Add single node examples

Signed-off-by: Waldemar Quevedo <[email protected]>
cf250024 · Jan 21, 2020 · dceee19 · dceee19
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diff --git a/docs/simple-setup.md b/docs/simple-setup.md
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+# Basic NATS and NATS Streaming setup in K8S
+
+## Minimal NATS and NATS Streaming setup
+
+To try NATS with the minimal components, you can start with the following:
+
+```sh
+# Single server NATS
+kubectl apply -f https://raw.githubusercontent.com/nats-io/k8s/master/nats-server/single-server-nats.yml
+
+kubectl apply -f https://raw.githubusercontent.com/nats-io/k8s/master/nats-streaming-server/single-server-stan.yml
+```
+
+This will setup for you:
+
+- A statefulset with a single NATS server (no auth nor TLS)
+
+- A single NATS Streaming node using file store with persistence
+
+- A `nats` headless service to which you can connect.
+
+- A NATS Streaming Server that uses the cluster name `stan`.
+
+Note that the only service that your applications have to connect is
+the `nats` service, the NATS Streaming server will be available by
+using NATS as a transport.
+
+Next, try using `nats-box` to connect to the `nats` service to confirm
+that you have set both NATS and NATS Streaming correctly.
+
+```sh
+kubectl run -i --rm --tty nats-box --image=synadia/nats-box --restart=Never
+
+# Send message to NATS
+nats-box:~# nats-sub -s nats hello &
+Listening on [hello]
+
+nats-box:~# nats-pub -s nats hello world
+[#1] Received on [hello]: 'world'
+
+# Send/Receive message to STAN
+nats-box:~# stan-pub -s nats -c stan hello world
+Published [hello] : 'world'
+
+nats-box:~# stan-sub -s nats -c stan hello
+Connected to nats clusterID: [stan] clientID: [stan-sub]
+Listening on [hello], clientID=[stan-sub], qgroup=[] durable=[]
+[#1] Received: sequence:1 subject:"hello" data:"world" timestamp:1579544643374163630 
+```
+
+## HA setup using StatefulSets
+
+In order to have higher availability you can setup NATS and NATS
+Streaming (STAN) to run in clustering mode.  The following commands
+will setup a 3-node NATS cluster as well as a 3-node NATS Streaming
+cluster that has an attached volume for persistence.
+
+```sh
+# Create NATS cluster
+kubectl apply -f https://raw.githubusercontent.com/nats-io/k8s/master/nats-server/simple-nats.yml
+
+# Create STAN cluster
+kubectl apply -f https://raw.githubusercontent.com/nats-io/k8s/master/nats-streaming-server/simple-stan.yml
+```
+
+For NATS Streaming, it is actually recommended to use the Fault
+Tolerance mode as that would show better performance than clustering
+mode and better failover.  You can follow this guide to setup
+[NATS Streaming with Fault Tolerance](https://docs.nats.io/nats-on-kubernetes/stan-ft-k8s-aws).
diff --git a/nats-server/single-server-nats.yml b/nats-server/single-server-nats.yml
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+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: nats-config
+data:
+  nats.conf: |
+    pid_file: "/var/run/nats/nats.pid"
+    http: 8222
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: nats
+  labels:
+    app: nats
+spec:
+  selector:
+    app: nats
+  clusterIP: None
+  ports:
+  - name: client
+    port: 4222
+  - name: cluster
+    port: 6222
+  - name: monitor
+    port: 8222
+  - name: metrics
+    port: 7777
+  - name: leafnodes
+    port: 7422
+  - name: gateways
+    port: 7522
+---
+apiVersion: apps/v1
+kind: StatefulSet
+metadata:
+  name: nats
+  labels:
+    app: nats
+spec:
+  selector:
+    matchLabels:
+      app: nats
+  replicas: 1
+  serviceName: "nats"
+  template:
+    metadata:
+      labels:
+        app: nats
+    spec:
+      # Common volumes for the containers
+      volumes:
+      - name: config-volume
+        configMap:
+          name: nats-config
+      - name: pid
+        emptyDir: {}
+
+      # Required to be able to HUP signal and apply config reload
+      # to the server without restarting the pod.
+      shareProcessNamespace: true
+
+      #################
+      #               #
+      #  NATS Server  #
+      #               #
+      #################
+      terminationGracePeriodSeconds: 60
+      containers:
+      - name: nats
+        image: nats:2.1.0-alpine3.10
+        ports:
+        - containerPort: 4222
+          name: client
+          hostPort: 4222
+        - containerPort: 7422
+          name: leafnodes
+          hostPort: 7422
+        - containerPort: 6222
+          name: cluster
+        - containerPort: 8222
+          name: monitor
+        - containerPort: 7777
+          name: metrics
+        command:
+         - "nats-server"
+         - "--config"
+         - "/etc/nats-config/nats.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
+        - name: CLUSTER_ADVERTISE
+          value: $(POD_NAME).nats.$(POD_NAMESPACE).svc
+        volumeMounts:
+          - name: config-volume
+            mountPath: /etc/nats-config
+          - name: pid
+            mountPath: /var/run/nats
+
+        # Liveness/Readiness probes against the monitoring
+        #
+        livenessProbe:
+          httpGet:
+            path: /
+            port: 8222
+          initialDelaySeconds: 10
+          timeoutSeconds: 5
+        readinessProbe:
+          httpGet:
+            path: /
+            port: 8222
+          initialDelaySeconds: 10
+          timeoutSeconds: 5
+
+        # Gracefully stop NATS Server on pod deletion or image upgrade.
+        #
+        lifecycle:
+          preStop:
+            exec:
+              # Using the alpine based NATS image, we add an extra sleep that is
+              # the same amount as the terminationGracePeriodSeconds to allow
+              # the NATS Server to gracefully terminate the client connections.
+              #
+              command: ["/bin/sh", "-c", "/nats-server -sl=ldm=/var/run/nats/nats.pid && /bin/sleep 60"]
diff --git a/nats-streaming-server/single-server-stan.yml b/nats-streaming-server/single-server-stan.yml
@@ -0,0 +1,115 @@
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: stan-config
+data:
+  stan.conf: |
+    port: 4222
+    http: 8222
+
+    streaming {
+     ns: "nats://nats:4222"
+     id: stan
+     store: file
+     dir: /data/stan/store
+    }
+---
+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: 1
+  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: stan-sts-vol
+            mountPath: /data/stan
+
+        # Disable CPU limits.
+        resources:
+          requests:
+            cpu: 0
+
+        livenessProbe:
+          httpGet:
+            path: /
+            port: 8222
+          initialDelaySeconds: 10
+          timeoutSeconds: 5
+      volumes:
+      - name: config-volume
+        configMap:
+          name: stan-config