Retry 502 errors one time

go.mod

@@ -12,7 +12,7 @@ require (
 	github.com/jen20/awspolicyequivalence v1.1.0
 	github.com/jinzhu/copier v0.2.3
 	github.com/mitchellh/go-homedir v1.1.0
-	github.com/opentelekomcloud/gophertelekomcloud v0.2.7-0.20210317130019-8526a9584142
+	github.com/opentelekomcloud/gophertelekomcloud v0.2.7-0.20210319160506-316fc19ae099
 	github.com/unknwon/com v1.0.1
 	gopkg.in/yaml.v2 v2.4.0
 )

go.sum

@@ -276,8 +276,8 @@ github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e h1:fD57ERR4JtEqsWb
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
 github.com/oklog/run v1.0.0 h1:Ru7dDtJNOyC66gQ5dQmaCa0qIsAUFY3sFpK1Xk8igrw=
 github.com/oklog/run v1.0.0/go.mod h1:dlhp/R75TPv97u0XWUtDeV/lRKWPKSdTuV0TZvrmrQA=
-github.com/opentelekomcloud/gophertelekomcloud v0.2.7-0.20210317130019-8526a9584142 h1:Z3GXIhdiWk0PQdxF9w2bARJWCX4rUAitymnX2NziX14=
-github.com/opentelekomcloud/gophertelekomcloud v0.2.7-0.20210317130019-8526a9584142/go.mod h1:pzEP1kduNwv+hrI9R6/DFU/NiX7Kr9NiFjpQ7kJQTsM=
+github.com/opentelekomcloud/gophertelekomcloud v0.2.7-0.20210319160506-316fc19ae099 h1:jAp6XZZVRoMQ9FER9SuLpgLUOPwRGO+HPW+E6TpZDyk=
+github.com/opentelekomcloud/gophertelekomcloud v0.2.7-0.20210319160506-316fc19ae099/go.mod h1:pzEP1kduNwv+hrI9R6/DFU/NiX7Kr9NiFjpQ7kJQTsM=
 github.com/pierrec/lz4 v2.0.5+incompatible/go.mod h1:pdkljMzZIN41W+lC3N2tnIh5sFi+IEE17M5jbnwPHcY=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=

opentelekomcloud/common/cfg/transport_test.go

@@ -0,0 +1,84 @@
+package cfg
+
+import (
+	"fmt"
+	"net/http"
+	"sync"
+	"testing"
+
+	golangsdk "github.com/opentelekomcloud/gophertelekomcloud"
+	th "github.com/opentelekomcloud/gophertelekomcloud/testhelper"
+)
+
+type failHandler struct {
+	ExpectedFailures int
+	ErrorCode        int
+	FailCount        int
+	OkCode           int
+	OkResponse       string
+
+	mut *sync.RWMutex
+}
+
+func (f *failHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if f.mut == nil {
+		f.mut = new(sync.RWMutex)
+	}
+
+	if f.OkCode == 0 {
+		f.OkCode = 200
+	}
+
+	defer func() { _ = r.Body.Close() }()
+	if f.FailCount < f.ExpectedFailures {
+		f.mut.Lock()
+		f.FailCount += 1
+		f.mut.Unlock()
+		w.WriteHeader(f.ErrorCode)
+	} else {
+		w.WriteHeader(f.OkCode)
+		_, _ = fmt.Fprintf(w, f.OkResponse)
+	}
+}
+
+const tokenOutput = `
+{
+   "token":{
+      "methods":[
+         "password"
+      ],
+      "roles":[],
+      "expires_at":"2017-06-03T02:19:49.000000Z",
+      "project":{},
+      "catalog":[],
+      "user": {},
+      "issued_at":"2017-06-03T01:19:49.000000Z"
+   }
+}
+`
+
+func TestRoundTripperRetry(t *testing.T) {
+	th.SetupHTTP()
+	defer th.TeardownHTTP()
+
+	failHandler := &failHandler{
+		ExpectedFailures: 1,
+		ErrorCode:        502,
+		OkCode:           201,
+		OkResponse:       tokenOutput,
+	}
+
+	th.Mux.Handle("/", failHandler)
+
+	cfg := &Config{MaxRetries: failHandler.ExpectedFailures}
+
+	_, err := cfg.genClient(golangsdk.AuthOptions{
+		IdentityEndpoint: th.Endpoint() + "v3",
+		Username:         "user",
+		Password:         "qwerty!",
+		DomainName:       "DOMAIN001",
+	})
+
+	th.CheckNoErr(t, err)
+	th.AssertEquals(t, failHandler.ExpectedFailures, failHandler.FailCount)
+}