fts-solr: Avoid sending too large queries to Solr due to listing wanted mailboxes.

This is mainly a problem if there are a lot of mailboxes and "All Mails"
virtual mailbox. For now hardcoded to send max 10 mailboxes in the query,
afterwards it just returns matches in all the mailboxes and we'll filter out
the unwanted mailboxes.

diff --git a/src/plugins/fts-solr/fts-backend-solr.c b/src/plugins/fts-solr/fts-backend-solr.c
index 2359619f40be7a62032a0d1d85c1bb4bcb9bd350..f0e19e95743fc3e4c90d7a93874146a522ae31f4 100644 (file)
--- a/src/plugins/fts-solr/fts-backend-solr.c
+++ b/src/plugins/fts-solr/fts-backend-solr.c
@@ -26,6 +26,8 @@
    header fields as long as they're smaller than this */
 #define SOLR_HEADER_LINE_MAX_TRUNC_SIZE 1024
 
+#define SOLR_QUERY_MAX_MAILBOX_COUNT 10
+
 struct solr_fts_backend {
        struct fts_backend backend;
        struct solr_connection *solr_conn;
@@ -831,6 +833,7 @@ solr_search_multi(struct fts_backend *_backend, string_t *str,
        struct mailbox *box;
        const char *box_guid;
        unsigned int i, len;
+       bool search_all_mailboxes;
 
        /* use a separate filter query for selecting the mailbox. it shouldn't
           affect the score and there could be some caching benefits too. */
@@ -841,19 +844,26 @@ solr_search_multi(struct fts_backend *_backend, string_t *str,
                str_append(str, "%22%22");
 
        hash_table_create(&mailboxes, default_pool, 0, str_hash, strcmp);
-       str_append(str, "%2B(");
+       for (i = 0; boxes[i] != NULL; i++) ;
+       search_all_mailboxes = i > SOLR_QUERY_MAX_MAILBOX_COUNT;
+       if (!search_all_mailboxes)
+               str_append(str, "%2B(");
        len = str_len(str);
+
        for (i = 0; boxes[i] != NULL; i++) {
                if (fts_mailbox_get_guid(boxes[i], &box_guid) < 0)
                        continue;
 
-               if (str_len(str) != len)
-                       str_append(str, "+OR+");
-               str_printfa(str, "box:%s", box_guid);
+               if (!search_all_mailboxes) {
+                       if (str_len(str) != len)
+                               str_append(str, "+OR+");
+                       str_printfa(str, "box:%s", box_guid);
+               }
                hash_table_insert(mailboxes, t_strdup_noconst(box_guid),
                                  boxes[i]);
        }
-       str_append_c(str, ')');
+       if (!search_all_mailboxes)
+               str_append_c(str, ')');
 
        if (solr_connection_select(backend->solr_conn, str_c(str),
                                   result->pool, &solr_results) < 0) {
@@ -865,8 +875,10 @@ solr_search_multi(struct fts_backend *_backend, string_t *str,
        for (i = 0; solr_results[i] != NULL; i++) {
                box = hash_table_lookup(mailboxes, solr_results[i]->box_id);
                if (box == NULL) {
-                       i_warning("fts_solr: Lookup returned unexpected mailbox "
-                                 "with guid=%s", solr_results[i]->box_id);
+                       if (!search_all_mailboxes) {
+                               i_warning("fts_solr: Lookup returned unexpected mailbox "
+                                         "with guid=%s", solr_results[i]->box_id);
+                       }
                        continue;
                }
                fts_result = array_append_space(&fts_results);