[CalDAV] Try to search for event when not in local cache

CalDAV backend depends on local cache when a client ask for an event,
which is usually fine, but when it comes to a meeting invitations,
with which the server can add event to the calendar on its own,
the invitation might not be found in the cache, thus try whether
it's available on the remote machine, before reporting Object Not Found.

1 files changed, 240 insertions, 70 deletions

diff --git a/calendar/backends/caldav/e-cal-backend-caldav.c b/calendar/backends/caldav/e-cal-backend-caldav.c
index d707a560b..2ffabef43 100644
--- a/calendar/backends/caldav/e-cal-backend-caldav.c
+++ b/calendar/backends/caldav/e-cal-backend-caldav.c
@@ -303,6 +303,7 @@ static void caldav_source_changed_cb (ESource *source, ECalBackendCalDAV *cbdav)
 
 static gboolean remove_comp_from_cache (ECalBackendCalDAV *cbdav, const gchar *uid, const gchar *rid);
 static gboolean put_comp_to_cache (ECalBackendCalDAV *cbdav, icalcomponent *icalcomp, const gchar *href, const gchar *etag);
+static void put_server_comp_to_cache (ECalBackendCalDAV *cbdav, icalcomponent *icomp, const gchar *href, const gchar *etag, GTree *c_uid2complist);
 
 /* ************************************************************************* */
 /* Misc. utility functions */
@@ -1461,6 +1462,150 @@ caldav_server_list_objects (ECalBackendCalDAV *cbdav,
 }
 
 static gboolean
+caldav_server_query_for_uid (ECalBackendCalDAV *cbdav,
+			     const gchar *uid,
+			     GCancellable *cancellable,
+			     GError **error)
+{
+	SoupMessage *message;
+	xmlOutputBufferPtr buf;
+	xmlNodePtr node;
+	xmlNodePtr sn;
+	xmlNodePtr root;
+	xmlDocPtr doc;
+	xmlNsPtr nsdav;
+	xmlNsPtr nscd;
+	gconstpointer buf_content;
+	gsize buf_size;
+	gboolean result = FALSE;
+	gint ii, len = 0;
+	CalDAVObject *objs = NULL, *object;
+
+	g_return_val_if_fail (cbdav != NULL, FALSE);
+	g_return_val_if_fail (E_IS_CAL_BACKEND_CALDAV (cbdav), FALSE);
+	g_return_val_if_fail (uid && *uid, FALSE);
+
+	/* Allocate the soup message */
+	message = soup_message_new ("REPORT", cbdav->priv->uri);
+	if (message == NULL)
+		return FALSE;
+
+	/* Maybe we should just do a g_strdup_printf here? */
+	/* Prepare request body */
+	doc = xmlNewDoc ((xmlChar *) "1.0");
+	root = xmlNewDocNode (doc, NULL, (xmlChar *) "calendar-query", NULL);
+	nscd = xmlNewNs (root, (xmlChar *) "urn:ietf:params:xml:ns:caldav", (xmlChar *) "C");
+	xmlSetNs (root, nscd);
+	xmlDocSetRootElement (doc, root);
+
+	/* Add webdav tags */
+	nsdav = xmlNewNs (root, (xmlChar *) "DAV:", (xmlChar *) "D");
+	node = xmlNewTextChild (root, nsdav, (xmlChar *) "prop", NULL);
+	xmlNewTextChild (node, nsdav, (xmlChar *) "getetag", NULL);
+	xmlNewTextChild (node, nscd, (xmlChar *) "calendar-data", NULL);
+
+	node = xmlNewTextChild (root, nscd, (xmlChar *) "filter", NULL);
+	node = xmlNewTextChild (node, nscd, (xmlChar *) "comp-filter", NULL);
+	xmlSetProp (node, (xmlChar *) "name", (xmlChar *) "VCALENDAR");
+
+	sn = xmlNewTextChild (node, nscd, (xmlChar *) "comp-filter", NULL);
+	switch (e_cal_backend_get_kind (E_CAL_BACKEND (cbdav))) {
+		default:
+		case ICAL_VEVENT_COMPONENT:
+			xmlSetProp (sn, (xmlChar *) "name", (xmlChar *) "VEVENT");
+			break;
+		case ICAL_VJOURNAL_COMPONENT:
+			xmlSetProp (sn, (xmlChar *) "name", (xmlChar *) "VJOURNAL");
+			break;
+		case ICAL_VTODO_COMPONENT:
+			xmlSetProp (sn, (xmlChar *) "name", (xmlChar *) "VTODO");
+			break;
+	}
+
+	node = xmlNewTextChild (sn, nscd, (xmlChar *) "prop-filter", NULL);
+	xmlSetProp (node, (xmlChar *) "name", (xmlChar *) "UID");
+
+	sn = xmlNewTextChild (node, nscd, (xmlChar *) "text-match", NULL);
+	xmlSetProp (sn, (xmlChar *) "collation", (xmlChar *) "i;octet");
+	xmlNodeSetContent (sn, (xmlChar *) uid);
+
+	buf = xmlAllocOutputBuffer (NULL);
+	xmlNodeDumpOutput (buf, doc, root, 0, 1, NULL);
+	xmlOutputBufferFlush (buf);
+
+	/* Prepare the soup message */
+	soup_message_headers_append (
+		message->request_headers,
+		"User-Agent", "Evolution/" VERSION);
+	soup_message_headers_append (
+		message->request_headers,
+		"Depth", "1");
+
+	buf_content = compat_libxml_output_buffer_get_content (buf, &buf_size);
+	soup_message_set_request (
+		message,
+		"application/xml",
+		SOUP_MEMORY_COPY,
+		buf_content, buf_size);
+
+	/* Send the request now */
+	send_and_handle_redirection (cbdav->priv->session, message, NULL);
+
+	/* Clean up the memory */
+	xmlOutputBufferClose (buf);
+	xmlFreeDoc (doc);
+
+	/* Check the result */
+	if (message->status_code != 207) {
+		switch (message->status_code) {
+		case SOUP_STATUS_CANT_CONNECT:
+		case SOUP_STATUS_CANT_CONNECT_PROXY:
+			cbdav->priv->opened = FALSE;
+			update_slave_cmd (cbdav->priv, SLAVE_SHOULD_SLEEP);
+			cbdav->priv->read_only = TRUE;
+			e_cal_backend_notify_readonly (
+				E_CAL_BACKEND (cbdav), cbdav->priv->read_only);
+			break;
+		case 401:
+			caldav_authenticate (cbdav, TRUE, NULL, NULL);
+			break;
+		default:
+			g_warning ("Server did not response with 207, but with code %d (%s)", message->status_code, soup_status_get_phrase (message->status_code) ? soup_status_get_phrase (message->status_code) : "Unknown code");
+			break;
+		}
+
+		g_object_unref (message);
+		return FALSE;
+	}
+
+	/* Parse the response body */
+	if (parse_report_response (message, &objs, &len)) {
+		result = TRUE;
+
+		for (ii = 0, object = objs; ii < len; ii++, object++) {
+			if (object->status == 200 && object->href && object->etag && object->cdata && *object->cdata) {
+				icalcomponent *icomp = icalparser_parse_string (object->cdata);
+
+				if (icomp) {
+					put_server_comp_to_cache (cbdav, icomp, object->href, object->etag, NULL);
+					icalcomponent_free (icomp);
+				}
+			}
+
+			/* these free immediately */
+			caldav_object_free (object, FALSE);
+		}
+
+		/* cache update done for fetched items */
+		g_free (objs);
+	}
+
+	g_object_unref (message);
+
+	return result;
+}
+
+static gboolean
 caldav_server_download_attachment (ECalBackendCalDAV *cbdav,
                                    const gchar *attachment_uri,
                                    gchar **content,
@@ -2022,7 +2167,6 @@ synchronize_cache (ECalBackendCalDAV *cbdav,
                    time_t start_time,
                    time_t end_time)
 {
-	ECalBackend *bkend;
 	CalDAVObject *sobjs, *object;
 	GSList *c_objs, *c_iter; /* list of all items known from our cache */
 	GTree *c_uid2complist;  /* cache components list (with detached instances) sorted by (master's) uid */
@@ -2035,7 +2179,6 @@ synchronize_cache (ECalBackendCalDAV *cbdav,
 		return;
 	}
 
-	bkend  = E_CAL_BACKEND (cbdav);
 	len    = 0;
 	sobjs  = NULL;
 
@@ -2195,74 +2338,7 @@ synchronize_cache (ECalBackendCalDAV *cbdav,
 					icalcomponent *icomp = icalparser_parse_string (object->cdata);
 
 					if (icomp) {
-						icalcomponent_kind kind = icalcomponent_isa (icomp);
-
-						extract_timezones (cbdav, icomp);
-
-						if (kind == ICAL_VCALENDAR_COMPONENT) {
-							icalcomponent *subcomp;
-
-							kind = e_cal_backend_get_kind (bkend);
-
-							for (subcomp = icalcomponent_get_first_component (icomp, kind);
-							     subcomp;
-							     subcomp = icalcomponent_get_next_component (icomp, kind)) {
-								ECalComponent *new_comp, *old_comp;
-
-								convert_to_url_attachment (cbdav, subcomp);
-								new_comp = e_cal_component_new ();
-								if (e_cal_component_set_icalcomponent (new_comp, icalcomponent_new_clone (subcomp))) {
-									const gchar *uid = NULL;
-									struct cache_comp_list *ccl;
-
-									e_cal_component_get_uid (new_comp, &uid);
-									if (!uid) {
-										g_warning ("%s: no UID on component!", G_STRFUNC);
-										g_object_unref (new_comp);
-										continue;
-									}
-
-									ecalcomp_set_href (new_comp, object->href);
-									ecalcomp_set_etag (new_comp, object->etag);
-
-									old_comp = NULL;
-									ccl = g_tree_lookup (c_uid2complist, uid);
-									if (ccl) {
-										gchar *nc_rid = e_cal_component_get_recurid_as_string (new_comp);
-										GSList *p;
-
-										for (p = ccl->slist; p && !old_comp; p = p->next) {
-											gchar *oc_rid;
-
-											old_comp = p->data;
-
-											oc_rid = e_cal_component_get_recurid_as_string (old_comp);
-											if (g_strcmp0 (nc_rid, oc_rid) != 0) {
-												old_comp = NULL;
-											}
-
-											g_free (oc_rid);
-										}
-
-										g_free (nc_rid);
-									}
-
-									put_component_to_store (cbdav, new_comp);
-
-									if (old_comp == NULL) {
-										e_cal_backend_notify_component_created (bkend, new_comp);
-									} else {
-										e_cal_backend_notify_component_modified (bkend, old_comp, new_comp);
-
-										ccl->slist = g_slist_remove (ccl->slist, old_comp);
-										g_object_unref (old_comp);
-									}
-								}
-
-								g_object_unref (new_comp);
-							}
-						}
-
+						put_server_comp_to_cache (cbdav, icomp, object->href, object->etag, c_uid2complist);
 						icalcomponent_free (icomp);
 					}
 				}
@@ -2994,6 +3070,93 @@ get_comp_from_cache (ECalBackendCalDAV *cbdav,
 	return icalcomp;
 }
 
+static void
+put_server_comp_to_cache (ECalBackendCalDAV *cbdav,
+			  icalcomponent *icomp,
+			  const gchar *href,
+			  const gchar *etag,
+			  GTree *c_uid2complist)
+{
+	icalcomponent_kind kind;
+	ECalBackend *cal_backend;
+
+	g_return_if_fail (cbdav != NULL);
+	g_return_if_fail (icomp != NULL);
+
+	cal_backend = E_CAL_BACKEND (cbdav);
+	kind = icalcomponent_isa (icomp);
+	extract_timezones (cbdav, icomp);
+
+	if (kind == ICAL_VCALENDAR_COMPONENT) {
+		icalcomponent *subcomp;
+
+		kind = e_cal_backend_get_kind (cal_backend);
+
+		for (subcomp = icalcomponent_get_first_component (icomp, kind);
+		     subcomp;
+		     subcomp = icalcomponent_get_next_component (icomp, kind)) {
+			ECalComponent *new_comp, *old_comp;
+
+			convert_to_url_attachment (cbdav, subcomp);
+			new_comp = e_cal_component_new ();
+			if (e_cal_component_set_icalcomponent (new_comp, icalcomponent_new_clone (subcomp))) {
+				const gchar *uid = NULL;
+				struct cache_comp_list *ccl;
+
+				e_cal_component_get_uid (new_comp, &uid);
+				if (!uid) {
+					g_warning ("%s: no UID on component!", G_STRFUNC);
+					g_object_unref (new_comp);
+					continue;
+				}
+
+				if (href)
+					ecalcomp_set_href (new_comp, href);
+				if (etag)
+					ecalcomp_set_etag (new_comp, etag);
+
+				old_comp = NULL;
+				if (c_uid2complist) {
+					ccl = g_tree_lookup (c_uid2complist, uid);
+					if (ccl) {
+						gchar *nc_rid = e_cal_component_get_recurid_as_string (new_comp);
+						GSList *p;
+
+						for (p = ccl->slist; p && !old_comp; p = p->next) {
+							gchar *oc_rid;
+
+							old_comp = p->data;
+
+							oc_rid = e_cal_component_get_recurid_as_string (old_comp);
+							if (g_strcmp0 (nc_rid, oc_rid) != 0) {
+								old_comp = NULL;
+							}
+
+							g_free (oc_rid);
+						}
+
+						g_free (nc_rid);
+					}
+				}
+
+				put_component_to_store (cbdav, new_comp);
+
+				if (old_comp == NULL) {
+					e_cal_backend_notify_component_created (cal_backend, new_comp);
+				} else {
+					e_cal_backend_notify_component_modified (cal_backend, old_comp, new_comp);
+
+					if (ccl)
+						ccl->slist = g_slist_remove (ccl->slist, old_comp);
+					g_object_unref (old_comp);
+				}
+			}
+
+			g_object_unref (new_comp);
+		}
+	}
+}
+
 static gboolean
 put_comp_to_cache (ECalBackendCalDAV *cbdav,
                    icalcomponent *icalcomp,
@@ -4452,6 +4615,13 @@ caldav_get_object (ECalBackendSync *backend,
 	*object = NULL;
 	icalcomp = get_comp_from_cache (cbdav, uid, rid, NULL, NULL);
 
+	if (!icalcomp && e_backend_get_online (E_BACKEND (backend))) {
+		/* try to fetch from the server, maybe the event was received only recently */
+		if (caldav_server_query_for_uid (cbdav, uid, cancellable, NULL)) {
+			icalcomp = get_comp_from_cache (cbdav, uid, rid, NULL, NULL);
+		}
+	}
+
 	if (!icalcomp) {
 		g_propagate_error (perror, EDC_ERROR (ObjectNotFound));
 		return;