Dear Community Experts,
I have created a .NET Core 6 web application for my husband's stamp collecting hobby [SNIP] and I would like to display some of his stamp images in the application from his Dropbox folder "Gourmet Philatelist". I went through all the samples in the .NET SDK for Dropbox in my Dropbox Api Test application, but I cannot get it to work in the stamp collecting web application. Here are the results of my attempts:
1. Using PKCEOAuthFlow();
var OAuthFlow = new PKCEOAuthFlow();
var redirect = OAuthFlow.GetAuthorizeUri(OAuthResponseType.Code,
AppKey,
RedirectUri.ToString(),
state: state,
tokenAccessType: TokenAccessType.Offline,
scopeList: scopeList,
includeGrantedScopes: IncludeGrantedScopes.None);
AcquireAccessToken: blows up trying to process the authorizeUri. I have tried registering many, many, different redirect urls using localhost with different ports like (https://localhost:7184/authorize and https://localhost:7184/gallery/auth) in the App center, but I cannot get it to work. (There is a file in the web application "index.html" like in the PKCEOAuthFlow sample). I also have the handler methods in the code.
// var state = Guid.NewGuid().ToString("N");
// var OAuthFlow = new PKCEOAuthFlow();
// var authorizeUri = OAuthFlow.GetAuthorizeUri(OAuthResponseType.Code, AppKey, null, state: state, tokenAccessType: TokenAccessType.Offline, scopeList: scopeList, includeGrantedScopes: includeGrantedScopes);
// var http = new HttpListener();
// http.Prefixes.Add(LoopbackHost);
// http.Start();
// System.Diagnostics.Process.Start(authorizeUri.ToString()); BLOWS UP HERE
// // Handle OAuth redirect and send URL fragment to local server using JS.
// await HandleOAuth2Redirect(http);
// // Handle redirect from JS and process OAuth response.
// var redirectUri = await HandleJSRedirect(http);
// Console.WriteLine("Exchanging code for token");
// var tokenResult = await OAuthFlow.ProcessCodeFlowAsync(redirectUri, AppKey, RedirectUri.ToString(), state);
// Console.WriteLine("Finished Exchanging Code for Token");
2.) Using PKCEOAuthFlow() with /Gallery/Auth redirect Url instead of url fragment in the index.html file.
I do get the AccessToken and the RefreshToken, but when I call dbx.Sharing.CreateSharedLinkWithSettingsAsync using the RefreshToken I get an error saying it is an invalid token.
3.) Tried again using DropboxOAuth2Helper - BLOWS UP HERE: SaveGalleryItem() - await dbx.Sharing.CreateSharedLinkWithSettingsAsync
ERROR: Invalid Grant
private string RedirectUri
{
get
{
var host = _httpContextAccessor.HttpContext.Request.Host;
var port = _httpContextAccessor.HttpContext.Request.Host.Port;
if (host.Host.ToLower(CultureInfo.InvariantCulture) == "localhost")
{
return "https://localhost:7184/Gallery/Auth";
}
var builder = new UriBuilder(
Uri.UriSchemeHttps,
host.Host);
builder.Path = "/Gallery/Auth";
return builder.ToString();
}
}
var state = Guid.NewGuid().ToString("N");
string[] scopeList = new string[4] { "files.metadata.read", "files.content.read", "sharing.read", "sharing.write" };
var redirect = DropboxOAuth2Helper.GetAuthorizeUri(OAuthResponseType.Code,
AppKey,
RedirectUri,
state: state,
tokenAccessType: TokenAccessType.Offline,
scopeList: scopeList,
includeGrantedScopes: IncludeGrantedScopes.None);
return Redirect(redirect.ToString());
[Authorize]
public async Task<ActionResult> AuthAsync(string code, string state)
{
try
{
var response = await DropboxOAuth2Helper.ProcessCodeFlowAsync(
code,
AppKey,
AppSecret,
RedirectUri);
TempData["AuthToken"] = response.AccessToken;
TempData["TokenExpires"] = response.ExpiresAt;
TempData["RefreshToken"] = response.RefreshToken;
_refreshToken = response.RefreshToken;
string? refUrl = TempData["Referrer"]?.ToString();
string? galleryItemId = TempData["GalleryItemId"]?.ToString();
if (!string.IsNullOrEmpty(refUrl) && refUrl.Contains("Add"))
{
return RedirectToAction("AddGalleryItem", "Gallery");
}
else if (!string.IsNullOrEmpty(refUrl) && refUrl.Contains("Edit"))
{
return RedirectToAction("EditGalleryItem", "Gallery", new { galleryItemId = galleryItemId });
}
return RedirectToAction("Index", "Home");
}
catch (Exception e)
{
var message = e.Message;
return RedirectToAction("Index");
}
}
SaveGalleryItem() - blows up on this call: await dbx.Sharing.CreateSharedLinkWithSettingsAsync
error: Invalid Grant
if (TempData != null && TempData.ContainsKey("RefreshToken"))
{
refreshToken = TempData["RefreshToken"]?.ToString();
}
using (var dbx = new DropboxClient(refreshToken))
{
var sharedLinkUrl = string.Empty;
var sharedLink = await dbx.Sharing.CreateSharedLinkWithSettingsAsync($"/Gourmet Philatelist/{ItemUrl}");
//(ItemUrl is the file name in the Dropbox folder).
if (sharedLink != null)
{
sharedLinkUrl = sharedLink.Url;
model.ImageUrl = sharedLinkUrl.Replace("dl=0", "raw=1");
}
}
I have been trying to do this for 3 days now with no success. I emailed Dropbox Support and they told me to try to find help in the Dropbox Community. Any help you can provide is greatly appreciated. Thank you.
Best Regards,
Debra Hodges for Bob Hodges Dropbox
