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PayPalAPIInterfaceServiceService and SetExpressCheckout config / credential information

I created an app in my business account on this page:
https://developer.paypal.com/developer/applications/
When I click on the app I created I see the following:
Sandbox account, Client ID, and Secret.
I am trying to call SetExpressCheckout… but the documentation is unclear and examples are all over the map.
Basically I’m seeing things like:
var request = new SetExpressCheckoutReq() { … };
var config = new Dictionary<string, string>()
{
{ "mode", "sandbox" }, // some variations of these values
{ "clientId", "fromAbovePage" },
{ "clientSecret", "fromAbovePage" },
{ "sandboxAccount", "fromAbovePage" },
{ "apiUsername", "IDontKnow" },
{ "apiPassword", "IDontKnow" },
{ "apiSignature", "IDontKnow" }
};
var service = new PayPalAPIInterfaceServiceService(config);
var response = service.SetExpressCheckout(request, new SignatureCredential(config["apiUsername"], config["apiPassword"], config["apiSignature"]));
Also, kind of weird that credentials go into both the PayPalAPIInterfaceServiceService and the actual SetExpressCheckout call.
What are (and where do I get) the correct values for the above config? (the request itself I have pretty much figured out)
Note: PayPal support told me that I need to use Reference Transactons in order to charge varying amounts over potentially varying times without subsequent user interaction, if that is relevant.
I would love to see examples of this with the most recent API's if anyone has that information as well.
Thank you.

SetExpressCheckout is a legacy NVP API
For sandbox, it uses credentials from the "Profile" of a sandbox account in https://www.paypal.com/signin?intent=developer&returnUri=https%3A%2F%2Fdeveloper.paypal.com%2Fdeveloper%2Faccounts%2F
For live, https://www.paypal.com/api
ClientID/Secret credentials are used for the current v2/checkout/orders REST API, which at the moment does not have any public documentation for vaulting or reference transactions; it is for one time payments. You can find information for a server-side integration at https://developer.paypal.com/docs/checkout/reference/server-integration/
If you are using this REST API integration, create two routes --one for 'Set Up Transaction' and one for 'Create Transaction'. Then pair them with this approval flow: https://developer.paypal.com/demo/checkout/#/pattern/server

Error Calling Calendar API: Principal must be an email address

We wrote a software more than 1 year ago to sync events from google calendars. It's been working since March 2018, but it suddendly stop working this months on every Gsuite instances we use for us and for our customers.
The problem is that we are using a service account to access calendar resources events via google CalendarAPI v3.
After authenticating with service account credentials , for every service call we now encounter the error:
"Error:\"invalid_request\", Description:\"Principal must be an email address\", Uri:\"\""
I cannot find an answer anywhere about this problem, it sounds like a policy change on Google service, but I cannot be sure about this.
It seems like Google API is complaining about service account email, that isn't actually a real valid email. It is in this format:
mydomain.com_(client_id)313.......#resource.calendar.google.com
Do you think the problem could be related to the service account email address?
And why it was working before April and now stop working?
One possible solution, not yet tried:
I sow it is possible to use "delegation" for the service acount.
What would happens if I try to use a valid user email and delegate it upon my service account?
/* function I use to authenticate my service account to Google Calendar
* service. serviceAccount is the email (Principal not working?) and json is
* the key generated for him.
*/
public void bindCalendarService(string json, string serviceAccount)
{
var cr = Newtonsoft.Json.JsonConvert.DeserializeObject<PersonalServiceAccountCred>(json);
ServiceAccountCredential xCred = new ServiceAccountCredential(new ServiceAccountCredential.Initializer(cr.client_id, cr.token_uri)
{
Scopes = new string[] {
CalendarService.Scope.Calendar,
},
User = serviceAccount
}.FromPrivateKey(cr.private_key));
CalendarService calendarService = new CalendarService(new BaseClientService.Initializer()
{
HttpClientInitializer = xCred
});
this.calendarService = calendarService;
}

you need to give access to unsecured apps on google account security,
try this : https://support.google.com/accounts/answer/6010255?hl=en
if it do not work talk to me.

I solve today the problem in onother way.
1) I tried to implement delegation like it is wxplained on:
https://developers.google.com/identity/protocols/OAuth2ServiceAccount#delegatingauthority
It works.
2) Without delegation, I changed my metod posted avove in this way:
var credentialParameters = NewtonsoftJsonSerializer.Instance.Deserialize(json);
ServiceAccountCredential xCred = new ServiceAccountCredential(
new ServiceAccountCredential.Initializer(**credentialParameters.ClientEmail**)
{
Scopes = new string[] {
CalendarService.Scope.Calendar
},
User = serviceAccount, // service account's email
}.FromPrivateKey(credentialParameters.PrivateKey));
It works even in this way.
It is still a mistery why above code stopped working after 1 year.
Hope it will help someone
Thanks

MSAL Error message AADSTS65005 when trying to get token for accessing custom api

I downloaded the example below to get an access token from MS Graph and it worked fine. Now I changed the code to get a token from a custom web API. On apps.dev.microsoft.com I registered a client application and an the API.
Client and server registration in AD
private static async Task<AuthenticationResult> GetToken()
{
const string clientId = "185adc28-7e72-4f07-a052-651755513825";
var clientApp = new PublicClientApplication(clientId);
AuthenticationResult result = null;
string[] scopes = new string[] { "api://f69953b0-2d7f-4523-a8df-01f216b55200/Test" };
try
{
result = await clientApp.AcquireTokenAsync(scopes, "", UIBehavior.SelectAccount, string.Empty);
}
catch (Exception x)
{
if (x.Message == "User canceled authentication")
{
}
return null;
}
return result;
}
When I run the code I login to AD via the dialog en get the following exception in the debugger:
Error: Invalid client Message = "AADSTS65005: The application
'CoreWebAPIAzureADClient' asked for scope 'offline_access' that
doesn't exist on the resource. Contact the app vendor.\r\nTrace ID:
56a4b5ad-8ca1-4c41-b961-c74d84911300\r\nCorrelation ID:
a4350378-b802-4364-8464-c6fdf105cbf1\r...
Error message
Help appreciated trying for days...

For anyone still striking this problem, please read this:
https://www.andrew-best.com/posts/please-sir-can-i-have-some-auth/
You'll feel better after this guy reflects all of your frustrations, except that he works it out...
If using adal.js, for your scope you need to use
const tokenRequest = {
scopes: ["https://management.azure.com/user_impersonation"]
};
I spent a week using
const tokenRequest = {
scopes: ["user_impersonation"]
};
.. since that is the format that the graph API scopes took

As of today, the V2 Endpoint does not support API access other than the Microsoft Graph. See the limitations of the V2 app model here.
Standalone Web APIs
You can use the v2.0 endpoint to build a Web API that is secured with
OAuth 2.0. However, that Web API can receive tokens only from an
application that has the same Application ID. You cannot access a Web
API from a client that has a different Application ID. The client
won't be able to request or obtain permissions to your Web API.
For the specific scenario that you are trying to accomplish, you need to use the V1 App Model (register apps on https://portal.azure.com).
In the very near future, V2 apps will be enabled to call other APIs other than Microsoft Graph, so your scenario will be supported, but that is just not the case today. You should keep an eye out on our documentation for this update.

In your (server) application registration in AAD, you need to specify your scopes in the oauth2Permissions element.
You may already have a user_impersonation scope set. Copy that as a baseline, give it a unique GUID and value, and then AAD will let your client request an access token with your new scope.

Google Data API Authorization Redirect URI Mismatch

Background
I am wanting to write a small, personal web app in .NET Core 1.1 to interact with YouTube and make some things easier for me to do and I am following the tutorials/samples in Google's YouTube documentation. Sounds simple enough, right? ;)
Authenticating with Google's APIs seems impossible! I have done the following:
Created an account in the Google Developer Console
Created a new project in the Google Developer Console
Created a Web Application OAuth Client ID and added my Web App debug URI to the list of approved redirect URIs
Saved the json file provided after generating the OAuth Client ID to my system
In my application, my debug server url is set (and when my application launches in debug, it's using the url I set which is http://127.0.0.1:60077).
However, when I attempt to authenticate with Google's APIs, I recieve the following error:
That’s an error.
Error: redirect_uri_mismatch
The redirect URI in the request, http://127.0.0.1:63354/authorize/,
does not match the ones authorized for the OAuth client.
Problem
So now, for the problem. The only thing I can find when searching for a solution for this is people that say
just put the redirect URI in your approved redirect URIs
Unfortunately, the issue is that every single time my code attempts to authenticate with Google's APIs, the redirect URI it is using changes (the port changes even though I set a static port in the project's properties). I cannot seem to find a way to get it to use a static port. Any help or information would be awesome!
NOTE: Please don't say things like "why don't you just do it this other way that doesn't answer your question at all".
The code
client_id.json
{
"web": {
"client_id": "[MY_CLIENT_ID]",
"project_id": "[MY_PROJECT_ID]",
"auth_uri": "https://accounts.google.com/o/oauth2/auth",
"token_uri": "https://accounts.google.com/o/oauth2/token",
"auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
"client_secret": "[MY_CLIENT_SECRET]",
"redirect_uris": [
"http://127.0.0.1:60077/authorize/"
]
}
}
Method That Is Attempting to Use API
public async Task<IActionResult> Test()
{
string ClientIdPath = #"C:\Path\To\My\client_id.json";
UserCredential credential;
using (var stream = new FileStream(ClientIdPath, FileMode.Open, FileAccess.Read))
{
credential = await GoogleWebAuthorizationBroker.AuthorizeAsync(
GoogleClientSecrets.Load(stream).Secrets,
new[] { YouTubeService.Scope.YoutubeReadonly },
"user",
CancellationToken.None,
new FileDataStore(this.GetType().ToString())
);
}
var youtubeService = new YouTubeService(new BaseClientService.Initializer()
{
HttpClientInitializer = credential,
ApplicationName = this.GetType().ToString()
});
var channelsListRequest = youtubeService.Channels.List("contentDetails");
channelsListRequest.Mine = true;
// Retrieve the contentDetails part of the channel resource for the authenticated user's channel.
var channelsListResponse = await channelsListRequest.ExecuteAsync();
return Ok(channelsListResponse);
}
Project Properties

The Original Answer works, but it is NOT the best way to do this for an ASP.NET Web Application. See the update below for a better way to handle the flow for an ASP.NET Web Application.
Original Answer
So, I figured this out. The issue is that Google thinks of a web app as a JavaScript based web application and NOT a web app with server side processing. Thus, you CANNOT create a Web Application OAuth Client ID in the Google Developer Console for a server based web application.
The solution is to select the type Other when creating an OAuth Client ID in the Google Developer Console. This will have Google treat it as an installed application and NOT a JavaScript application, thus not requiring a redirect URI to handle the callback.
It's somewhat confusing as Google's documentation for .NET tells you to create a Web App OAuth Client ID.
Feb 16, 2018 Updated Better Answer:
I wanted to provide an update to this answer. Though, what I said above works, this is NOT the best way to implement the OAuth workflow for a ASP.NET solution. There is a better way which actually uses a proper OAuth 2.0 flow. Google's documentation is terrible in regards to this (especially for .NET), so I'll provide a simple implementation example here. The sample is using ASP.NET core, but it's easily adapted to the full .NET framework :)
Note: Google does have a Google.Apis.Auth.MVC package to help simplifiy this OAuth 2.0 flow, but unfortunately it's coupled to a specific MVC implementation and does not work for ASP.NET Core or Web API. So, I wouldn't use it. The example I'll be giving will work for ALL ASP.NET applications. This same code flow can be used for any of the Google APIs you've enabled as it's dependent on the scopes you are requesting.
Also, I am assuming you have your application set up in your Google Developer dashboard. That is to say that you have created an application, enabled the necessary YouTube APIs, created a Web Application Client, and set your allowed redirect urls properly.
The flow will work like this:
The user clicks a button (e.g. Add YouTube)
The View calls a method on the Controller to obtain an Authorization URL
On the controller method, we ask Google to give us an Authorization URL based on our client credentials (the ones created in the Google Developer Dashboard) and provide Google with a Redirect URL for our application (this Redirect URL must be in your list of accepted Redirect URLs for your Google Application)
Google gives us back an Authorization URL
We redirect the user to that Authorization URL
User grants our application access
Google gives our application back a special access code using the Redirect URL we provided Google on the request
We use that access code to get the Oauth tokens for the user
We save the Oauth tokens for the user
You need the following NuGet Packages
Google.Apis
Google.Apis.Auth
Google.Apis.Core
Google.apis.YouTube.v3
The Model
public class ExampleModel
{
public bool UserHasYoutubeToken { get; set; }
}
The Controller
public class ExampleController : Controller
{
// I'm assuming you have some sort of service that can read users from and update users to your database
private IUserService userService;
public ExampleController(IUserService userService)
{
this.userService = userService;
}
public async Task<IActionResult> Index()
{
var userId = // Get your user's ID however you get it
// I'm assuming you have some way of knowing if a user has an access token for YouTube or not
var userHasToken = this.userService.UserHasYoutubeToken(userId);
var model = new ExampleModel { UserHasYoutubeToken = userHasToken }
return View(model);
}
// This is a method we'll use to obtain the authorization code flow
private AuthorizationCodeFlow GetGoogleAuthorizationCodeFlow(params string[] scopes)
{
var clientIdPath = #"C:\Path\To\My\client_id.json";
using (var fileStream = new FileStream(clientIdPath, FileMode.Open, FileAccess.Read))
{
var clientSecrets = GoogleClientSecrets.Load(stream).Secrets;
var initializer = new GoogleAuthorizationCodeFlow.Initializer { ClientSecrets = clientSecrets, Scopes = scopes };
var googleAuthorizationCodeFlow = new GoogleAuthorizationCodeFlow(initializer);
return googleAuthorizationCodeFlow;
}
}
// This is a route that your View will call (we'll call it using JQuery)
[HttpPost]
public async Task<string> GetAuthorizationUrl()
{
// First, we need to build a redirect url that Google will use to redirect back to the application after the user grants access
var protocol = Request.IsHttps ? "https" : "http";
var redirectUrl = $"{protocol}://{Request.Host}/{Url.Action(nameof(this.GetYoutubeAuthenticationToken)).TrimStart('/')}";
// Next, let's define the scopes we'll be accessing. We are requesting YouTubeForceSsl so we can manage a user's YouTube account.
var scopes = new[] { YouTubeService.Scope.YoutubeForceSsl };
// Now, let's grab the AuthorizationCodeFlow that will generate a unique authorization URL to redirect our user to
var googleAuthorizationCodeFlow = this.GetGoogleAuthorizationCodeFlow(scopes);
var codeRequestUrl = googleAuthorizationCodeFlow.CreateAuthorizationCodeRequest(redirectUrl);
codeRequestUrl.ResponseType = "code";
// Build the url
var authorizationUrl = codeRequestUrl.Build();
// Give it back to our caller for the redirect
return authorizationUrl;
}
public async Task<IActionResult> GetYoutubeAuthenticationToken([FromQuery] string code)
{
if(string.IsNullOrEmpty(code))
{
/*
This means the user canceled and did not grant us access. In this case, there will be a query parameter
on the request URL called 'error' that will have the error message. You can handle this case however.
Here, we'll just not do anything, but you should write code to handle this case however your application
needs to.
*/
}
// The userId is the ID of the user as it relates to YOUR application (NOT their Youtube Id).
// This is the User ID that you assigned them whenever they signed up or however you uniquely identify people using your application
var userId = // Get your user's ID however you do (whether it's on a claim or you have it stored in session or somewhere else)
// We need to build the same redirect url again. Google uses this for validaiton I think...? Not sure what it's used for
// at this stage, I just know we need it :)
var protocol = Request.IsHttps ? "https" : "http";
var redirectUrl = $"{protocol}://{Request.Host}/{Url.Action(nameof(this.GetYoutubeAuthenticationToken)).TrimStart('/')}";
// Now, let's ask Youtube for our OAuth token that will let us do awesome things for the user
var scopes = new[] { YouTubeService.Scope.YoutubeForceSsl };
var googleAuthorizationCodeFlow = this.GetYoutubeAuthorizationCodeFlow(scopes);
var token = await googleAuthorizationCodeFlow.ExchangeCodeForTokenAsync(userId, code, redirectUrl, CancellationToken.None);
// Now, you need to store this token in rlation to your user. So, however you save your user data, just make sure you
// save the token for your user. This is the token you'll use to build up the UserCredentials needed to act on behalf
// of the user.
var tokenJson = JsonConvert.SerializeObject(token);
await this.userService.SaveUserToken(userId, tokenJson);
// Now that we've got access to the user's YouTube account, let's get back
// to our application :)
return RedirectToAction(nameof(this.Index));
}
}
The View
#using YourApplication.Controllers
#model YourApplication.Models.ExampleModel
<div>
#if(Model.UserHasYoutubeToken)
{
<p>YAY! We have access to your YouTube account!</p>
}
else
{
<button id="addYoutube">Add YouTube</button>
}
</div>
<script>
$(document).ready(function () {
var addYoutubeUrl = '#Url.Action(nameof(ExampleController.GetAuthorizationUrl))';
// When the user clicks the 'Add YouTube' button, we'll call the server
// to get the Authorization URL Google built for us, then redirect the
// user to it.
$('#addYoutube').click(function () {
$.post(addYoutubeUrl, function (result) {
if (result) {
window.location.href = result;
}
});
});
});
</script>

As referred here, you need to specify a fix port for the ASP.NET development server like How to fix a port number in asp.NET development server and add this url with the fix port to the allowed urls. Also as stated in this thread, when your browser redirects the user to Google's oAuth page, you should be passing as a parameter the redirect URI you want Google's server to return to with the token response.

I noticed that there is easy non-programmatic way around.
If you have typical monotlith application built in typical MS convention(so not compatible with 12factor and typical DDD) there is an option to tell your Proxy WWW server to rewrite all requests from HTTP to HTTPS so even if you have set up Web App on http://localhost:5000 and then added in Google API url like: http://your.domain.net/sigin-google, it will work perfectly and it is not that bas because it is much safer to set up main WWW to rewrite all to HTTPS.
It is not very good practice I guess however it makes sense and does the job.

I've struggled with this issue for hours in a .net Core application. What finally fixed it for me was, in the Google developers console, to create and use a credential for "Desktop app" instead of a "Web application".

Yeah!! Using credentials of desktop app instead of web app worked for me fine. It took me more than 2 days to figure out this problem. The main problem is that google auth library dose not adding or supporting http://localhost:8000 as redirect uri for web app creds but credentials of desktop app fixed that issue. Cause its supporting http://___ connection instead of https: connection for redirect uri

Google Apis v3 in ASP.Net - "Unauthorized client or scope in request"

Maybe I am simply not getting "it", with "it" being the overall setup needed to make this work.
I have a website that scrapes other sites for sporting events. I want to automatically create Google Calendar events from the results, so I want to give my Web Application Read/Write access on a Calendar in my GMail account.
I have been trying to wrap my head around this for a week now, but I can't get it to work and it is crushing my self-esteem as a developer.
The way I "understand" it is that I need a Google API v3 Service Account, because I don't need an API key for a particular user. Or do I need a Simple API key (instead of oAuth)?
Anyways, I went with the Service Account.
In my HomeController I am trying to GET a Calendar so I know it all works.
public void Calendar()
{
string serviceAccountEmail = "...#developer.gserviceaccount.com";
var certificate = new X509Certificate2(
Server.MapPath("~") + #"\App_Data\key.p12",
"notasecret",
X509KeyStorageFlags.Exportable);
ServiceAccountCredential credential =
new ServiceAccountCredential(
new ServiceAccountCredential.Initializer(serviceAccountEmail)
{
Scopes = new[]
{
CalendarService.Scope.Calendar
},
User = "MY-GMAIL-EMAIL" // Is this correct?
}
.FromCertificate(certificate));
BaseClientService.Initializer initializer = new BaseClientService.Initializer();
initializer.HttpClientInitializer = credential;
initializer.ApplicationName = "CALENDAR NAME"; // Correct?
var service = new CalendarService(initializer);
var list = service.CalendarList.List().Execute().Items; // Exception :-(
}
The error I am getting:
An exception of type 'Google.Apis.Auth.OAuth2.Responses.TokenResponseException' occurred in Google.Apis.dll but was not handled in user code
Additional information: Error:"unauthorized_client", Description:"Unauthorized client or scope in request.", Uri:""
So I tried a bunch of things in Google Calendar, like making it public, adding the service account email as a READ/WRITE user.
What do I need to do to authorize my Web Application so it can create events on my behalf?

I have done this with the service account in a similar post. I changed a bit of my code and got it working to list my calendars by switching a few things around. I can create events as well. I didn't add a user as you have done in the initializer, and under application name, it is the name of the application in the dev console. Make sure you name your application. Make sure your service account is shared with your account.
I slightly changed the list part of your code to this in mine and got back the my list of calendars.
var list = service.CalendarList.List();
var listex = list.Execute();
Check out my example at Google API Calender v3 Event Insert via Service Account using Asp.Net MVC