[evolution-data-server] I#1348 - WebDAVCollectionBackend: Removes sources on server error

[Milan Crha <mcrha src gnome org>]

commit 8ba112aaa59e650ab4bb6dcd3e32f2a9745ec54a
Author: Milan Crha <mcrha redhat com>
Date:   Fri Apr 29 12:49:58 2022 +0200

    I#1348 - WebDAVCollectionBackend: Removes sources on server error
    
    Closes https://gitlab.gnome.org/GNOME/evolution/-/issues/1348

 src/libebackend/e-webdav-collection-backend.c | 60 ++++++++++++++++++++++++++-
 1 file changed, 58 insertions(+), 2 deletions(-)
---
diff --git a/src/libebackend/e-webdav-collection-backend.c b/src/libebackend/e-webdav-collection-backend.c
index b99f17504..e4301e66f 100644
--- a/src/libebackend/e-webdav-collection-backend.c
+++ b/src/libebackend/e-webdav-collection-backend.c
@@ -57,6 +57,19 @@ webdav_collection_add_uid_to_hashtable (gpointer source,
        g_hash_table_insert (known_sources, rid, uid);
 }
 
+static gboolean
+webdav_collection_debug_enabled (void)
+{
+       static gint enabled = -1;
+
+       if (enabled == -1) {
+               const gchar *envval = g_getenv ("WEBDAV_DEBUG");
+               enabled = envval && *envval && g_strcmp0 (envval, "0") != 0 ? 1 : 0;
+       }
+
+       return enabled == 1;
+}
+
 typedef struct _RemoveSourcesData {
        ESourceRegistryServer *server;
        EWebDAVCollectionBackend *webdav_backend;
@@ -75,8 +88,13 @@ webdav_collection_remove_unknown_sources_cb (gpointer resource_id,
        source = e_source_registry_server_ref_source (rsd->server, uid);
 
        if (source) {
-               if (!e_webdav_collection_backend_is_custom_source (rsd->webdav_backend, source))
+               if (!e_webdav_collection_backend_is_custom_source (rsd->webdav_backend, source)) {
+                       if (webdav_collection_debug_enabled ()) {
+                               e_util_debug_print ("WEBDAV", "   %p: Going to remove previously known source 
'%s' (%s)\n", rsd->webdav_backend,
+                                       e_source_get_display_name (source), e_source_get_uid (source));
+                       }
                        e_source_remove_sync (source, NULL, NULL);
+               }
 
                g_object_unref (source);
        }
@@ -571,6 +589,9 @@ e_webdav_collection_backend_discover_sync (EWebDAVCollectionBackend *webdav_back
        g_list_foreach (sources, webdav_collection_add_uid_to_hashtable, known_sources);
        g_list_free_full (sources, g_object_unref);
 
+       if (webdav_collection_debug_enabled ())
+               e_util_debug_print ("WEBDAV", "%p: This is '%s' (%s)\n", webdav_backend, 
e_source_get_display_name (source), e_source_get_uid (source));
+
        server = e_collection_backend_ref_server (collection);
 
        if (e_source_collection_get_calendar_enabled (collection_extension) && calendar_url &&
@@ -589,9 +610,13 @@ e_webdav_collection_backend_discover_sync (EWebDAVCollectionBackend *webdav_back
 
                webdav_collection_process_discovered_sources (collection, discovered_sources, known_sources, 
source_types, G_N_ELEMENTS (source_types));
 
+               if (webdav_collection_debug_enabled ())
+                       e_util_debug_print ("WEBDAV", "%p: Received %u calendars from '%s'\n", 
webdav_backend, g_slist_length (discovered_sources), calendar_url);
+
                e_webdav_discover_free_discovered_sources (discovered_sources);
                discovered_sources = NULL;
                any_success = TRUE;
+       /* Prevent lost of already known calendars when the discover failed */
        } else if (local_error) {
                RemoveSourceTypesData rstd;
 
@@ -599,6 +624,17 @@ e_webdav_collection_backend_discover_sync (EWebDAVCollectionBackend *webdav_back
                rstd.calendars = TRUE;
 
                g_hash_table_foreach_remove (known_sources, webdav_collection_remove_source_types_cb, &rstd);
+
+               if (webdav_collection_debug_enabled () &&
+                   (!credentials_empty || (
+                    !g_error_matches (local_error, SOUP_HTTP_ERROR, SOUP_STATUS_UNAUTHORIZED) &&
+                    !g_error_matches (local_error, SOUP_HTTP_ERROR, SOUP_STATUS_FORBIDDEN))))
+                       e_util_debug_print ("WEBDAV", "%p: Failed to get calendars from '%s': %s\n", 
webdav_backend, calendar_url, local_error->message);
+       } else if (e_source_collection_get_calendar_enabled (collection_extension) && calendar_url) {
+               if (webdav_collection_debug_enabled ()) {
+                       e_util_debug_print ("WEBDAV", "%p: Failed to get calendars from '%s': %s\n", 
webdav_backend, calendar_url,
+                               g_cancellable_is_cancelled (cancellable) ? "Is cancelled" : "Unknown error");
+               }
        }
 
        if (!local_error && e_source_collection_get_contacts_enabled (collection_extension) && contacts_url &&
@@ -612,16 +648,31 @@ e_webdav_collection_backend_discover_sync (EWebDAVCollectionBackend *webdav_back
 
                webdav_collection_process_discovered_sources (collection, discovered_sources, known_sources, 
source_types, G_N_ELEMENTS (source_types));
 
+               if (webdav_collection_debug_enabled ())
+                       e_util_debug_print ("WEBDAV", "%p: Received %u books from '%s'\n", webdav_backend, 
g_slist_length (discovered_sources), contacts_url);
+
                e_webdav_discover_free_discovered_sources (discovered_sources);
                discovered_sources = NULL;
                any_success = TRUE;
-       } else if (any_success && local_error) {
+       /* Prevent lost of already known address books when the discover failed */
+       } else if (local_error) {
                RemoveSourceTypesData rstd;
 
                rstd.server = server;
                rstd.calendars = FALSE;
 
                g_hash_table_foreach_remove (known_sources, webdav_collection_remove_source_types_cb, &rstd);
+
+               if (webdav_collection_debug_enabled () &&
+                   (!credentials_empty || (
+                    !g_error_matches (local_error, SOUP_HTTP_ERROR, SOUP_STATUS_UNAUTHORIZED) &&
+                    !g_error_matches (local_error, SOUP_HTTP_ERROR, SOUP_STATUS_FORBIDDEN))))
+                       e_util_debug_print ("WEBDAV", "%p: Failed to get books from '%s': %s\n", 
webdav_backend, contacts_url, local_error->message);
+       } else if (e_source_collection_get_contacts_enabled (collection_extension) && contacts_url) {
+               if (webdav_collection_debug_enabled ()) {
+                       e_util_debug_print ("WEBDAV", "%p: Failed to get books from '%s': %s\n", 
webdav_backend, contacts_url,
+                               g_cancellable_is_cancelled (cancellable) ? "Is cancelled" : "Unknown error");
+               }
        }
 
        if (any_success && server && !g_cancellable_is_cancelled (cancellable)) {
@@ -630,6 +681,11 @@ e_webdav_collection_backend_discover_sync (EWebDAVCollectionBackend *webdav_back
                rsd.server = server;
                rsd.webdav_backend = webdav_backend;
 
+               if (webdav_collection_debug_enabled () && g_hash_table_size (known_sources)) {
+                       e_util_debug_print ("WEBDAV", "%p: Have %u leftover previously known sources\n", 
webdav_backend,
+                               g_hash_table_size (known_sources));
+               }
+
                g_hash_table_foreach (known_sources, webdav_collection_remove_unknown_sources_cb, &rsd);
 
                g_clear_error (&local_error);