Divide partitions amount all consumers. See wvanbergen#61

consumergroup/utils.go

@@ -32,28 +32,30 @@ func dividePartitionsBetweenConsumers(consumers kazoo.ConsumergroupInstanceList,
 
 	plen := len(partitions)
 	clen := len(consumers)
+	if clen == 0 {
+		return result
+	}
 
 	sort.Sort(partitions)
 	sort.Sort(consumers)
 
 	n := plen / clen
-	if plen%clen > 0 {
-		n++
-	}
+	m := plen % clen
+	p := 0
 	for i, consumer := range consumers {
-		first := i * n
-		if first > plen {
-			first = plen
+		first := p
+		last := first + n
+		if m > 0 && i > m {
+			last++
 		}
-
-		last := (i + 1) * n
 		if last > plen {
 			last = plen
 		}
 
 		for _, pl := range partitions[first:last] {
 			result[consumer.ID] = append(result[consumer.ID], pl.partition)
 		}
+		p = last
 	}
 
 	return result