Accessing MSGraph from Blazor WASM Running on ASWA

01-auth-login-aad.txt

https://<azure_static_webapp>.azurestaticapps.net/.auth/login/aad

02-auth-me.cs

var baseUri = "https://<azure_static_webapp>.azurestaticapps.net";
var http = new HttpClient() { BaseAddress = new Uri(baseUri) };
var response = await http.GetStringAsync("/.auth/me").ConfigureAwait(false);

03-auth-details.json

{
  "clientPrincipal": {
    "identityProvider":"aad",
    "userId":"<guid>",
    "userDetails":"<logged_in_email>",
    "userRoles":[
      "anonymous",
      "authenticated"
    ]
  }
}

04-client-principal.txt

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05-client-principal.cs

public class ClientPrincipal
{
    [JsonProperty("identityProvider")]
    public string IdentityProvider { get; set; }

    [JsonProperty("userId")]
    public string UserId { get; set; }

    [JsonProperty("userDetails")]
    public string UserDetails { get; set; }

    [JsonProperty("userRoles")]
    public IEnumerable<string> UserRoles { get; set; }
}

06-get-client-principal.cs

var bytes = Convert.FromBase64String((string)req.Headers["x-ms-client-principal"]);
var json = Encoding.UTF8.GetString(bytes);
var principal = JsonConvert.DeserializeObject<ClientPrincipal>(json);

var userEmail = principal.UserDetails;

07-local-settings.json

{
  "Values": {
    "LoginUri": "https://login.microsoftonline.com/",
    "TenantId": "<tenant_id>",
    "ClientId": "<client_id>",
    "ClientSecret": "<client_secret>",
    "ApiHost": "https://graph.microsoft.com/",
    "BaseUrl": "v1.0/"
  }
}

08-get-access-token.cs

private async Task<string> GetAccessTokenAsync()
{
    var apiHost = Environment.GetEnvironmentVariable("ApiHost");
    var scopes = new [] { $"{apiHost.TrimEnd('/')}/.default" };

    var options = new ConfidentialClientApplicationOptions()
    {
        Instance = Environment.GetEnvironmentVariable("LoginUri"),
        TenantId = Environment.GetEnvironmentVariable("TenantId"),
        ClientId = Environment.GetEnvironmentVariable("ClientId"),
        ClientSecret = Environment.GetEnvironmentVariable("ClientSecret"),
    };

    var authority = $"{options.Instance.TrimEnd('/')}/{options.TenantId}";

    var app = ConfidentialClientApplicationBuilder
                  .Create(options.ClientId)
                  .WithClientSecret(options.ClientSecret)
                  .WithAuthority(authority)
                  .Build();

    var result = await app.AcquireTokenForClient(scopes)
                          .ExecuteAsync()
                          .ConfigureAwait(false);

    var accessToken = result.AccessToken;
    return accessToken;
}

09-get-graph-client.cs

private async Task<GraphServiceClient> GetGraphClientAsync()
{
    var baseUri = $"{Environment.GetEnvironmentVariable("ApiHost").TrimEnd('/')}/{Environment.GetEnvironmentVariable("BaseUrl")}";
    var provider = new DelegateAuthenticationProvider(async p =>
                    {
                        var accessToken = await this.GetAccessTokenAsync().ConfigureAwait(false);
                        p.Headers.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
                    });
    var client = new GraphServiceClient(baseUri, provider);

    return await Task.FromResult(client).ConfigureAwait(false);
}

10-get-user.cs

var client = await this.GetGraphClientAsync().ConfigureAwait(false);

var users = await client.Users.Request().GetAsync().ConfigureAwait(false);
var user = users.SingleOrDefault(p => p.Mail == userEmail);
if (user == null)
{
    return new NotFoundResult();
}

11-user.json

{
  "accountEnabled": null,
  "ageGroup": null,
  "assignedLicenses": null,
  ...
  "displayName": "Justin Yoo",
  ...
  "givenName": "Justin",
  ...
  "mail": "justin.yoo@<external_tenant_name>.onmicrosoft.com",
  ...
  "surname": "Yoo",
  "usageLocation": null,
  "userPrincipalName": "justin.yoo_<external_tenant_name>.onmicrosoft.com#EXT#@<tenant_name>.onmicrosoft.com",
  ...
}

12-loggedin-user.cs

public class LoggedInUser
{
    public LoggedInUser(User user)
    {
        this.Upn = user?.UserPrincipalName;
        this.DisplayName = user?.DisplayName;
        this.Email = user?.Mail;
    }

    [JsonProperty("upn")]
    public virtual string Upn { get; set; }

    [JsonProperty("displayName")]
    public virtual string DisplayName { get; set; }

    [JsonProperty("email")]
    public virtual string Email { get; set; }
}

13-get-loggedin-user.cs

var loggedInUser = new LoggedInUser(user);

return new OkObjectResult(loggedInUser);

14-get-loggedin-user.cs

protected async Task<LoggedInUserDetails> GetLoggedInUserDetailsAsync()
{
    var details = default(LoggedInUserDetails);
    try
    {
        using (var response = await this._http.GetAsync("/api/users/get").ConfigureAwait(false))
        {
            response.EnsureSuccessStatusCode();

            var json = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
            details = JsonSerializer.Deserialize<LoggedInUserDetails>(json);
        }
    }
    catch
    {
    }

    return details;
}

15-get-loggedin-user-en.razor

<div class="page">
    ...
    <div class="main">
        ...
        <div class="top-row px-4 text-end">
            <span class="px-4">@DisplayName</span> | <a href="/logout">Logout</a>
        </div>
        ...
    </div>
</div>

@code {
    protected string DisplayName;

    protected override async Task OnInitializedAsync()
    {
        var loggedInUser = await GetLoggedInUserDetailsAsync().ConfigureAwait(false);
        DisplayName = loggedInUser?.DisplayName ?? "Not a registered user";
    }
}

15-get-loggedin-user-ko.razor

<div class="page">
    ...
    <div class="main">
        ...
        <div class="top-row px-4 text-end">
            <span class="px-4">@DisplayName</span> | <a href="/logout">로그아웃</a>
        </div>
        ...
    </div>
</div>

@code {
    protected string DisplayName;

    protected override async Task OnInitializedAsync()
    {
        var loggedInUser = await GetLoggedInUserDetailsAsync().ConfigureAwait(false);
        DisplayName = loggedInUser?.DisplayName ?? "등록된 사용자 아님";
    }
}