[evolution-data-server] CalDAV: Claim not found objects during refresh as removed

[Milan Crha <mcrha src gnome org>]

commit c05a3374e614c3e9ec5baca0d545e3d76752bedc
Author: Milan Crha <mcrha redhat com>
Date:   Tue Feb 25 17:16:57 2020 +0100

    CalDAV: Claim not found objects during refresh as removed
    
    Noticed on Google server, which claims existing detached instances
    in the REPORT response, but then returns 404 Not Found responses
    when trying to get them.
    
    This change claims such objects as removed, which makes them gone also
    from the local cache.

 .../backends/caldav/e-cal-backend-caldav.c         | 89 ++++++++++++++++++----
 1 file changed, 75 insertions(+), 14 deletions(-)
---
diff --git a/src/calendar/backends/caldav/e-cal-backend-caldav.c 
b/src/calendar/backends/caldav/e-cal-backend-caldav.c
index c96f518b1..3f69c4e14 100644
--- a/src/calendar/backends/caldav/e-cal-backend-caldav.c
+++ b/src/calendar/backends/caldav/e-cal-backend-caldav.c
@@ -394,6 +394,11 @@ ecb_caldav_update_nfo_with_vcalendar (ECalMetaBackendInfo *nfo,
        }
 }
 
+typedef struct _MultigetData {
+       GSList *from_link;
+       GSList **out_removed_objects;
+} MultigetData;
+
 static gboolean
 ecb_caldav_multiget_response_cb (EWebDAVSession *webdav,
                                 xmlXPathContextPtr xpath_ctx,
@@ -403,9 +408,10 @@ ecb_caldav_multiget_response_cb (EWebDAVSession *webdav,
                                 guint status_code,
                                 gpointer user_data)
 {
-       GSList **from_link = user_data;
+       MultigetData *md = user_data;
 
-       g_return_val_if_fail (from_link != NULL, FALSE);
+       g_return_val_if_fail (md != NULL, FALSE);
+       g_return_val_if_fail (md->from_link != NULL, FALSE);
 
        if (!xpath_prop_prefix) {
                e_xml_xpath_context_register_namespaces (xpath_ctx, "C", E_WEBDAV_NS_CALDAV, NULL);
@@ -428,7 +434,7 @@ ecb_caldav_multiget_response_cb (EWebDAVSession *webdav,
                                if (uid) {
                                        GSList *link;
 
-                                       for (link = *from_link; link; link = g_slist_next (link)) {
+                                       for (link = md->from_link; link; link = g_slist_next (link)) {
                                                ECalMetaBackendInfo *nfo = link->data;
 
                                                if (!nfo)
@@ -437,8 +443,8 @@ ecb_caldav_multiget_response_cb (EWebDAVSession *webdav,
                                                if (g_strcmp0 (nfo->extra, href) == 0) {
                                                        /* If the server returns data in the same order as it 
had been requested,
                                                           then this speeds up lookup for the matching 
object. */
-                                                       if (link == *from_link)
-                                                               *from_link = g_slist_next (*from_link);
+                                                       if (link == md->from_link)
+                                                               md->from_link = g_slist_next (md->from_link);
 
                                                        ecb_caldav_update_nfo_with_vcalendar (nfo, vcalendar, 
etag);
 
@@ -458,7 +464,7 @@ ecb_caldav_multiget_response_cb (EWebDAVSession *webdav,
 
                g_return_val_if_fail (href != NULL, FALSE);
 
-               for (link = *from_link; link; link = g_slist_next (link)) {
+               for (link = md->from_link; link; link = g_slist_next (link)) {
                        ECalMetaBackendInfo *nfo = link->data;
 
                        if (!nfo)
@@ -467,10 +473,14 @@ ecb_caldav_multiget_response_cb (EWebDAVSession *webdav,
                        if (g_strcmp0 (nfo->extra, href) == 0) {
                                /* If the server returns data in the same order as it had been requested,
                                   then this speeds up lookup for the matching object. */
-                               if (link == *from_link)
-                                       *from_link = g_slist_next (*from_link);
+                               if (link == md->from_link)
+                                       md->from_link = g_slist_next (md->from_link);
+
+                               if (md->out_removed_objects)
+                                       *md->out_removed_objects = g_slist_prepend (*md->out_removed_objects, 
nfo);
+                               else
+                                       e_cal_meta_backend_info_free (nfo);
 
-                               e_cal_meta_backend_info_free (nfo);
                                link->data = NULL;
 
                                break;
@@ -486,6 +496,7 @@ ecb_caldav_multiget_from_sets_sync (ECalBackendCalDAV *cbdav,
                                    EWebDAVSession *webdav,
                                    GSList **in_link,
                                    GSList **set2,
+                                   GSList **out_removed_objects,
                                    GCancellable *cancellable,
                                    GError **error)
 {
@@ -590,8 +601,24 @@ ecb_caldav_multiget_from_sets_sync (ECalBackendCalDAV *cbdav,
                                g_free (new_uri);
                        }
 
-                       if (!success)
-                               success = e_webdav_session_get_data_sync (webdav, nfo->extra, NULL, &etag, 
&calendar_data, NULL, cancellable, error);
+                       if (!success) {
+                               GError *local_error = NULL;
+
+                               success = e_webdav_session_get_data_sync (webdav, nfo->extra, NULL, &etag, 
&calendar_data, NULL, cancellable, &local_error);
+
+                               if (!success && g_error_matches (local_error, SOUP_HTTP_ERROR, 
SOUP_STATUS_NOT_FOUND)) {
+                                       if (out_removed_objects)
+                                               *out_removed_objects = g_slist_prepend (*out_removed_objects, 
nfo);
+                                       else
+                                               e_cal_meta_backend_info_free (nfo);
+
+                                       link->data = NULL;
+                                       g_clear_error (&local_error);
+                                       continue;
+                               } else if (local_error) {
+                                       g_propagate_error (error, local_error);
+                               }
+                       }
 
                        if (success && calendar_data) {
                                ICalComponent *vcalendar;
@@ -628,10 +655,13 @@ ecb_caldav_multiget_from_sets_sync (ECalBackendCalDAV *cbdav,
 
        if (left_to_go != E_CALDAV_MAX_MULTIGET_AMOUNT &&
            !cbdav->priv->is_icloud && success) {
-               GSList *from_link = *in_link;
+               MultigetData md;
+
+               md.from_link = *in_link;
+               md.out_removed_objects = out_removed_objects;
 
                success = e_webdav_session_report_sync (webdav, NULL, NULL, xml,
-                       ecb_caldav_multiget_response_cb, &from_link, NULL, NULL, cancellable, error);
+                       ecb_caldav_multiget_response_cb, &md, NULL, NULL, cancellable, error);
        }
 
        g_object_unref (xml);
@@ -926,6 +956,7 @@ ecb_caldav_get_changes_sync (ECalMetaBackend *meta_backend,
        g_hash_table_destroy (known_items);
 
        if (success && (*out_created_objects || *out_modified_objects)) {
+               ECalCache *cal_cache = e_cal_meta_backend_ref_cache (meta_backend);
                GSList *link, *set2 = *out_modified_objects;
 
                if (*out_created_objects) {
@@ -936,8 +967,38 @@ ecb_caldav_get_changes_sync (ECalMetaBackend *meta_backend,
                }
 
                do {
-                       success = ecb_caldav_multiget_from_sets_sync (cbdav, webdav, &link, &set2, 
cancellable, &local_error);
+                       success = ecb_caldav_multiget_from_sets_sync (cbdav, webdav, &link, &set2, 
out_removed_objects, cancellable, &local_error);
                } while (success && link);
+
+               for (link = *out_created_objects; link; link = g_slist_next (link)) {
+                       ECalMetaBackendInfo *nfo = link->data;
+
+                       if (!nfo)
+                               continue;
+
+                       if (!nfo->uid || !*nfo->uid) {
+                               GSList *ids = NULL, *ilink = NULL;
+
+                               link->data = NULL;
+
+                               if (e_cal_cache_get_ids_with_extra (cal_cache, nfo->extra, &ids, cancellable, 
NULL)) {
+                                       for (ilink = ids; ilink; ilink = g_slist_next (ilink)) {
+                                               ECalComponentId *id = ilink->data;
+
+                                               if (id) {
+                                                       *out_removed_objects = g_slist_prepend 
(*out_removed_objects,
+                                                               e_cal_meta_backend_info_new 
(e_cal_component_id_get_uid (id), nfo->revision, NULL, nfo->extra));
+                                               }
+                                       }
+
+                                       g_slist_free_full (ids, e_cal_component_id_free);
+                               }
+
+                               e_cal_meta_backend_info_free (nfo);
+                       }
+               }
+
+               g_clear_object (&cal_cache);
        }
 
        if (local_error) {