[evolution-data-server] GOA module: Run EWS autodiscovery asynchronously

[Milan Crha <mcrha src gnome org>]

commit ab7bd10026e035c49f12dd09ee2798abd62ae132
Author: Milan Crha <mcrha redhat com>
Date:   Thu Aug 15 08:24:54 2019 +0200

    GOA module: Run EWS autodiscovery asynchronously
    
    The autodiscovery does network I/O, which means it can block. The place
    where it is invoked is called from the main thread of the source registry
    process, which means, in case the server is unresponsive for whatever
    reason, the blocking call blocks also the source registry, making it
    unresponsive until the autodiscovery timeouts or others eds. To fix this,
    run the autodiscovery asynchronously instead.

 .../module-gnome-online-accounts.c                 | 96 +++++++++++++---------
 1 file changed, 55 insertions(+), 41 deletions(-)
---
diff --git a/src/modules/gnome-online-accounts/module-gnome-online-accounts.c 
b/src/modules/gnome-online-accounts/module-gnome-online-accounts.c
index 9bb994df1..1fd2a6ec8 100644
--- a/src/modules/gnome-online-accounts/module-gnome-online-accounts.c
+++ b/src/modules/gnome-online-accounts/module-gnome-online-accounts.c
@@ -246,59 +246,30 @@ gnome_online_accounts_new_source (EGnomeOnlineAccounts *extension)
 }
 
 static void
-gnome_online_accounts_config_exchange (EGnomeOnlineAccounts *extension,
-                                       ESource *source,
-                                       GoaObject *goa_object)
+goa_ews_autodiscover_done_cb (GObject *source_object,
+                             GAsyncResult *result,
+                             gpointer user_data)
 {
-       GoaExchange *goa_exchange;
+       GoaObject *goa_object;
+       ESource *source = user_data;
        ESourceExtension *source_extension;
        const gchar *extension_name;
        gchar *as_url = NULL;
        gchar *oab_url = NULL;
-       gpointer class;
        GError *error = NULL;
 
-       goa_exchange = goa_object_peek_exchange (goa_object);
-       if (goa_exchange == NULL)
-               return;
+       g_return_if_fail (GOA_IS_OBJECT (source_object));
+       g_return_if_fail (E_IS_SOURCE (source));
 
-       /* This should force the ESourceCamelEws type to be registered.
-        * It will also tell us if Evolution-EWS is even installed. */
-       class = g_type_class_ref (g_type_from_name ("EEwsBackend"));
-       if (class != NULL) {
-               g_type_class_unref (class);
-       } else {
-               g_critical (
-                       "%s: Could not locate EEwsBackendClass. "
-                       "Is Evolution-EWS installed?", G_STRFUNC);
-               return;
-       }
+       goa_object = GOA_OBJECT (source_object);
 
-       /* XXX GNOME Online Accounts already runs autodiscover to test
-        *     the user-entered values but doesn't share the discovered
-        *     URLs.  It only provides us a host name and expects us to
-        *     re-run autodiscover for ourselves.
-        *
-        *     So I've copied a slab of code from GOA which was in turn
-        *     copied from Evolution-EWS which does the autodiscovery.
-        *
-        *     I've already complained to Debarshi Ray about the lack
-        *     of useful info in GOA's Exchange interface so hopefully
-        *     it will someday publish discovered URLs and then we can
-        *     remove this hack. */
-
-       goa_ews_autodiscover_sync (
-               goa_object, &as_url, &oab_url, NULL, &error);
-
-       if (error != NULL) {
-               g_warning ("%s: %s", G_STRFUNC, error->message);
-               g_error_free (error);
+       if (!goa_ews_autodiscover_finish (goa_object, result, &as_url, &oab_url, &error) || !as_url) {
+               g_message ("Failed to autodiscover EWS data: %s", error ? error->message : "Unknown error");
+               g_clear_error (&error);
+               g_object_unref (source);
                return;
        }
 
-       g_return_if_fail (as_url != NULL);
-       g_return_if_fail (oab_url != NULL);
-
        /* XXX We don't have direct access to CamelEwsSettings from here
         *     since it's defined in Evolution-EWS.  But we can find out
         *     its extension name and set properties by name. */
@@ -345,10 +316,53 @@ gnome_online_accounts_config_exchange (EGnomeOnlineAccounts *extension,
                        G_STRFUNC, extension_name);
        }
 
+       g_object_unref (source);
        g_free (as_url);
        g_free (oab_url);
 }
 
+static void
+gnome_online_accounts_config_exchange (EGnomeOnlineAccounts *extension,
+                                       ESource *source,
+                                       GoaObject *goa_object)
+{
+       GoaExchange *goa_exchange;
+       gpointer class;
+
+       goa_exchange = goa_object_peek_exchange (goa_object);
+       if (goa_exchange == NULL)
+               return;
+
+       /* This should force the ESourceCamelEws type to be registered.
+        * It will also tell us if Evolution-EWS is even installed. */
+       class = g_type_class_ref (g_type_from_name ("EEwsBackend"));
+       if (class != NULL) {
+               g_type_class_unref (class);
+       } else {
+               g_critical (
+                       "%s: Could not locate EEwsBackendClass. "
+                       "Is Evolution-EWS installed?", G_STRFUNC);
+               return;
+       }
+
+       /* XXX GNOME Online Accounts already runs autodiscover to test
+        *     the user-entered values but doesn't share the discovered
+        *     URLs.  It only provides us a host name and expects us to
+        *     re-run autodiscover for ourselves.
+        *
+        *     So I've copied a slab of code from GOA which was in turn
+        *     copied from Evolution-EWS which does the autodiscovery.
+        *
+        *     I've already complained to Debarshi Ray about the lack
+        *     of useful info in GOA's Exchange interface so hopefully
+        *     it will someday publish discovered URLs and then we can
+        *     remove this hack. */
+
+       /* This function is called in the main thread and the autodiscovery
+          can block it, thus use the asynchronous/non-blocking version. */
+       goa_ews_autodiscover (goa_object, NULL, goa_ews_autodiscover_done_cb, g_object_ref (source));
+}
+
 static void
 gnome_online_accounts_config_imap (EGnomeOnlineAccounts *extension,
                                    ESource *source,