Accessing MS Project Server with ProjectContext and ADFS

If you need to access Microsoft Project Server, you can use the ProjectContext class from the Microsoft.ProjectServer.Client.dll assembly. This class inherits from the SharePoint ClientContext:
[code language=”csharp”]
using System;
using Microsoft.SharePoint.Client;

namespace Microsoft.ProjectServer.Client
{
public class ProjectContext : ClientContext
{…
[/code]
and adds a few new methods and properties.

If your SharePoint is running with ADFS, you can use the GetADFSUserNameMixedAuthenticatedContext-methode to authenticate with the ClientContext. The message needs some additional information like sts (hostname of ADFS), idpId (identifier of the ADFS relying party) … and returns an authenticated ClientContext.
[code language=”csharp”]
OfficeDevPnP.Core.AuthenticationManager am = new OfficeDevPnP.Core.AuthenticationManager();
ClientContext ctx = am.GetADFSUserNameMixedAuthenticatedContext(
siteUrl: “https://myprojects.mycompany.com”,
user: USERNAME,
password: PASSWORD,
domain: “DOMAIN”,
sts: “HOSTNAME OF ADFS”,
idpId: “sharepoint:myprojects:mycompany”);
[/code]

But the ProjectContext can only be created via the ProjectContext-constructor, the GetADFSUserNameMixedAuthenticatedContext cannot return a ProjectContext and the ClientContext cannot be casted to the ProjectContext. So how to authenticate against ADFS?
The solution is to use GetFedAuthCookie-method from the UsernameMixed()-class. It must be executed in the ExecutingWebRequest-event and applied the federation cookie to the cookie container of the web request:
[code language=”csharp”]
string projectUrl = “https://myprojects.mycompany.com”;
ProjectContext pc = new ProjectContext(projectUrl);
pc.ExecutingWebRequest += delegate (object oSender, WebRequestEventArgs webRequestEventArgs)
{
CookieContainer fedAuth = new OfficeDevPnP.Core.IdentityModel.TokenProviders.ADFS.UsernameMixed().GetFedAuthCookie(
projectUrl,
string.Format(“{0}\\{1}”, “DOMAIN”, USERNAME),
PASSWORD,
new Uri(string.Format(“https://{0}/adfs/services/trust/13/usernamemixed”, “HOSTNAME OF ADFS”)),
“sharepoint:myprojects:mycompany”,
10);
webRequestEventArgs.WebRequestExecutor.WebRequest.CookieContainer = fedAuth;
};
var projects = pc.Projects;
pc.Load(projects);
pc.ExecuteQuery();
[/code]