From 862ac54dc1370a289d6d647a3e7f66d2f236aa28 Mon Sep 17 00:00:00 2001
From: Waldemar Quevedo <wally@synadia.com>
Date: Fri, 15 Nov 2019 13:58:49 -0800
Subject: [PATCH] Add anti affinity for stan pods

Signed-off-by: Waldemar Quevedo <wally@synadia.com>
---
 nats-streaming-server/nats-streaming-auth.yml | 154 ++++++++++++++++++
 1 file changed, 154 insertions(+)
 create mode 100644 nats-streaming-server/nats-streaming-auth.yml

diff --git a/nats-streaming-server/nats-streaming-auth.yml b/nats-streaming-server/nats-streaming-auth.yml
new file mode 100644
index 00000000..272c3dd9
--- /dev/null
+++ b/nats-streaming-server/nats-streaming-auth.yml
@@ -0,0 +1,154 @@
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: stan-config
+data:
+  stan.conf: |
+    port: 4222
+    http: 8222
+
+    leafnodes {
+      remotes = [
+        {
+            url: "nats://nats:7422"
+            credentials: "/var/run/nats/secrets/stan.creds"
+        }
+      ]
+    }
+
+    streaming {
+     id: stan
+     store: file
+     dir: /data/stan/store
+
+     cluster {
+       node_id: $POD_NAME
+
+       log_path: /data/stan/log
+
+       # Explicit names of resulting peers
+       peers: ["stan-0", "stan-1", "stan-2"]
+      }
+    }
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: stan
+  labels:
+    app: stan
+spec:
+  selector:
+    app: stan
+  clusterIP: None
+  ports:
+  - name: metrics
+    port: 7777
+---
+apiVersion: apps/v1
+kind: StatefulSet
+metadata:
+  name: stan
+  labels:
+    app: stan
+spec:
+  selector:
+    matchLabels:
+      app: stan
+  serviceName: stan
+  replicas: 3
+  volumeClaimTemplates:
+  - metadata:
+      name: stan-sts-vol
+    spec:
+      accessModes:
+      - ReadWriteOnce
+      volumeMode: "Filesystem"
+      resources:
+        requests:
+          storage: 1Gi
+  template:
+    metadata:
+      labels:
+        app: stan
+    spec:
+      # Prevent NATS Streaming pods running in same host.
+      affinity:
+        podAntiAffinity:
+          requiredDuringSchedulingIgnoredDuringExecution:
+          - topologyKey: "kubernetes.io/hostname"
+            labelSelector:
+              matchExpressions:
+              - key: app
+                operator: In
+                values:
+                - stan
+      # STAN Server
+      containers:
+      - name: stan
+        image: nats-streaming:0.16.2
+        ports:
+        - containerPort: 8222
+          name: monitor
+        - containerPort: 7777
+          name: metrics
+        args:
+         - "-sc"
+         - "/etc/stan-config/stan.conf"
+
+        # Required to be able to define an environment variable
+        # that refers to other environment variables.  This env var
+        # is later used as part of the configuration file.
+        env:
+        - name: POD_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.name
+        - name: POD_NAMESPACE
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.namespace
+        volumeMounts:
+          - name: config-volume
+            mountPath: /etc/stan-config
+          - name: creds-volume
+            mountPath: /var/run/nats/secrets
+          - name: stan-sts-vol
+            mountPath: /data/stan
+
+        # Disable CPU limits.
+        resources:
+          requests:
+            cpu: 0
+
+        livenessProbe:
+          httpGet:
+            path: /
+            port: 8222
+          initialDelaySeconds: 10
+          timeoutSeconds: 5
+      - name: metrics
+        image: synadia/prometheus-nats-exporter:0.6.0
+        args:
+        - -connz
+        - -routez
+        - -subz
+        - -varz
+        - -channelz
+        - -serverz
+        # - -prefix=stan
+        - -use_internal_server_id
+        - -DV
+        - http://localhost:8222/
+        ports:
+        - containerPort: 7777
+          name: metrics
+      volumes:
+      - name: config-volume
+        configMap:
+          name: stan-config
+      - name: creds-volume
+        secret:
+          secretName: stan-creds