Merge pull request #25 from y-trudeau/DISTMYSQL-185

DISTMYSQL-185: Fix error management during relocation of replicas.

Author: kamil-holubicki

docker/Dockerfile.system

@@ -8,7 +8,7 @@ RUN echo "ci_env_repo: $ci_env_repo"
 RUN echo "ci_env_branch: $ci_env_branch"
 
 RUN apt-get update -q -y
-RUN apt-get install -y sudo haproxy python git jq rsync libaio1 libnuma1 default-mysql-client bsdmainutils less vim
+RUN apt-get install -y sudo haproxy python git jq rsync libaio1 libnuma1 default-mysql-client bsdmainutils less vim libncurses5
 
 RUN mkdir /orchestrator
 WORKDIR /orchestrator

go/inst/instance_topology.go

@@ -2814,6 +2814,7 @@ func relocateReplicasInternal(replicas [](*Instance), instance, other *Instance)
 		return RepointTo(replicas, &other.Key)
 	}
 	// GTID
+	gtidErrorsMsg := ""
 	{
 		movedReplicas, unmovedReplicas, err, errs := moveReplicasViaGTID(replicas, other, nil)
 
@@ -2824,6 +2825,18 @@ func relocateReplicasInternal(replicas [](*Instance), instance, other *Instance)
 			// something was moved via GTID; let's try further on
 			return relocateReplicasInternal(unmovedReplicas, instance, other)
 		}
+
+		// Making sure that if there are any errors in errs, they are reported
+		if len(errs) > 0 {
+			// There are errors, maybe more than one. Let's concatenate them
+			// so they can be reported correctly in the UI
+			gtidErrorsMsg = "Error(s): "
+
+			for _, err := range errs {
+				gtidErrorsMsg = fmt.Sprintf("%s; %v", gtidErrorsMsg, err)
+			}
+
+		}
 		// Otherwise nothing was moved via GTID. Maybe we don't have any GTIDs, we continue.
 	}
 
@@ -2847,7 +2860,11 @@ func relocateReplicasInternal(replicas [](*Instance), instance, other *Instance)
 	}
 
 	// Too complex
-	return nil, log.Errorf("Relocating %+v replicas of %+v below %+v turns to be too complex; please do it manually", len(replicas), instance.Key, other.Key), errs
+	// if the len of gtidErrorsMsg is less than 21, no errors were added
+	if len(gtidErrorsMsg) > 0 {
+		gtidErrorsMsg = "Additional Errors: " + gtidErrorsMsg
+	}
+	return nil, log.Errorf("Relocating %+v replicas of %+v below %+v turns to be too complex; please do it manually. %v", len(replicas), instance.Key, other.Key, gtidErrorsMsg), errs
 }
 
 // RelocateReplicas will attempt moving replicas of an instance indicated by instanceKey below another instance.