fix pricing sync issue (#150)

* fix pricing sync with mutex on refresh

* expire cache items on load

Author: bwagner5

pkg/ec2pricing/odpricing.go

@@ -23,6 +23,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -44,6 +45,7 @@ type OnDemandPricing struct {
 	DirectoryPath  string
 	cache          *cache.Cache
 	pricingClient  pricingiface.PricingAPI
+	sync.RWMutex
 }
 
 func LoadODCacheOrNew(pricingClient pricingiface.PricingAPI, region string, fullRefreshTTL time.Duration, directoryPath string) *OnDemandPricing {
@@ -91,7 +93,9 @@ func loadODCacheFrom(itemTTL time.Duration, region string, expandedDirPath strin
 	if err := json.Unmarshal(cacheBytes, odCache); err != nil {
 		return nil, err
 	}
-	return cache.NewFrom(itemTTL, itemTTL, *odCache), nil
+	c := cache.NewFrom(itemTTL, itemTTL, *odCache)
+	c.DeleteExpired()
+	return c, nil
 }
 
 func getODCacheFilePath(region string, directoryPath string) string {
@@ -111,6 +115,8 @@ func odCacheRefreshJob(odPricing *OnDemandPricing) {
 }
 
 func (c *OnDemandPricing) Refresh() error {
+	c.Lock()
+	defer c.Unlock()
 	odInstanceTypeCosts, err := c.fetchOnDemandPricing("")
 	if err != nil {
 		return fmt.Errorf("there was a problem refreshing the on-demand instance type pricing cache: %v", err)
@@ -128,6 +134,8 @@ func (c *OnDemandPricing) Get(instanceType string) (float64, error) {
 	if cost, ok := c.cache.Get(instanceType); ok {
 		return cost.(float64), nil
 	}
+	c.RLock()
+	defer c.RUnlock()
 	costs, err := c.fetchOnDemandPricing(instanceType)
 	if err != nil {
 		return 0, fmt.Errorf("there was a problem fetching on-demand instance type pricing for %s: %v", instanceType, err)
@@ -154,6 +162,8 @@ func (c *OnDemandPricing) Save() error {
 }
 
 func (c *OnDemandPricing) Clear() error {
+	c.Lock()
+	defer c.Unlock()
 	c.cache.Flush()
 	return os.Remove(getODCacheFilePath(c.Region, c.DirectoryPath))
 }

pkg/ec2pricing/spotpricing.go

@@ -23,6 +23,7 @@ import (
 	"path/filepath"
 	"sort"
 	"strconv"
+	"sync"
 	"time"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -43,6 +44,7 @@ type SpotPricing struct {
 	DirectoryPath  string
 	cache          *cache.Cache
 	ec2Client      ec2iface.EC2API
+	sync.RWMutex
 }
 
 type spotPricingEntry struct {
@@ -98,7 +100,9 @@ func loadSpotCacheFrom(itemTTL time.Duration, region string, expandedDirPath str
 	if err := decoder.Decode(spotTimeSeries); err != nil {
 		return nil, err
 	}
-	return cache.NewFrom(itemTTL, itemTTL, *spotTimeSeries), nil
+	c := cache.NewFrom(itemTTL, itemTTL, *spotTimeSeries)
+	c.DeleteExpired()
+	return c, nil
 }
 
 func getSpotCacheFilePath(region string, directoryPath string) string {
@@ -118,6 +122,8 @@ func spotCacheRefreshJob(spotPricing *SpotPricing, days int) {
 }
 
 func (c *SpotPricing) Refresh(days int) error {
+	c.Lock()
+	defer c.Unlock()
 	spotInstanceTypeCosts, err := c.fetchSpotPricingTimeSeries("", days)
 	if err != nil {
 		return fmt.Errorf("there was a problem refreshing the spot instance type pricing cache: %v", err)
@@ -139,6 +145,8 @@ func (c *SpotPricing) Get(instanceType string, zone string, days int) (float64,
 		}
 	}
 	if !ok {
+		c.RLock()
+		defer c.RUnlock()
 		zonalSpotPricing, err := c.fetchSpotPricingTimeSeries(instanceType, days)
 		if err != nil {
 			return -1, fmt.Errorf("there was a problem fetching spot instance type pricing for %s: %v", instanceType, err)
@@ -224,6 +232,8 @@ func (c *SpotPricing) Save() error {
 }
 
 func (c *SpotPricing) Clear() error {
+	c.Lock()
+	defer c.Unlock()
 	c.cache.Flush()
 	return os.Remove(getSpotCacheFilePath(c.Region, c.DirectoryPath))
 }

pkg/selector/selector.go

@@ -261,7 +261,7 @@ func (itf Selector) prepareFilter(filters Filters, instanceTypeInfo instancetype
 	if itf.EC2Pricing.OnDemandCacheCount() > 0 {
 		price, err := itf.EC2Pricing.GetOnDemandInstanceTypeCost(instanceTypeName)
 		if err != nil {
-			log.Printf("Could not retrieve instantaneous hourly on-demand price for instance type %s\n", instanceTypeName)
+			log.Printf("Could not retrieve instantaneous hourly on-demand price for instance type %s - %s\n", instanceTypeName, err)
 		} else {
 			instanceTypeHourlyPriceOnDemand = &price
 			instanceTypeInfo.OndemandPricePerHour = instanceTypeHourlyPriceOnDemand