Accessing parsed Applications from ApplicationCollectionResponse in MS Graph SDK

I want to extract the app registration and service principal for my application knowing only the appId. This requires me to append (appId='appId') to the URIs.

https://graph.microsoft.com/v1.0/applications(appId='appId')
https://graph.microsoft.com/v1.0/servicePrincipals(appId='appId')

Since you cannot append to the URI, I had to resort to using RequestInformation, and then using RequestAdapter.SendAsync to fetch the info. Here's the full code

var requestInfo = graphServiceClient.Applications.ToGetRequestInformation();
var fixedUri = $"{requestInfo.URI}(appId='<my app id here>')";
requestInfo.URI = new Uri(fixedUri);
var apps = await graphServiceClient.RequestAdapter.SendAsync(requestInfo, ApplicationCollectionResponse.CreateFromDiscriminatorValue).ConfigureAwait(false);

That works fine. But the result variable has an empty Value property, so I'm not getting any parsed Application back. I do however see the application as data dictionary in apps.AdditionalData so I know the data gets returned. What do I need to do to get the Value populated?

Note that I already found graphServiceClient.ApplicationsWithAppId and graphServiceClient.ServicePrincipalWithAppId, so I do have a solution, but I'm still curious about the manual way

The reason is that https://graph.microsoft.com/v1.0/applications(appId='appId') doesn't return a collection but a single entity, so you need to use Application.CreateFromDiscriminatorValue instead of ApplicationCollectionResponse.CreateFromDiscriminatorValue.

The result will be an instance of the Application.

var requestInfo = graphServiceClient.Applications.ToGetRequestInformation();
var fixedUri = $"{requestInfo.URI}(appId='<my app id here>')";
requestInfo.URI = new Uri(fixedUri);
var app = await graphServiceClient.RequestAdapter.SendAsync(requestInfo, Application.CreateFromDiscriminatorValue).ConfigureAwait(false);

> I agree with @user2250152, make use of
> Application.CreateFromDiscriminatorValue to fetch the Application details.

I used the below code to fetch the application details:

using Microsoft.Graph.Models;
using Microsoft.Graph;
using Azure.Identity;
using Microsoft.Graph.Models.ODataErrors;
using Microsoft.Kiota.Abstractions;


var scopes = new[] { "https://graph.microsoft.com/.default" };

var clientId = "ClientID";
var tenantId = "TenantID";
var clientSecret = "ClientSecret";

var options = new ClientSecretCredentialOptions
{
    AuthorityHost = AzureAuthorityHosts.AzurePublicCloud,
};

var clientSecretCredential = new ClientSecretCredential(
    tenantId, clientId, clientSecret, options);

GraphServiceClient graphClient = new GraphServiceClient(clientSecretCredential, scopes);

var requestInfo = graphClient.Applications.ToGetRequestInformation();
var fixedUri = $"{requestInfo.URI}(Id='ID')";
requestInfo.URI = new Uri(fixedUri);
var app = await graphClient.RequestAdapter.SendAsync(requestInfo, Application.CreateFromDiscriminatorValue).ConfigureAwait(false);

Console.WriteLine(app.DisplayName);
Console.WriteLine(app.Id);

To fetch the Service Principal details, modify the code like below:

var requestInfo = graphClient.ServicePrincipals.ToGetRequestInformation();
var fixedUri = $"{requestInfo.URI}(Id='SPID')";
requestInfo.URI = new Uri(fixedUri);
var app = await graphClient.RequestAdapter.SendAsync(requestInfo, ServicePrincipal.CreateFromDiscriminatorValue).ConfigureAwait(false);