Fixes hystrix timeout (#58)

* Fixes hystrix timeout

- Fixes issue where hystrix timeout was being set in nanosecond instead
of millisecond

* Adds test for duration to Int conversion

- Improves implementation of durtationToInt
- Adds test

* Update golint import

Makefile

@@ -6,7 +6,7 @@ ALL_PACKAGES=$(shell go list ./... | grep -v "vendor")
 setup:
 	mkdir -p $(GOPATH)/bin
 	go get -u github.com/golang/dep/cmd/dep
-	go get -u github.com/golang/lint/golint
+	go get -u golang.org/x/lint/golint
 
 build-deps:
 	dep ensure

hystrix/hystrix_client.go

@@ -38,6 +38,9 @@ const (
 	defaultErrorPercentThreshold  = 25
 	defaultSleepWindow            = 10
 	defaultRequestVolumeThreshold = 10
+
+	maxUint = ^uint(0)
+	maxInt  = int(maxUint >> 1)
 )
 
 var _ heimdall.Client = (*Client)(nil)
@@ -67,7 +70,7 @@ func NewClient(opts ...Option) *Client {
 	}
 
 	hystrix.ConfigureCommand(client.hystrixCommandName, hystrix.CommandConfig{
-		Timeout:                int(client.hystrixTimeout),
+		Timeout:                durationToInt(client.hystrixTimeout, time.Millisecond),
 		MaxConcurrentRequests:  client.maxConcurrentRequests,
 		RequestVolumeThreshold: client.requestVolumeThreshold,
 		SleepWindow:            client.sleepWindow,
@@ -77,6 +80,18 @@ func NewClient(opts ...Option) *Client {
 	return &client
 }
 
+func durationToInt(duration, unit time.Duration) int {
+	durationAsNumber := duration / unit
+
+	if int64(durationAsNumber) > int64(maxInt) {
+		// Returning max possible value seems like best possible solution here
+		// the alternative is to panic as there is no way of returning an error
+		// without changing the NewClient API
+		return maxInt
+	}
+	return int(durationAsNumber)
+}
+
 // Get makes a HTTP GET request to provided URL
 func (hhc *Client) Get(url string, headers http.Header) (*http.Response, error) {
 	var response *http.Response

hystrix/hystrix_client_test.go

@@ -530,3 +530,19 @@ func respBody(t *testing.T, response *http.Response) string {
 
 	return string(respBody)
 }
+
+func TestDurationToInt(t *testing.T) {
+	t.Run("1sec should return 1 when unit is second", func(t *testing.T) {
+		timeout := 1 * time.Second
+		timeoutInSec := durationToInt(timeout, time.Second)
+
+		assert.Equal(t, 1, timeoutInSec)
+	})
+
+	t.Run("30sec should return 30000 when unit is millisecond", func(t *testing.T) {
+		timeout := 30 * time.Second
+		timeoutInMs := durationToInt(timeout, time.Millisecond)
+
+		assert.Equal(t, 30000, timeoutInMs)
+	})
+}