SharePoint Online Site Page: Cannot expand canvasLayout on baseSitePage (HTTP status 400)

[heinrich-ulbricht]

What's the goal?

Retrieve a SharePoint Online modern page via Microsoft Graph, using the beta endpoint, using the MS Graph Beta SDK. The page should be returned with content.

How is it failing?

Retrieving a site page (microsoft.graph.sitePage) via Pages returns just a base site page (microsoft.graph.baseSitePage), making it impossible to expand e.g. the canvasLayout property.

Here's how I'm retrieving the page, trying to expand canvasLayout:

var sitePage = await graphClient
    .Sites[siteId]
    .Pages[pageId]
    .GetAsync(config =>
    {
        config.QueryParameters.Expand = new[] { "canvasLayout" };
    }) as SitePage;

This throws the exception Parsing OData Select and Expand failed: Could not find a property named 'CanvasLayout' on type 'microsoft.graph.baseSitePage'.

Looking at the generated request I see this:

https://graph.microsoft.com/beta/sites/_siteid_/pages/_pageId_?$expand=canvasLayout

But this should rather be:

https://graph.microsoft.com/beta/sites/_siteid_/pages/_pageId_/microsoft.graph.sitePage?$expand=canvasLayout

How to achieve this, using the Graph Client SDK?

Used for testing:

• latest Graph Beta SDK from Nuget (v5.59.0-preview)
• Windows 11
• .NET 6

[heinrich-ulbricht]

One workaround is:

var graphPageRequest = graphClient
    .Sites[siteId]
    .Pages[pageId]
    .ToGetRequestInformation();
graphPageRequest.UrlTemplate = $"{{+baseurl}}/sites/{siteId}/pages/{pageId}/microsoft.graph.sitePage?expand=canvasLayout";
var content = new Microsoft.Graph.BatchRequestContentCollection(graphClient);
var requestStepId = await content.AddBatchRequestStepAsync(graphPageRequest);
var batchResult = await graphClient.Batch.PostAsync(content);
var graphPage = await batchResult.GetResponseByIdAsync<SitePage>(requestStepId);

Note: I did not immediately find how to send the modified graphPageRequest and the batching approach is the first sample I found that worked. There might be an easier approach.

[andrueastman]

Depends on microsoftgraph/msgraph-metadata#401