Functions.Extensions.StaticWebApps

Azure Functions extension that extracts user information for use in a Static Web Apps api.

Install

This extension is available as a NuGet package.

dotnet install SpringComp.Functions.Extensions.StaticWebApps

Usage

This extension is designed to work well with azure functions used as backend apis for Azure Static Web Apps. It implements the standard code to retrieve the authenticated user details as a ClaimsPrincipal object.

In your HTTP triggered api function add a parameter typed ClaimsPrincipal decorated using the UserInfo attribute.

    [FunctionName("HttpTrigger")]
    public async Task<HttpResponseMessage> Run(
        [HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "message")] HttpRequest req,
        [UserInfo] ClaimsPrincipal identity,
        ILogger log)
    {
      log.LogInformation("C# HTTP trigger function processed a request.");

      var dictionary = new Dictionary<string, object>();

      foreach (var claim in identity.Claims)
      {
        log.LogTrace($"{claim.Type}: {claim.Value}");
        if (dictionary.ContainsKey(claim.Type))
        {
          var items = dictionary[claim.Type] as List<string>;
          if (items == null)
            items = new List<string>(new[] { dictionary[claim.Type] as string });
          items.Add(claim.Value);
          dictionary[claim.Type] = items;
        }
        else
        {
          dictionary.Add(claim.Type, claim.Value);
        }
      }

      string output;
      using (var stream = new MemoryStream())
      {
        await System.Text.Json.JsonSerializer.SerializeAsync(stream, dictionary);
        output = Encoding.UTF8.GetString(stream.ToArray());
        log.LogTrace(output);
      }

      var response = new HttpResponseMessage();
      response.Content = new StringContent(output, Encoding.UTF8, "application/json");
      return response;
    }