Merge pull request #283 from kubecost/bolt/lock-config-rw

Prevent Concurrent RW on Config

cloud/provider.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"reflect"
 	"strings"
+	"sync"
 
 	"k8s.io/klog"
 
@@ -33,6 +34,9 @@ var createTableStatements = []string{
 	);`,
 }
 
+// This Mutex is used to control read/writes to our default config file
+var configLock sync.Mutex
+
 // ReservedInstanceData keeps record of resources on a node should be
 // priced at reserved rates
 type ReservedInstanceData struct {
@@ -205,6 +209,9 @@ func CustomPricesEnabled(p Provider) bool {
 
 // GetDefaultPricingData will search for a json file representing pricing data in /models/ and use it for base pricing info.
 func GetDefaultPricingData(fname string) (*CustomPricing, error) {
+	configLock.Lock()
+	defer configLock.Unlock()
+
 	path := os.Getenv("CONFIG_PATH")
 	if path == "" {
 		path = "/models/"
@@ -264,6 +271,10 @@ func configmapUpdate(c *CustomPricing, path string, a map[string]string) (*Custo
 			return nil, err
 		}
 	}
+
+	configLock.Lock()
+	defer configLock.Unlock()
+
 	cj, err := json.Marshal(c)
 	if err != nil {
 		return nil, err