MLE-14200 Use useLegacyHostnames to fix upgrade backward compatibility issue (#235)

* MLE-14181 Upgrade Bug with group config is set

* MLE-14200 Persist the Name Change after Upgrade

* update comments about useLegacyHostnames

---------

Co-authored-by: Peng Zhou <[email protected]>

Author: pengzhouml

README.md

@@ -107,7 +107,8 @@ Following table lists all the parameters supported by the latest MarkLogic Helm
 | `updateStrategy.type`                               | Update strategy for MarkLogic pods                                                                                                                                                     | `OnDelete`                 |
 | `terminationGracePeriod`                            | Seconds the MarkLogic Pod terminate gracefully                                                                                                                                         | `120`                      |
 | `clusterDomain`                                     | Domain for the Kubernetes cluster                                                                                                                                                      | `cluster.local`            |
-| `allowLongHostnames`                                | Allow deployment with hostname over 64 characters                                                    | `false` |∂
+| `allowLongHostnames`                                | Allow deployment with hostname over 64 characters                                                    | `false` |
+| `useLegacyHostnames`                                | Use the lagecy hostnames that is used before 1.1.0 version.                                          | `false` |
 | `group.name`                                        | Group name for joining MarkLogic cluster                                                                                                                                               | `Default`                  |
 | `group.enableXdqpSsl`                               | SSL encryption for XDQP                                                                                                                                                                | `true`                     |
 | `bootstrapHostName`                                 | Host name of MarkLogic bootstrap host (to join a cluster)                                                                                                                              | `""`                       |

charts/templates/_helpers.tpl

@@ -37,26 +37,38 @@ oldFullname is the name used before 1.1.x release
 {{- if .Release.IsInstall -}}
 {{- true }}
 {{- else }}
-{{- if .Values.fullnameOverride  -}}
-{{- $overridenName := trim .Values.fullnameOverride -}}
-{{- $labels := (lookup "apps/v1" "StatefulSet" .Release.Namespace $overridenName).metadata.labels  -}}
-{{- $chartVersionFull := get $labels "helm.sh/chart" -}}
-{{- $chartVersionString := trimPrefix "marklogic-" $chartVersionFull -}}
-{{- $chartVersionString := $chartVersionString | replace "." "" -}}
-{{- $chartVersionDigit := int $chartVersionString}}
-{{- if lt $chartVersionDigit 110  -}}
+{{- if eq .Values.useLegacyHostnames true -}}
 {{- false }}
 {{- else }}
 {{- true }}
 {{- end }}
-{{- else }}
-{{- $newCm := (lookup "apps/v1" "StatefulSet" .Release.Namespace (include "marklogic.newFullname" .)) }}
-{{- if $newCm  }}
-{{- true }}
-{{- else }}
-{{- false }}
 {{- end }}
 {{- end }}
+
+{{- define "marklogic.checkUpgradeError" -}}
+{{- if and .Release.IsUpgrade (ne .Values.useLegacyHostnames true) -}}
+{{- $stsName := trim (include "marklogic.oldFullname" .) -}}
+{{- if .Values.fullnameOverride  -}}
+{{- $stsName := trim .Values.fullnameOverride -}}
+{{- end }}
+{{- $sts := lookup "apps/v1" "StatefulSet" .Release.Namespace $stsName }}
+{{- if $sts }}
+{{- $labels := $sts.metadata.labels }}
+{{- $chartVersionFull := get $labels "helm.sh/chart" }}
+{{- if $chartVersionFull }}
+{{- $chartVersionWithDot := trimPrefix "marklogic-" $chartVersionFull }}
+{{- $chartVersionString := $chartVersionWithDot | replace "." "" }}
+{{- $chartVersionDigit := int $chartVersionString }}
+{{- if lt $chartVersionDigit 110 -}}
+{{- $errorMessage := printf "New hostnames has been introduced since version 1.1.0. You are upgrading from version %s to version %s. To make the upgrade successful, please set the following configuration in values file to keep using the legacy hostname: \n\nuseLegacyHostnames: true\n" $chartVersionWithDot .Chart.Version }}
+{{- fail $errorMessage }}
+{{- end }}
+{{- end }}
+{{- end }}
+{{- end }}
+{{- end }}
+
+{{/*
 {{- end }}
 {{- end }}
 

charts/templates/statefulset.yaml

@@ -1,3 +1,4 @@
+{{- include "marklogic.checkUpgradeError" . -}}
 {{- include "marklogic.checkInputError" . }}
 apiVersion: apps/v1
 kind: StatefulSet

charts/values.yaml

@@ -21,6 +21,11 @@ clusterDomain: cluster.local
 ## There is a limit of 64 characters for CN in the certificate
 allowLongHostnames: false
 
+## This flag facilitates upgrading from version 1.0.x of the chart while retaining the use of legacy hostnames. 
+## When upgrading from version 1.0.x to any version above 1.1.0, this flag must be set to true.
+## It should remain true for all future upgrades. For new installations, this flag should be set to false.
+useLegacyHostnames: false
+
 ## Group related settings
 group:
   ## the group name of the current Marklogic Helm Deployment