fix: Add guards for converting Stat interface (might be nil)

Change-Id: I54cd9ca6fb6607a70031ba5e6318a9ea58db7e6c
Signed-off-by: Ondrej Fabry <ofabry@cisco.com>

diff --git a/core/stats.go b/core/stats.go
index 23b3848..2a9e964 100644 (file)
--- a/core/stats.go
+++ b/core/stats.go
@@ -166,7 +166,7 @@ func (c *StatsConnection) updateStats(statDir **adapter.StatDir, patterns ...str
                } else if err == adapter.ErrStatsDirStale || err == adapter.ErrStatsDataBusy {
                        // retrying
                        if r > 1 {
-                               log.Debugln("sleeping for %v before next try", RetryUpdateDelay)
+                               log.Debugf("sleeping for %v before next try", RetryUpdateDelay)
                                time.Sleep(RetryUpdateDelay)
                        }
                } else {
@@ -255,23 +255,25 @@ func (c *StatsConnection) GetNodeStats(nodeStats *api.NodeStats) (err error) {
                }
        }
        perNode := func(stat adapter.StatEntry, fn func(*api.NodeCounters, uint64)) {
-               s := stat.Data.(adapter.SimpleCounterStat)
-               prepNodes(len(s[0]))
-               for i := range nodeStats.Nodes {
-                       val := adapter.ReduceSimpleCounterStatIndex(s, i)
-                       fn(&nodeStats.Nodes[i], val)
+               if s, ok := stat.Data.(adapter.SimpleCounterStat); ok {
+                       prepNodes(len(s[0]))
+                       for i := range nodeStats.Nodes {
+                               val := adapter.ReduceSimpleCounterStatIndex(s, i)
+                               fn(&nodeStats.Nodes[i], val)
+                       }
                }
        }
 
        for _, stat := range c.nodeStatsData.Entries {
                switch string(stat.Name) {
                case NodeStats_Names:
-                       stat := stat.Data.(adapter.NameStat)
-                       prepNodes(len(stat))
-                       for i, nc := range nodeStats.Nodes {
-                               if nc.NodeName != string(stat[i]) {
-                                       nc.NodeName = string(stat[i])
-                                       nodeStats.Nodes[i] = nc
+                       if stat, ok := stat.Data.(adapter.NameStat); ok {
+                               prepNodes(len(stat))
+                               for i, nc := range nodeStats.Nodes {
+                                       if nc.NodeName != string(stat[i]) {
+                                               nc.NodeName = string(stat[i])
+                                               nodeStats.Nodes[i] = nc
+                                       }
                                }
                        }
                case NodeStats_Clocks:
@@ -311,31 +313,34 @@ func (c *StatsConnection) GetInterfaceStats(ifaceStats *api.InterfaceStats) (err
                }
        }
        perNode := func(stat adapter.StatEntry, fn func(*api.InterfaceCounters, uint64)) {
-               s := stat.Data.(adapter.SimpleCounterStat)
-               prep(len(s[0]))
-               for i := range ifaceStats.Interfaces {
-                       val := adapter.ReduceSimpleCounterStatIndex(s, i)
-                       fn(&ifaceStats.Interfaces[i], val)
+               if s, ok := stat.Data.(adapter.SimpleCounterStat); ok {
+                       prep(len(s[0]))
+                       for i := range ifaceStats.Interfaces {
+                               val := adapter.ReduceSimpleCounterStatIndex(s, i)
+                               fn(&ifaceStats.Interfaces[i], val)
+                       }
                }
        }
        perNodeComb := func(stat adapter.StatEntry, fn func(*api.InterfaceCounters, [2]uint64)) {
-               s := stat.Data.(adapter.CombinedCounterStat)
-               prep(len(s[0]))
-               for i := range ifaceStats.Interfaces {
-                       val := adapter.ReduceCombinedCounterStatIndex(s, i)
-                       fn(&ifaceStats.Interfaces[i], val)
+               if s, ok := stat.Data.(adapter.CombinedCounterStat); ok {
+                       prep(len(s[0]))
+                       for i := range ifaceStats.Interfaces {
+                               val := adapter.ReduceCombinedCounterStatIndex(s, i)
+                               fn(&ifaceStats.Interfaces[i], val)
+                       }
                }
        }
 
        for _, stat := range c.ifaceStatsData.Entries {
                switch string(stat.Name) {
                case InterfaceStats_Names:
-                       stat := stat.Data.(adapter.NameStat)
-                       prep(len(stat))
-                       for i, nc := range ifaceStats.Interfaces {
-                               if nc.InterfaceName != string(stat[i]) {
-                                       nc.InterfaceName = string(stat[i])
-                                       ifaceStats.Interfaces[i] = nc
+                       if stat, ok := stat.Data.(adapter.NameStat); ok {
+                               prep(len(stat))
+                               for i, nc := range ifaceStats.Interfaces {
+                                       if nc.InterfaceName != string(stat[i]) {
+                                               nc.InterfaceName = string(stat[i])
+                                               ifaceStats.Interfaces[i] = nc
+                                       }
                                }
                        }
                case InterfaceStats_Drops: