backup from rbox -> mdbox :

[jrse]

dsync(t1): Warning: no value for metadata 'P' found
dsync(t1): Warning: no value for metadata 'O' found

[jrse]

Metadata 'O' = RBOX_METADATA_POP3_ORDER
Metadata 'P' = RBOX_METADATA_POP3_UIDL

Source of this warning is rbox_mail.cpp
rbox_mail_metadata_get(...)
...
rmail->rados_mail->get_metadata(key, &value);
if (!value.empty()) {
*value_r = i_strdup(value.c_str());
} else {
i_warning("no value for metadata '%c' found ", static_cast(key));
}
...

rbox_save.cpp
rbox_save_mail_set_metadata(...)
...
if (r_storage->config->is_mail_attribute(rbox_metadata_key::RBOX_METADATA_POP3_UIDL)) {
if (mdata->pop3_uidl != NULL) {
RadosMetadata xattr(rbox_metadata_key::RBOX_METADATA_POP3_UIDL, mdata->pop3_uidl);
mail_object->add_metadata(xattr);
}
}
if (r_storage->config->is_mail_attribute(rbox_metadata_key::RBOX_METADATA_POP3_ORDER)) {
if (mdata->pop3_order != 0) {
RadosMetadata xattr(rbox_metadata_key::RBOX_METADATA_POP3_ORDER, mdata->pop3_order);
mail_object->add_metadata(xattr);
}
}
...