Sharepoint Online REST strange error (400)

[slavag]

Category

• Bug

Describe the bug

Since Sep 9, 2020 we started to get strange error on REST API call to get list of sub-sites and their lists:

GET <site url>_api/web?$expand=webs,lists,AllProperties,ThemeInfo,SiteUsers,RoleDefinitions&$select=*,webs/Url,lists/Id,lists/Title,lists/Description,lists/BaseType,lists/BaseTemplate,lists/Hidden,lists/Language,lists/ItemCount,lists/Created,lists/TemplateFeatureId,lists/CurrentChangeToken,SiteUsers/id,SiteUsers/Title,SiteUsers/LoginName,AllProperties/DesignPreviewThemedCssFolderUrl

The API call was working already for few year but something is broken now and in many our customers (not all , but few thousands of Sharepoint online tenants) we see this error.

{"error":{"code":"-2147467261, System.ArgumentNullException","message":{"lang":"en-US","value":"Value cannot be null.Parameter name: key"}}}

Now, we don't ask for any parameter "key", so not sure why it's null, but I found that if I remove the last part
AllProperties/DesignPreviewThemedCssFolderUrl
And request now looks :

GET <site url>_api/web?$expand=webs,lists,AllProperties,ThemeInfo,SiteUsers,RoleDefinitions&$select=*,webs/Url,lists/Id,lists/Title,lists/Description,lists/BaseType,lists/BaseTemplate,lists/Hidden,lists/Language,lists/ItemCount,lists/Created,lists/TemplateFeatureId,lists/CurrentChangeToken,SiteUsers/id,SiteUsers/Title,SiteUsers/LoginName

Then this request is returns fine, without any error

Expected behavior

GET <site url>_api/web?$expand=webs,lists,AllProperties,ThemeInfo,SiteUsers,RoleDefinitions&$select=*,webs/Url,lists/Id,lists/Title,lists/Description,lists/BaseType,lists/BaseTemplate,lists/Hidden,lists/Language,lists/ItemCount,lists/Created,lists/TemplateFeatureId,lists/CurrentChangeToken,SiteUsers/id,SiteUsers/Title,SiteUsers/LoginName,AllProperties/DesignPreviewThemedCssFolderUrl

The original API call should not return that error, or at least notifies how it can be resolved.

Environment details (development & target environment)

MacOS / Linux. Postman as well.

Additional context

This API call was working for few years without any issue (once we got Invalid color XML error, on that call).

Thanks
Please advise.

[msft-github-bot]

Thank you for reporting this issue. We will be triaging your incoming issue as soon as possible.

[rjaakke]

Same issue in CSOM when trying to load ThemeInfo on SPWeb.

SpContext.Load(spWeb, o => o.ThemeInfo);
SpContext.ExecuteQuery();

[bcameron1231]

Some additional Information to add for triage -

This may be a tenant by tenant issue... as this call is working for me on my tenants.

[slavag]

This happens not for all tenants, but I would say for our customers , it's hundreds and hundreds. And even in our private tenant is also happens. I can share tenant id in private if it's needed.
Thanks

[slavag]

@microsoft - Any progress on this ? Seems that many have this issue : bramdejager/spcb#98

[bramdejager]

I validated some conditions because I'm experiencing this on different tenants, but not all. Server/farm versions are all identical for both the ones working and not working.

@rjaakke it seems it is not connected to a particular property or object. You experienced this with ThemeInfo and in the SPCB tool it triggered with Site.RootWeb.CurrentUser it seems. And if I leave out this check, then the next statement is on the Web will trigger the error.

Clearly the issue came up after September 9th. See timeline of the issues below.

[slavag]

In my case it REST call, started on Sep 9 as well, but I did a workaround , removed AllProperties/DesignPreviewThemedCssFolderUrl from the select statement

[rjaakke]

@bramdejager In our Provisioning tool we load a large portion of the available properties (that have a setter) in a single call.
The ThemeInfo object is wat caused the issue there. Because we only needed themeBackgroundImageUri from the ThemeInfo object we now load ThemeInfo.ThemeBackgroundImageUri instead and it solved the issue.

It could be that this is somehow related to expanding of objects in the API. This would explain why we see this issue loading different types of objects.