Kube (brentley#3)

* changing az labels

* fix startup

* updating to read from env

* updating entrypoint

* entrypoint bash

Author: brentley

Dockerfile

@@ -10,7 +10,7 @@ ENV NODE_ENV ${NODE}
 # copy package info early to install npms and delete npm command
 WORKDIR /usr/src/app
 COPY package*.json ./
-RUN apk -U add curl nodejs nodejs-npm && \
+RUN apk -U add curl jq bash nodejs nodejs-npm && \
   npm install && apk del --purge nodejs-npm && \
   rm -rvf /var/cache/* /root/.npm /tmp/*
 
@@ -19,4 +19,4 @@ COPY . .
 HEALTHCHECK --interval=10s --timeout=3s \
   CMD curl -f -s http://localhost:3000/health/ || exit 1
 EXPOSE 3000
-CMD [ "node", "server.js" ]
+ENTRYPOINT ["bash","/usr/src/app/startup.sh"]

kubernetes/deployment.yaml

@@ -0,0 +1,29 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: ecsdemo-nodejs
+  labels:
+    app: ecsdemo-nodejs
+  namespace: default
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: ecsdemo-nodejs
+  strategy:
+    rollingUpdate:
+      maxSurge: 25%
+      maxUnavailable: 25%
+    type: RollingUpdate
+  template:
+    metadata:
+      labels:
+        app: ecsdemo-nodejs
+    spec:
+      containers:
+      - image: brentley/ecsdemo-nodejs:latest
+        imagePullPolicy: Always
+        name: ecsdemo-nodejs
+        ports:
+        - containerPort: 3000
+          protocol: TCP

kubernetes/service.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: ecsdemo-nodejs
+spec:
+  selector:
+    app: ecsdemo-nodejs
+  ports:
+   -  protocol: TCP
+      port: 80
+      targetPort: 3000
+

server.js

@@ -5,24 +5,12 @@ var app = express();
 var fs = require('fs');
 var code_hash = fs.readFileSync('code_hash.txt','utf8');
 console.log (code_hash);
+console.log('The IPADDRESS is:', process.env.IP);
+console.log('The message is:', process.env.AZ);
+console.log('The hash is: %s', code_hash);
 
-// internal-ip: detect the correct IP based on default gw
-var internalip = require('internal-ip');
-var ipaddress = internalip.v4.sync();
-
-// use ipaddress to find interface netmask
-var ifaces = require('os').networkInterfaces();
-for (var dev in ifaces) {
-  // ... and find the one that matches the criteria
-  var iface = ifaces[dev].filter(function(details) {
-    return details.address === `${ipaddress}` && details.family === 'IPv4';
-  });
-  if(iface.length > 0) ifacenetmask = iface[0].netmask;
-}
-
-// ip: separate out the network using the subnet mask
-var ipnet = require('ip');
-var network = ipnet.mask(`${ipaddress}`, `${ifacenetmask}`)
+var ipaddress = process.env.IP;
+var message = process.env.AZ;
 
 // morgan: generate apache style logs to the console
 var morgan = require('morgan')
@@ -31,28 +19,12 @@ app.use(morgan('combined'));
 // express-healthcheck: respond on /health route for LB checks
 app.use('/health', require('express-healthcheck')());
 
-// label the AZ based on which subnet we are on
-switch (network) {
-  case '10.0.100.0':
-    var az = '1a';
-    break;
-  case '10.0.101.0':
-    var az = '1b';
-    break;
-  case '10.0.102.0':
-    var az = '1c';
-    break;
-  default:
-    var az = 'unknown'
-    break;
-}
-
 // main route
 app.get('/', function (req, res) {
   res.set({
   'Content-Type': 'text/plain'
 })
-  res.send(`Node.js backend: Hello! from ${ipaddress} in AZ-${az} commit ${code_hash}`);
+  res.send(`Node.js backend: Hello! from ${message} commit ${code_hash}`);
   // res.send(`Hello World! from ${ipaddress} in AZ-${az} which has been up for ` + process.uptime() + 'ms');
 });
 

startup.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+
+set -x
+
+IP=$(hostname -i)
+NETWORK=$(echo ${IP} | cut -f3 -d.)
+
+case "${NETWORK}" in
+  100)
+    zone=a
+    color=Crimson
+    ;;
+  101)
+    zone=b
+    color=CornflowerBlue
+    ;;
+  102)
+    zone=c
+    color=LightGreen
+    ;;
+  *)
+    zone=unknown
+    color=Yellow
+    ;;
+esac
+
+# kubernetes sets routes differently -- so we will discover our IP differently
+if [[ ${IP} == "" ]]; then
+  IP=$(hostname -i)
+fi
+
+# Am I on ec2 instances?
+if [[ ${zone} == "unknown" ]]; then
+  zone=$(curl -m2 -s http://169.254.169.254/latest/dynamic/instance-identity/document | jq -r '.availabilityZone' | grep -o .$)
+fi
+
+export CODE_HASH="$(cat code_hash.txt)"
+export IP
+export AZ="${IP} in AZ-${zone}"
+
+# exec container command
+exec node server.js