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Net Core 6.0 compatibility? Getting OAuth2Exception: invalid_grant for ProcessCodeFlowAsync...
Trying to port a Windows .NET Standard to .NET Core 6.0 using Blazor Server. I've got the old application running just fine and I'm able to get the initial Authorization Code. Trying to pass that along with the key and secret, etc... and I get:
OAuth2Exception: invalid_grant
Dropbox.Api.DropboxOAuth2Helper.ProcessCodeFlowAsync(string code, string appKey, string appSecret, string redirectUri, HttpClient client, string codeVerifier)
docket2022.Pages.AuthDbxToken.ProcessDropboxCallback(string AuthCode) in AuthDbxToken.razor
I've made sure all the variables are passing by checking a console....
Uri uri = new Uri(NavManager.Uri);
Console.WriteLine("URI Absolute: " + uri.AbsoluteUri);
Console.WriteLine("AuthCode: " + AuthCode);
Console.WriteLine("ApiKeyString: " + ApiKeyString);
Console.WriteLine("ApiSecretString: " + ApiSecretString);
Console.WriteLine("Return URL: " + theState);
State.dbxToken = "Auth Code: " + AuthCode.ToString();
Console.WriteLine("-------------------------DropboxOAuth2Helper AuthDbxToken.razor--------------------");
OAuth2Response response = await DropboxOAuth2Helper.ProcessCodeFlowAsync(AuthCode, ApiKeyString, ApiSecretString, theState, null, null);
Of course I added a localhost redirect URI for my new project. What is strange is that scope, keys, secrets, etc.... is the same but the .NET Core version keeps getting this error. I've looked everywhere but I can't see up or down if there has been success or failure with .NET Core 6.0.
What does your GetAuthorizeUri call look like? Your GetAuthorizeUri configuration needs to match your ProcessCodeFlowAsync configuration. For example, if you passed a redirectUri to GetAuthorizeUri, you need to also pass that same redirectUri to ProcessCodeFlowAsync. See this sample code as an example.
You mentioned using a redirect URI, but if you're not passing it to ProcessCodeFlowAsync in this code, that could cause this error.
- Greg-DB
Dropbox Staff
What does your GetAuthorizeUri call look like? Your GetAuthorizeUri configuration needs to match your ProcessCodeFlowAsync configuration. For example, if you passed a redirectUri to GetAuthorizeUri, you need to also pass that same redirectUri to ProcessCodeFlowAsync. See this sample code as an example.
You mentioned using a redirect URI, but if you're not passing it to ProcessCodeFlowAsync in this code, that could cause this error.
That was it. Thank you! For reference if anyone is doing this in Blazor-Server (code thinned out to pertinent issue):
@page "/dbxAuth" @using System.Runtime.InteropServices @using System.Threading.Tasks @using Dropbox.Api @inject NavigationManager NavManager @code { public async Task ProcessDropboxCallback(string AuthCode) { // HERE IS WHERE I FIXED THE ISSUE var uriBuilder = new UriBuilder(NavManager.Uri); uriBuilder.Query = uri.Query.ToString(); uriBuilder.Fragment = null; uriBuilder.Query = null; OAuth2Response response = await DropboxOAuth2Helper.ProcessCodeFlowAsync(AuthCode, ApiKeyString, ApiSecretString, uriBuilder.Uri.AbsoluteUri, null, null); } }
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