Opt to enable linkerd proxy shutdown from lifecycle preStop

Added a new `linkerd` object to values & schema. If `enabled=true` & `shutdownAfterCheckpoint=true`, then the STS pod's `lifecycle.preStop` hook will be configured to issue a shutdown call to the local linkerd-proxy. This is entirely optional. If a deployment is not using linkerd, then this option should be left in the default disabled state.
timescale · Dec 6, 2023 · 8073965 · 8073965
1 parent 7ded6b6
commit 8073965
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Showing 6 changed files with 39 additions and 1 deletion.
diff --git a/charts/timescaledb-single/scripts/prestop.sql b/charts/timescaledb-single/scripts/prestop.sql
@@ -60,3 +60,7 @@ CHECKPOINT;
     SELECT 'We are a primary: Successfully invoked checkpoints, now issuing a switchover.';
     \! curl -s http://localhost:8008/switchover -XPOST -d '{"leader": "$(hostname)"}'
 \endif
+
+\if :linkerdShutdown
+    \! curl -s -m 5 -X POST http://localhost:4191/shutdown
+\endif
diff --git a/charts/timescaledb-single/templates/configmap-scripts.yaml b/charts/timescaledb-single/templates/configmap-scripts.yaml
@@ -33,4 +33,3 @@ data:
     {{- .Files.Get "scripts/patroni_callback.sh" | nindent 4 }}
   lifecycle_preStop.sql: |-
     {{- .Files.Get "scripts/prestop.sql" | nindent 4 }}
-...
diff --git a/charts/timescaledb-single/templates/statefulset-timescaledb.yaml b/charts/timescaledb-single/templates/statefulset-timescaledb.yaml
@@ -113,6 +113,7 @@ spec:
               command:
               - psql
               - -X
+              - --set=linkerdShutdown="{{ if and .Values.linkerd.enabled .Values.linkerd.terminateAfterCheckpoint }}1{{else}}0{{end}}"
               - --file
               - "{{ template "scripts_dir" . }}/lifecycle_preStop.sql"
         # When reusing an already existing volume it sometimes happens that the permissions

diff --git a/charts/timescaledb-single/values.schema.json b/charts/timescaledb-single/values.schema.json
@@ -226,6 +226,22 @@
       },
       "type": "object"
     },
+    "linkerd": {
+      "additionalProperties": false,
+      "properties": {
+        "enabled": {
+          "type": [
+            "boolean"
+          ]
+        },
+        "terminateAfterCheckpoint": {
+          "type": [
+            "boolean"
+          ]
+        }
+      },
+      "type": "object"
+    },
     "enabled": {
       "additionalProperties": true
     },
@@ -818,6 +834,7 @@
     "fullnameOverride",
     "image",
     "curlImage",
+    "linkerd",
     "networkPolicy",
     "nodeSelector",
     "patroni",

diff --git a/charts/timescaledb-single/values.schema.yaml b/charts/timescaledb-single/values.schema.yaml
@@ -18,6 +18,7 @@ required:
   - fullnameOverride
   - image
   - curlImage
+  - linkerd
   - networkPolicy
   - nodeSelector
   - patroni
@@ -432,6 +433,14 @@ properties:
         type:
           - string
           - "null"
+  linkerd:
+    type: object
+    additionalProperties: false
+    properties:
+      enabled:
+        type: boolean
+      terminateAfterCheckpoint:
+        type: boolean
   env:
     type:
       - array

diff --git a/charts/timescaledb-single/values.yaml b/charts/timescaledb-single/values.yaml
@@ -597,3 +597,11 @@ debug:
   # This command will be executed *before* the main container starts. In the
   # example below, we can mimick a slow restore by sleeping for 5 minutes before starting
   execStartPre:  # sleep 300
+
+# Support for specific use cases when deploying with the linkerd service mesh.
+linkerd:
+  enabled: false
+  # As part of the statefulset pod's `lifecycle.preStop`, call the local linkerd sidecar
+  # to cleanly terminate the proxy. If this is not performed, then the proxy will remain
+  # alive unnecessarily, blocking pod termination for a period of time.
+  terminateAfterCheckpoint: true