[DRAFT] SharePoint Graph API support

[Drakonian]

Summary

This is the first version of the SharePoint Graph API module that leverages the Microsoft Graph module.

After analyzing the current REST implementation, I concluded that it cannot be changed without breaking backward compatibility. In addition, the REST and Graph APIs have completely different data models and sets of fields, which makes it impossible to reuse the same tables for entities that REST uses.

Therefore, adding a separate SharePoint Graph Client seemed the simplest and most natural solution. I also considered factory/builder patterns and dependency injection, but for the reasons mentioned above these approaches did not seem optimal, they don’t fit well and would greatly complicate the overall use of the SharePoint module.

I have already tested this code locally in various scenarios, and it behaves well. My plans are:

• Detail review of all the code with improvements where necessary
• Gathering feedback from the community and Microsoft
• Test pagination
• Test large file uploads
• Restructuring the folders so that REST and Graph reside in separate, peer-level folders
• Writing tests

Examples of how to use:

local procedure GetDrivesFromSite()
var
    TempGraphDrive: Record "SharePoint Graph Drive" temporary;
    SharePointGraphClient: Codeunit "SharePoint Graph Client";
    GraphAuthorization: Codeunit "Graph Authorization";
    GraphAuthInterface: Interface "Graph Authorization";
begin
    GraphAuthInterface := GraphAuthorization.CreateAuthorizationWithClientCredentials(
        TenantIdValue,
        ClientIdValue,
        ClientSecretValue,
        GraphScopeLbl);

    SharePointGraphClient.Initialize(SharePointUrlValue, GraphAuthInterface);

    if not SharePointGraphClient.GetDrives(TempGraphDrive) then
        Message('No drives found.');

    if TempGraphDrive.FindSet() then
        repeat
            Message('Drive Name: %1\Type: %2\Owner: %3\Quota Used: %4 of %5\Created: %6',
                TempGraphDrive.Name,
                TempGraphDrive.DriveType,
                TempGraphDrive.OwnerName,
                TempGraphDrive.QuotaUsed,
                TempGraphDrive.QuotaTotal,
                TempGraphDrive.CreatedDateTime);
        until TempGraphDrive.Next() = 0;
end;

local procedure UploadFileToRootDriveFolder()
var
    TempGraphDriveItem: Record "SharePoint Graph Drive Item" temporary;
    SharePointGraphClient: Codeunit "SharePoint Graph Client";
    GraphAuthorization: Codeunit "Graph Authorization";
    GraphAuthInterface: Interface "Graph Authorization";
    Diagnostics: Interface "HTTP Diagnostics";
    FileInStream: InStream;
    FileName: Text;
    FolderPath: Text;
begin
    GraphAuthInterface := GraphAuthorization.CreateAuthorizationWithClientCredentials(
        TenantIdValue,
        ClientIdValue,
        ClientSecretValue,
        GraphScopeLbl);

    SharePointGraphClient.Initialize(SharePointUrlValue, GraphAuthInterface);

    FolderPath := 'TestFolder'; //To root drive folder as we not specified DriveId
    if not UploadIntoStream('Select a file to upload', '', '', FileName, FileInStream) then
        exit;

    if SharePointGraphClient.UploadFile(FolderPath, FileName, FileInStream, TempGraphDriveItem) then
        Message('File uploaded successfully: %1', TempGraphDriveItem.Name)
    else begin
        Diagnostics := SharePointGraphClient.GetDiagnostics();
        Error('Error: %1 - %2', Diagnostics.GetHttpStatusCode(), Diagnostics.GetResponseReasonPhrase());
    end;
end;

Work Item(s)

Fixes #3198

Fixes AB#568746

[Drakonian]

@pri-kise

[JesperSchulz]

Very interesting contribution! Please allow me to take a much closer look at your code in the coming days. Unfortunately I will be on the road next week, so this might take me a short while to get to - but I'll be on it soon!

[Drakonian]

Very interesting contribution! Please allow me to take a much closer look at your code in the coming days. Unfortunately I will be on the road next week, so this might take me a short while to get to - but I'll be on it soon!

Thank you, I’ll look forward to your feedback -)

[pri-kise]

First of all: I really appreciate the work you have done for this PR.

I'm unsure if maybe some of the functionalities in the graph helper codeunits should maybe better be placed into the graph client module.
I only took a short look into the new code so far. I will need some more time to look into the changes in more detail.

Update:
I'm not sure if it's really helpful to provide a boolean value as return value on all those functions.
How should anyone know why the got false.

I think that it would be more helpful to return errors when something didn't went well.

Furthermore on your planned improvements for pagination:
I'm not sure if this is possible with the GraphOptionalParameters, but I think that it would be helpful if we could specify a range from outside, too.
What I mean is that sometimes we might want to control the pagination steps from outside.

[Drakonian]

@pri-kise

Thank you for such a helpful review of the PR. Your remarks are very useful.

1. I added an HTTP client handler, of course, it is absolutely essential here.
2. I completely agree with your point about the boolean, it's a relic from an older code version where I was experimenting with building a SharePoint Graph module (trying to merge with the SharePoint REST module). I prefer the approach used in the Azure Blob Storage API, where a method returns an object containing detailed information about the operation, so I’ve applied a similar pattern here.

Regarding managing pagination externally, that’s an excellent observation, but I’m still considering the best way to implement it. I’ll think through an approach that is convenient.

I believe pagination would be best handled at the Microsoft Graph module level, this needs some further thought.

My plans: at the moment I intend to keep improving the code and finish writing the tests.