[couchdb] 01/01: Don't crash couch_index_server if the db isn't known yet

[rn...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

rnewson pushed a commit to branch couch_index_server_crash2
in repository https://gitbox.apache.org/repos/asf/couchdb.git

commit 7b6f806ad63eeb06d73c296232ff9f966247ae31
Author: Robert Newson <ro...@uk.ibm.com>
AuthorDate: Thu Aug 13 14:23:24 2020 +0100

    Don't crash couch_index_server if the db isn't known yet
    
    If a ddoc is added immediately after database creation (_users and
    _replicator when couchdb is used in a multi-tenant fashion), we can
    crash couch_index_server in handle_db_event, as mem3_shards:local
    throws an error.
---
 src/couch_index/src/couch_index_server.erl | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/couch_index/src/couch_index_server.erl b/src/couch_index/src/couch_index_server.erl
index 67f0f8c..6bebff2 100644
--- a/src/couch_index/src/couch_index_server.erl
+++ b/src/couch_index/src/couch_index_server.erl
@@ -284,7 +284,11 @@ handle_db_event(<<"shards/", _/binary>> = DbName, {ddoc_updated,
     DDocResult = couch_util:with_db(DbName, fun(Db) ->
         couch_db:open_doc(Db, DDocId, [ejson_body, ?ADMIN_CTX])
     end),
-    DbShards = [mem3:name(Sh) || Sh <- mem3:local_shards(mem3:dbname(DbName))],
+    LocalShards = try mem3:local_shards(mem3:dbname(DbName))
+        catch error:database_does_not_exist ->
+            []
+    end,
+    DbShards = [mem3:name(Sh) || Sh <- LocalShards],
     lists:foreach(fun(DbShard) ->
         lists:foreach(fun({_DbShard, {_DDocId, Sig}}) ->
             % check if there are other ddocs with the same Sig for the same db