01-redis-failover.yaml

apiVersion: v1
kind: Secret
metadata:
  name: om-secret
type: Opaque
data:
  # WARNING 
  # Redis-operator doesn't support the authentication yet: 
  # https://github.com/spotahome/redis-operator/issues/66
  # 
  # So for Open Match components to work these keys must always be empty.
  redis.user: |
  redis.password: |
---
apiVersion: storage.spotahome.com/v1alpha2
kind: RedisFailover
metadata:
  name: redisfailover
  labels:
    tier: storage
spec:
  hardAntiAffinity: true                     # Optional. Value by default. If true, the pods will not be scheduled on the same node.
  sentinel:
    replicas: 3                              # Optional. 3 by default, can be set higher.
    resources:                               # Optional. If not set, it won't be defined on created resources.
      requests:
        cpu: 100m
      limits:
        memory: 100Mi
    customConfig: []                         # Optional. Empty by default.
  redis:
    replicas: 3                              # Optional. 3 by default, can be set higher.
    image: redis                             # Optional. "redis" by default.
    version: 4.0.11-alpine                   # Optional. "3.2-alpine" by default.
    resources:                               # Optional. If not set, it won't be defined on created resources
      requests:
        cpu: 100m
        memory: 100Mi
      limits:
        cpu: 400m
        memory: 500Mi
    exporter: false                          # Optional. False by default. Adds a redis-exporter container to export metrics.
    exporterImage: oliver006/redis_exporter  # Optional. oliver006/redis_exporter by default.
    exporterVersion: v0.11.3                 # Optional. v0.11.3 by default.
    disableExporterProbes: false             # Optional. False by default. Disables the readiness and liveness probes for the exporter.
    storage:
      emptyDir: {}                           # Optional. emptyDir by default.
    customConfig: []                         # Optional. Empty by default.\
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: redis-master-proxy-configmap
data:
  haproxy.cfg: |
    defaults REDIS
      mode tcp
      timeout connect 5s
      timeout client 61s # should respect 'redis.pool.idleTimeout' from open-match config
      timeout server 61s
    global
      stats socket ipv4@127.0.0.1:9999 level admin
      stats timeout 2m
    frontend fe_redis
      bind *:17000 name redis
      default_backend be_redis
    backend be_redis
      server redis-master-serv 127.0.0.1:6379

  redis-master-finder.sh: |
    #!/bin/sh
    set -e
    set -u
 
    SENTINEL_HOST="rfs-redisfailover" # change this if RedisFailover name changes

    LAST_MASTER_IP=""
    LAST_MASTER_PORT=""

    update_master_addr() {
        # lookup current master address
        local r="SENTINEL get-master-addr-by-name mymaster"
        local r_out=$(echo $r | nc -q1 $SENTINEL_HOST 26379)

        # parse output
        local master_ip=$(echo "${r_out}" | tail -n+3 | head -n1 | tr -d '\r') # IP is on 3d line
        local master_port=$(echo "${r_out}" | tail -n+5 | head -n1 | tr -d '\r') # 5th line is port number

        # update HAProxy cfg if needed
        if [ "$master_ip" != "$LAST_MASTER_IP" ] || [ "$master_port" != "$LAST_MASTER_PORT" ]; then
            local s="set server be_redis/redis-master-serv addr ${master_ip} port ${master_port}"
            echo $s | nc 127.0.0.1 9999 # haproxy is in the same pod
            
            LAST_MASTER_IP=$master_ip
            LAST_MASTER_PORT=$master_port
            echo "New master address is ${LAST_MASTER_IP}:${LAST_MASTER_PORT}"
        fi
    }

    while :; do update_master_addr; sleep 1; done
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: redis-master-proxy
  labels:
    app: openmatch
    component: redis
    tier: storage
spec:
  replicas: 1
  selector:
    matchLabels:
      app: openmatch
      component: redis
      tier: storage
  template:
    metadata:
      labels:
        app: openmatch
        component: redis
        tier: storage
    spec:
      volumes:
      - name: configmap
        configMap:
          name: redis-master-proxy-configmap
          defaultMode: 0700
      containers:
      - name: redis-master-haproxy
        image: haproxy:1.8-alpine
        ports:
        - name: haproxy
          containerPort: 17000
        - name: haproxy-stats
          containerPort: 9999
        volumeMounts:
        - name: configmap
          mountPath: /usr/local/etc/haproxy/haproxy.cfg
          subPath: haproxy.cfg
      - name: redis-master-finder
        image: subfuzion/netcat # alpine image with only netcat-openbsd installed
        imagePullPolicy: Always
        command: ["redis-master-finder.sh"]
        volumeMounts:
        - name: configmap
          mountPath: /usr/local/bin/redis-master-finder.sh
          subPath: redis-master-finder.sh
        resources:
          requests:
            memory: 20Mi
            cpu: 100m
---
kind: Service
apiVersion: v1
metadata:
  name: redis
spec:
  selector:
    app: openmatch
    component: redis
    tier: storage
  ports:
  - protocol: TCP
    port: 6379
    targetPort: haproxy