cmd: address errcheck warnings

The following ones:

internal/storage/redis/redis.go:106:14: Error return value of `s.conn.Send` is not checked (errcheck)
		s.conn.Send("LPUSH", s.redisKey, seriesToFlush)
		           ^
internal/healthz/healthz.go:25:9: Error return value of `w.Write` is not checked (errcheck)
	w.Write([]byte("ok"))
	       ^
internal/api/handler.go:132:9: Error return value of `w.Write` is not checked (errcheck)
	w.Write(out)
	       ^
internal/storage/bigquery/client/example/example.go:43:17: Error return value of `c.PrintDatasets` is not checked (errcheck)
	c.PrintDatasets()
	               ^
cadvisor.go:105:10: Error return value of `flag.Set` is not checked (errcheck)
	flag.Set("v", "2")
	        ^

Signed-off-by: Kir Kolyshkin <[email protected]>

Author: kolyshkin

cmd/cadvisor.go

@@ -102,7 +102,7 @@ func init() {
 	flag.Var(&enableMetrics, "enable_metrics", fmt.Sprintf("comma-separated list of `metrics` to be enabled. If set, overrides 'disable_metrics'. Options are %s.", optstr))
 
 	// Default logging verbosity to V(2)
-	flag.Set("v", "2")
+	_ = flag.Set("v", "2")
 }
 
 func main() {

cmd/internal/api/handler.go

@@ -129,8 +129,8 @@ func writeResult(res interface{}, w http.ResponseWriter) error {
 	}
 
 	w.Header().Set("Content-Type", "application/json")
-	w.Write(out)
-	return nil
+	_, err = w.Write(out)
+	return err
 
 }
 

cmd/internal/healthz/healthz.go

@@ -22,7 +22,7 @@ import (
 
 func handleHealthz(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusOK)
-	w.Write([]byte("ok"))
+	_, _ = w.Write([]byte("ok"))
 }
 
 // Register simple HTTP /healthz handler to return "ok".

cmd/internal/storage/bigquery/client/example/example.go

@@ -40,7 +40,10 @@ func main() {
 		panic(err)
 	}
 
-	c.PrintDatasets()
+	err = c.PrintDatasets()
+	if err != nil {
+		panic(err)
+	}
 
 	// Create a new dataset.
 	err = c.CreateDataset("sampledataset")

cmd/internal/storage/redis/redis.go

@@ -101,11 +101,11 @@ func (s *redisStorage) AddStats(cInfo *info.ContainerInfo, stats *info.Container
 			s.lastWrite = time.Now()
 		}
 	}()
-	if len(seriesToFlush) > 0 {
-		// We use redis's "LPUSH" to push the data to the redis
-		s.conn.Send("LPUSH", s.redisKey, seriesToFlush)
+	if len(seriesToFlush) == 0 {
+		return nil
 	}
-	return nil
+	// We use redis's "LPUSH" to push the data to the redis
+	return s.conn.Send("LPUSH", s.redisKey, seriesToFlush)
 }
 
 func (s *redisStorage) Close() error {