cfg: check for temporary tubes in replicaset mode

In replicaset mode we cannot use temporary tubes.
Data on them will not be replicated and the correct
operation of the queue will be disrupted.

This patch will not allow creation of the temporary tube
if `in_replicaset == true` or will not allow to set
`in_replicaset = true` if temporary tubes exists.

Follows up #120

Author: 0x501D

queue/abstract.lua

@@ -577,6 +577,12 @@ function method.create_tube(tube_name, tube_type, opts)
         return queue.tube[tube_name]
     end
 
+    local replicaset_mode = queue.cfg['in_replicaset'] or false
+    if replicaset_mode and opts.temporary then
+        log.error("Cannot create temporary tube in replicaset mode")
+        return
+    end
+
     local driver = queue.driver[tube_type]
     if driver == nil then
         error("Unknown tube type " .. tostring(tube_type))
@@ -850,6 +856,23 @@ local function cfg(self, opts)
         opts['in_replicaset'] = false
     end
 
+    -- Temporary spaces are not allowed in replicaset mode.
+    if opts['in_replicaset'] == true and box.space._queue then
+        local temp_tubes = ""
+        for _, tube in box.space._queue:pairs() do
+            if tube[5].temporary then
+                temp_tubes = temp_tubes .. ', ' .. tube[1]
+            end
+        end
+
+        if #temp_tubes ~= 0 then
+            temp_tubes = temp_tubes:sub(3) -- Cut first ', '.
+            opts['in_replicaset'] = false
+            log.error('Queue: cannot set `in_replicaset = true`: '
+                .. 'temporary tube(s) exists: ' .. temp_tubes)
+        end
+    end
+
     -- Check all options before configuring so that
     -- the configuration is done transactionally.
     for key, val in pairs(opts) do