, 08 Mar 2023 17:12:04 GMT

@DavidPuckett I am not sure, unfortunately. There may be some additional level of complexity in your situation compared to what I've tested. If @ZachBray 's suggestions don't help, I recommend reaching out to support so we can further help you.

Re: Attachment URL with Token

DavidPuckett — Wed, 08 Mar 2023 19:33:49 GMT

@ZachBraythank you for this. So did you have an issue with using the url with a token as the source for an image? But using a Post worked for you? If so, I would be curious how you set the image source to the response from the Post request.

Re: Attachment URL with Token

DavidPuckett — Wed, 08 Mar 2023 19:36:34 GMT

I suspect you are right @JamesBallard1 We have a complex federated enterprise portal in place... thank you for the input.

I am curious if others have successfully used the attachment url with a token to display image attachments that are in secure portal environments however. Like, is this *supposed* to work ?! :collision:😎

Re: Attachment URL with Token

ZachBray — Wed, 08 Mar 2023 22:00:35 GMT

I was able to copy and paste the url string from Postman with a recent token value into a Chrome browser window and get the attachment. We have a federated Portal, Server setup as well. I got my token through https://my_webadapter_server/portal/sharing/rest/generateToken. I supplied a username, password, client = referer, f=json, referer=https://my_webadapter_server/server as the form body.

Hope this helps.

Re: Attachment URL with Token

DavidPuckett — Thu, 09 Mar 2023 19:16:38 GMT

So I created a QML NetworkRequest that I used to POST a request using the url to the attachment image and passing the token, f:json and referer into the request. I got back the same web adaptor error, as html 😔 Thanks for the suggestions again @ZachBray but I'm afraid there is something happening with the token that is being generated. I remain open to ideas however...

Re: Attachment URL with Token

ZachBray — Thu, 09 Mar 2023 22:02:33 GMT

I was using the generateToken endpoint and it looks like you are using the oauth2 endpoint. I was able to get an access_token using .../rest/oauth2/authorize?client_id=????&response_type=token&redirect_uri=????. I could then copy paste the access_token into my same attachments request in a Chrome browser Window and get the image back. So I would think that this should work.

Your error message indicated that it could not find any server machines. Is there any potential networking issues, your machine not able to get to the server? Was the Feature Service you are working with published with attachments enabled? Are you able to access the attachment through another method, I confirmed mine through ArcGIS Pro and by making an attachments info call which is just .../FeatureServer/layer_id/objectId/attachments. The attachments info call is where I got the attachment object id I need to get the actual image back. Can you return just your expected access_token so that you could copy it into a browser window to confirm it is valid?

Just throwing out somethings that might jog your memory. I was able to make this work in my environment, so you should be able to as well.

Good luck.