create_if_missing doesn't always take effect

[nickva]

In the logs we see:

[warning] 2022-12-01T06:27:19.402535Z couchdb@couchdb-couchdb-1.couchdb-couchdb.drive-app.svc.cluster.local <0.1954.0> -------- mem3_sync shards/00000000-7fffffff/manifests-0038211.1669809395 couchdb@couchdb-couchdb-0.couchdb-couchdb.drive-app.svc.cluster.local {{rexi_EXIT,{{error,missing_target},[{mem3_util,get_or_create_db,2,[{file,[115,114,99,47,109,101,109,51,95,117,116,105,108,46,101,114,108]},{line,525}]},{mem3_rpc,load_checkpoint_rpc,4,[{file,[115,114,99,47,109,101,109,51,95,114,112,99,46,101,114,108]},{line,122}]},

load_rpc_checkpoint

couchdb/src/mem3/src/mem3_rpc.erl

Lines 107 to 110 in f13ceb4

	erlang:put(io_priority, {internal_repl, DbName}),
	case get_or_create_db(DbName, [?ADMIN_CTX]) of
	{ok, Db} ->
	TargetUUID = couch_db:get_uuid(Db),

calls get_or_create

couchdb/src/mem3/src/mem3_util.erl

Lines 606 to 612 in f13ceb4

	try
	Options1 = [{create_if_missing, true} | Options],
	Options2 = add_db_config_options(DbName, Options1),
	couch_db:open(DbName, Options2)
	catch
	error:database_does_not_exist ->
	throw({error, missing_target})

And there oddly enough, even with a [{create_if_missing, true}] we still catch error:database_does_not_exist error.

It could be from trying to load validation functions, security, shard doc, design docs or something of that type which blows up.

Perhaps?

couchdb/src/couch/src/couch_db.erl

Lines 977 to 979 in f13ceb4

	{'DOWN', Ref, _, _, {database_does_not_exist, _StackTrace}} ->
	ok = couch_server:close_db_if_idle(Db#db.name),
	erlang:error(database_does_not_exist);

But I don't see how'd call that from this context:

couchdb/src/couch/src/couch_server.erl

Lines 108 to 129 in f13ceb4

	open_int(DbName, Options0) ->
	Ctx = couch_util:get_value(user_ctx, Options0, #user_ctx{}),
	case ets:lookup(couch_dbs(DbName), DbName) of
	[#entry{db = Db0, lock = Lock} = Entry] when Lock =/= locked ->
	update_lru(DbName, Entry#entry.db_options),
	{ok, Db1} = couch_db:incref(Db0),
	couch_db:set_user_ctx(Db1, Ctx);
	_ ->
	Options = maybe_add_sys_db_callbacks(DbName, Options0),
	Timeout = couch_util:get_value(timeout, Options, infinity),
	Create = couch_util:get_value(create_if_missing, Options, false),
	case gen_server:call(couch_server(DbName), {open, DbName, Options}, Timeout) of
	{ok, Db0} ->
	{ok, Db1} = couch_db:incref(Db0),
	couch_db:set_user_ctx(Db1, Ctx);
	{not_found, no_db_file} when Create ->
	couch_log:warning("creating missing database: ~s", [DbName]),
	couch_server:create(DbName, Options);
	Error ->
	Error
	end
	end.