use exponential back off func from realis lib

retry.go

@@ -19,14 +19,26 @@ limitations under the License.
 package realis
 
 import (
-	"time"
 	"errors"
+	"strings"
+	"time"
+
+	"github.com/paypal/gorealis/gen-go/apache/aurora"
 )
 
+const (
+	ConnRefusedErr   = "connection refused"
+	NoLeaderFoundErr = "No leader found"
+)
+
+var RetryConnErr = errors.New("error occured during with aurora retrying")
+
 // ConditionFunc returns true if the condition is satisfied, or an error
 // if the loop should be aborted.
 type ConditionFunc func() (done bool, err error)
 
+type AuroraFunc func() (resp *aurora.Response, err error)
+
 // ExponentialBackoff repeats a condition check with exponential backoff.
 //
 // It checks the condition up to Steps times, increasing the wait by multiplying
@@ -54,3 +66,21 @@ func ExponentialBackoff(backoff Backoff, condition ConditionFunc) error {
 	}
 	return errors.New("Timed out while retrying")
 }
+
+// CheckAndRetryConn function takes realis client and a trhift API function to call and returns response and error
+// If Error from the APi call is Retry able . THe functions re establishes the connection with aurora by getting the latest aurora master from zookeeper.
+// If Error is retyable return resp and RetryConnErr error.
+func CheckAndRetryConn(r Realis, aurorajob AuroraFunc) (*aurora.Response, error) {
+	resp, cliErr := aurorajob()
+	if strings.Contains(cliErr.Error(), ConnRefusedErr) || strings.Contains(cliErr.Error(), NoLeaderFoundErr) {
+		conErr := r.ReestablishConn()
+		if conErr != nil {
+			return resp, RetryConnErr
+		}
+		return resp, RetryConnErr
+	}
+	if resp != nil && resp.GetResponseCode() != aurora.ResponseCode_ERROR_TRANSIENT {
+		return resp, RetryConnErr
+	}
+	return resp, cliErr
+}