Allow configuration of dynamodb storage to specify the max retries of aws sdk (#4115)

physical/dynamodb/dynamodb.go

@@ -183,6 +183,19 @@ func NewDynamoDBBackend(conf map[string]string, logger log.Logger) (physical.Bac
 		}
 	}
 
+	dynamodbMaxRetryString := os.Getenv("AWS_DYNAMODB_MAX_RETRIES")
+	if dynamodbMaxRetryString == "" {
+		dynamodbMaxRetryString = conf["dynamodb_max_retries"]
+	}
+	var dynamodbMaxRetry int = aws.UseServiceDefaultRetries
+	if dynamodbMaxRetryString != "" {
+		var err error
+		dynamodbMaxRetry, err = strconv.Atoi(dynamodbMaxRetryString)
+		if err != nil {
+			return nil, fmt.Errorf("invalid max retry: %s", dynamodbMaxRetryString)
+		}
+	}
+
 	credsConfig := &awsutil.CredentialsConfig{
 		AccessKey:    accessKey,
 		SecretKey:    secretKey,
@@ -202,7 +215,8 @@ func NewDynamoDBBackend(conf map[string]string, logger log.Logger) (physical.Bac
 		WithEndpoint(endpoint).
 		WithHTTPClient(&http.Client{
 			Transport: pooledTransport,
-		})
+		}).
+		WithMaxRetries(dynamodbMaxRetry)
 	client := dynamodb.New(session.New(awsConf))
 
 	if err := ensureTableExists(client, table, readCapacity, writeCapacity); err != nil {