[gnome-online-accounts] flickr, oauth: Close the dialog if the user denied access

[Debarshi Ray <debarshir src gnome org>]

commit 7f1cb7e1c47d900547323cfdbd4131bfd8311fdc
Author: Debarshi Ray <debarshir gnome org>
Date:   Tue Aug 8 17:50:15 2017 +0200

    flickr, oauth: Close the dialog if the user denied access
    
    ... via the OAuth1 web page.
    
    Ever since Flickr was added, clicking the "NO, THANKS" widget in the
    web page has redirected to https://www.gnome.org/, which is specified
    as GNOME's website in Flickr's App Garden, instead of to the specified
    callback URI and/or returning an error. The click on this element
    cannot be intercepted because the "click" event handler is not being
    called (WebKit bug?). Current attempts to inspect that element breaks
    the WebKit inspector.
    
    Instead, let's also use https://www.gnome.org/ as the callback URI,
    and use the lack of a query when redirecting to it to close the window.
    It might need adjustments when there is a different OAuth1-based
    provider.

 src/goabackend/goaflickrprovider.c |    6 +++++-
 src/goabackend/goaoauthprovider.c  |   25 ++++++++++++++++++-------
 2 files changed, 23 insertions(+), 8 deletions(-)
---
diff --git a/src/goabackend/goaflickrprovider.c b/src/goabackend/goaflickrprovider.c
index 6c480ba..d986b37 100644
--- a/src/goabackend/goaflickrprovider.c
+++ b/src/goabackend/goaflickrprovider.c
@@ -101,7 +101,11 @@ get_token_uri (GoaOAuthProvider *oauth_provider)
 static const gchar *
 get_callback_uri (GoaOAuthProvider *oauth_provider)
 {
-  return "https://www.gnome.org/goa-1.0/oauth";;
+  /* Should match the URI specified in the Flickr App
+   * Garden in order to detect when the user denied access via
+   * the OAuth1 web page.
+   */
+  return "https://www.gnome.org/";;
 }
 
 /* ---------------------------------------------------------------------------------------------------- */
diff --git a/src/goabackend/goaoauthprovider.c b/src/goabackend/goaoauthprovider.c
index 58a083f..71bcad6 100644
--- a/src/goabackend/goaoauthprovider.c
+++ b/src/goabackend/goaoauthprovider.c
@@ -667,19 +667,30 @@ on_web_view_decide_policy (WebKitWebView            *web_view,
   uri = soup_uri_new (requested_uri);
   query = soup_uri_get_query (uri);
 
-  key_value_pairs = soup_form_decode (query);
+  if (query != NULL)
+    {
+      key_value_pairs = soup_form_decode (query);
+
+      data->oauth_verifier = g_strdup (g_hash_table_lookup (key_value_pairs, "oauth_verifier"));
+      if (data->oauth_verifier != NULL)
+        response_id = GTK_RESPONSE_OK;
+
+      g_hash_table_unref (key_value_pairs);
+    }
 
-  /* TODO: error handling? */
-  data->oauth_verifier = g_strdup (g_hash_table_lookup (key_value_pairs, "oauth_verifier"));
   if (data->oauth_verifier != NULL)
-    response_id = GTK_RESPONSE_OK;
+    goto ignore_request;
 
-  g_hash_table_unref (key_value_pairs);
+  /* TODO: The only OAuth1 provider is Flickr. It doesn't send any
+   * error code and only redirects to the URI specified in the Flickr
+   * App Garden. Re-evaluate when the situation changes.
+   */
+  response_id = GTK_RESPONSE_CANCEL;
   goto ignore_request;
 
  ignore_request:
-  if (response_id != GTK_RESPONSE_NONE)
-    gtk_dialog_response (data->dialog, response_id);
+  g_assert (response_id != GTK_RESPONSE_NONE);
+  gtk_dialog_response (data->dialog, response_id);
   webkit_policy_decision_ignore (decision);
   return TRUE;