lib/thread-fp: factor out query expansion, rewrite in Xapian

[notmuch] / lib / query.cc

diff --git a/lib/query.cc b/lib/query.cc
index 87ee18fc0c8124c35ac0d06a84a7445d7b4c9fd8..b0937fcc97ed3eefa4fb51881ebc4159843bb575 100644 (file)
--- a/lib/query.cc
+++ b/lib/query.cc
@@ -821,3 +821,51 @@ notmuch_query_get_database (const notmuch_query_t *query)
 {
     return query->notmuch;
 }
+
+notmuch_status_t
+_notmuch_query_expand (notmuch_database_t *notmuch, const char *field, Xapian::Query subquery,
+                      Xapian::Query &output, std::string &msg)
+{
+    std::set<std::string> terms;
+    const std::string term_prefix =  _find_prefix (field);
+
+    if (_debug_query ()) {
+       fprintf (stderr, "Expanding subquery:\n%s\n",
+                subquery.get_description ().c_str ());
+    }
+
+    try {
+       Xapian::Enquire enquire (*notmuch->xapian_db);
+       Xapian::MSet mset;
+
+       enquire.set_weighting_scheme (Xapian::BoolWeight ());
+       enquire.set_query (subquery);
+
+       mset = enquire.get_mset (0, notmuch->xapian_db->get_doccount ());
+
+       for (Xapian::MSetIterator iterator = mset.begin (); iterator != mset.end (); iterator++) {
+           Xapian::docid doc_id = *iterator;
+           Xapian::Document doc = notmuch->xapian_db->get_document (doc_id);
+           Xapian::TermIterator i = doc.termlist_begin ();
+
+           for (i.skip_to (term_prefix);
+                i != doc.termlist_end () && ((*i).rfind (term_prefix, 0) == 0); i++) {
+               terms.insert (*i);
+           }
+       }
+       output = Xapian::Query (Xapian::Query::OP_OR, terms.begin (), terms.end ());
+       if (_debug_query ()) {
+           fprintf (stderr, "Expanded query:\n%s\n",
+                    subquery.get_description ().c_str ());
+       }
+
+    } catch (const Xapian::Error &error) {
+       _notmuch_database_log (notmuch,
+                              "A Xapian exception occurred expanding query: %s\n",
+                              error.get_msg ().c_str ());
+       msg = error.get_msg ();
+       return NOTMUCH_STATUS_XAPIAN_EXCEPTION;
+    }
+
+    return NOTMUCH_STATUS_SUCCESS;
+}