Whenever I update a field in the schema, the screen gets stuck on loading. Leaving the item, and coming back shows it updated, so the update does work. Happens on all models, as far as I can tell.
The PUT request to https://site-api.datocms.com/fields/:fieldId gets 202. I see no additional failed requests either.
Edit: There are people on my team who donāt experience it. Not sure if anyone else does.
Hi @thiago,
Hmm, thatās really strange. Does this happen only one particular project for you (like is it the same if you make a free demo project from a starter in your personal account)?
For troubleshooting, could we please try one or both of these:
Is it ok I try to replicate this in your project, either in a new test model or in a forked sandbox environment?
And/or could you please provide a screen recording of this happening, with browser console open and āLogXMLHttpRequestsā enabled?
Basically, Iām trying to see if this is an issue with a particular project (possibly a plugin?), a browser, a network issue, etc.
Thank you!
Edit: Also, super quick thing to test: Sometimes these are just stale browser files in the cache. If you log out of DatoCMS, hard refresh your browser, and then log back in, does this still happen? Or in an Incognito window?
I am experiencing the same error, or a similar one at least. My console shows the following errors:
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://site-api.datocms.com/editing-sessions/cm615rmq200002e6fs9tyahqz. (Reason: CORS request did not succeed). Status code: (null).
Uncaught (in promise) TypeError: NetworkError when attempting to fetch resource.
Uncaught (in promise) TypeError: t.itemType is undefined
UNSAFE_componentWillReceiveProps https://assets.admin.datocms.com/build/index-VBJUQST4.js:181
index-VBJUQST4.js:181:115337
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://site-api.datocms.com/pusher/authenticate. (Reason: CORS request did not succeed). Status code: (null).
Using Firefox with a VPN. It seems to happen to me more often when I have left the editor tab open for a while and then try to make a change.
Edit: Just had another hangup when trying to create a new structured text field on a block record. However, reloading the page shows that the API request actually was successful, and the field existed on the reloaded page.
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://internal.datocms.com/ui/version/542eb00e7/check. (Reason: CORS request did not succeed). Status code: (null).
Uncaught (in promise) TypeError: NetworkError when attempting to fetch resource.
Uncaught (in promise)
Object { data: (1) [ā¦], reqResMeta: {ā¦}, error: Error }
data: Array [ {ā¦} ]
0: Object { id: "302048", type: "api_error", attributes: {ā¦} }
attributes: Object { code: "NOT_FOUND", details: {} }
id: "302048"
type: "api_error"
<prototype>: Object { ā¦ }
length: 1
<prototype>: Array []
error: Error: Failed API call https://site-api.datocms.com/item-types/new
columnNumber: 108263
fileName: "https://assets.admin.datocms.com/build/chunk-GVUZS262.js"
lineNumber: 1
message: "Failed API call https://site-api.datocms.com/item-types/new"
stack: "Cu@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:108263\nPu@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:108394\nUr/<@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:109343\nRS/<@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:109675\nGf@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:112999\nIe/i/<@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:121285\nHA/t/</<@https://assets.admin.datocms.com/build/chunk-RPQW2TL3.js:7:6227\ncomponentDidMount@https://assets.admin.datocms.com/build/index-VBJUQST4.js:181:114915\nLm@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:11:1673\nIm@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:13:5037\nra</L.unstable_runWithPriority@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:5:6705\nEt@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:9:38466\npt@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:13:1813\nnu@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:11:11095\nYc</pc/<@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:9:38688\nra</L.unstable_runWithPriority@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:5:6705\nEt@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:9:38466\npc@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:9:38636\nMe@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:9:38569\nIc@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:11:11307\nnotify@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:1:1274\nl@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:1:1653\ni@https://assets.admin.datocms.com/build/chunk-2QH7ANLE.js:1:1694\nm@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:160713\nFA</yW/</<@https://assets.admin.datocms.com/build/chunk-RPQW2TL3.js:7:3291\nBA</CW/</<@https://assets.admin.datocms.com/build/chunk-RPQW2TL3.js:7:3689\nBh/</<@https://assets.admin.datocms.com/build/chunk-RPQW2TL3.js:7:30788\nHA/t/</<@https://assets.admin.datocms.com/build/chunk-RPQW2TL3.js:7:6236\ndispatch@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:164453\nIe/i/<@https://assets.admin.datocms.com/build/chunk-GVUZS262.js:1:121301\n"
<prototype>: Error.prototype { stack: "", ā¦ }
reqResMeta: Object { request: {ā¦}, response: {ā¦} }
request: Object { url: "https://site-api.datocms.com/item-types/new", headers: {ā¦} }
headers: Object { "X-Site-Domain": "[SITE_NAME].admin.datocms.com", "Content-Type": "application/json", Accept: "application/vnd.api+json", ā¦ }
Accept: "application/vnd.api+json"
Authorization: "Bearer [TOKEN]"
"Content-Type": "application/json"
"X-Api-Version": "3"
"X-Environment": "[ENV_NAME]"
"X-Site-Domain": "[SITE_NAME].admin.datocms.com"
<prototype>: Object { ā¦ }
url: "https://site-api.datocms.com/item-types/new"
<prototype>: Object { ā¦ }
response: Object { status: 404, headers: {ā¦} }
Hey @clay1,
Does this still happen without the VPN on, or with a different browser?
Weāve noticed that some VPNs or enterprise security software will sometimes intercept our requests as a man-in-the-middle and then incorrectly rewrite our CORS headers into something invalid. If that happens, many of our endpoints will break.
The endpoint https://site-api.datocms.com/editing-sessions/ should not have a same-origin policy, for example. It should dynamically return your project URL the access-control-allow-origin.
e.g. from this CORS tester:
As a quick and dirty test, you can also try a CORS unblocking extension like https://addons.mozilla.org/en-US/firefox/addon/cors-everywhere/ to see if that makes a difference (that addon is not affiliated with us; itās just an example)
Might that be whatās going on?
@roger I have not noticed it happening when the VPN is disconnected, so that seems like a likely culprit. Iāll try the extension and see if I can duplicate the error.
Thank you @clay1. Can I ask which VPN or app it is? This is not standard web behavior (VPNs shouldnāt be rewriting headers like that, because that can break our site and others). But itās also not the first time weāve heard of this happening 
If I can look into their implementation and better understand why & how they do this, maybe we can see if thereās something we can do on our side to make it more resilient.
Hmm, I wonder if itās because we generate the CORS dynamically, and maybe the VPN is stripping out some origin stuff as a privacy measure?
@roger I am using Surfshark, and I had rotating IP enabled (changes every 5 mins or so) as well if that makes any difference.
Bummer, I canāt test that without a paid subscription, and their docs donāt have any details that I could find 
Only if you have time and want to help further troubleshoot thisā¦ can you open the network inspector and Firefox (before you install that CORS extension), with the VPN enabled, and see what itās trying to send to us, especially the āoriginā field?
And also what the response says?
You can also right-click the response and āSave all as HARā and email that file to us at support@datocms.com if you prefer (itās just a request/response capture, so we can see what exactly your browser is sending and receiving through the VPN).
If I can figure out specifically whatās happening, I will let the devs know and hopefully we can make a workaround 
But if itās too much effort, np, just turning off the VPN and/or the extension will hopefully help. Up to you! (But thank you for the details either way)
@roger I was able to replicate again. It seems to only happen if Iāve let the page idle for a while. The only thing that I can see in these requests that is different from the previous successful ones is that the address here is undefined instead of 104.22.2.171:443.
POST /pusher/authenticate undefined
Host: site-api.datocms.com
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:134.0) Gecko/20100101 Firefox/134.0
Accept: application/json
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate, br, zstd
Content-Type: application/x-www-form-urlencoded, application/json
Authorization: Bearer [TOKEN]
X-Api-Version: 3
X-Site-Domain: [SITE_NAME].admin.datocms.com
Content-Length: 78
Origin: https://[SITE_NAME].admin.datocms.com
Connection: keep-alive
Referer: https://[SITE_NAME].admin.datocms.com/
Sec-Fetch-Dest: empty
Sec-Fetch-Mode: cors
Sec-Fetch-Site: same-site
DNT: 1
Sec-GPC: 1
GET /ui/version/7188365fa/check undefined
Host: internal.datocms.com
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:134.0) Gecko/20100101 Firefox/134.0
Accept: */*
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate, br, zstd
Referer: https://[SITE_NAME].admin.datocms.com/
Origin: https://[SITE_NAME].admin.datocms.com
Connection: keep-alive
Sec-Fetch-Dest: empty
Sec-Fetch-Mode: cors
Sec-Fetch-Site: same-site
DNT: 1
Sec-GPC: 1
Priority: u=4
TE: trailers
Was that with the VPN already disabled?
Do you have any sort of other privacy software running, especially anything that might provide custom DNS?
That was with the VPN enabled. But I just realized I have Privacy Badger running as well, which is more likely the cause. I will try disabling for the day and see if I run into the issue again.
Edit: Privacy Badger was blocking cookies from ws-mt1.pusher.com
Edit 2: Had the same error again, with all browser plugins disabled.
POST /items/191949471/validate undefined
Host: site-api.datocms.com
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:134.0) Gecko/20100101 Firefox/134.0
Accept: application/vnd.api+json
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate, br, zstd
Referer: https://[SITE_NAME].admin.datocms.com/
X-Site-Domain: [SITE_NAME].admin.datocms.com
Content-Type: application/json
X-Api-Version: 3
Authorization: Bearer [TOKEN]
X-Environment: [ENV]
X-Session-Id: cm685a4gp00002e6fm06it7tu
Content-Length: 841
Origin: https://[SITE_NAME].admin.datocms.com
Connection: keep-alive
Sec-Fetch-Dest: empty
Sec-Fetch-Mode: cors
Sec-Fetch-Site: same-site
Priority: u=4
TE: trailers
Was the VPN also a āpluginā, or is that still on?
POST /items/191949471/validate undefined
Sorry, what am I looking at here? Are those the request headers being sent? What was the response?
Iām sorry for the continued hassle, but could you please save the entire roundtrip as an .HAR file and send that to me (I need to be able to see all the back and forth)? In the network inspector, find the failing request(s), right click and choose āSave all as .HARā. You can email that to r.tuan@datocms.com.
Iāve tried to reproduce it on my own but cannot so far, so I suspect itās something particular to your configuration or network. Being able to see the network traffic would help diagnose it.
Edit: And just to be clear, only do this if itās still causing an issue for you! If you managed to work around it, donāt feel like you have to help us keep troubleshooting this forever