Issue #55: Update CircleCI config to automatically deploy application

The build config now creates a new Docker image, tags it with latest, pushes it to
Google Container Registry and deploys to Google Compute Engine.

.circleci/config.yml

@@ -39,3 +39,31 @@ jobs:
 
       # run tests!
 #- run: yarn test
+  deploy:
+    docker:
+      - image: google/cloud-sdk
+    working_directory: ~/sticky-sessions-web
+    steps:
+      - checkout
+      - run: 
+          name: Setup Google Cloud SDK
+          command: scripts/setup.sh
+      - setup_remote_docker:
+          docker_layer_caching: true
+      - run: 
+          name: Docker Build, Push and Deploy
+          command: scripts/deploy.sh
+
+workflows:
+  version: 2
+  build_and_deploy:
+    jobs:
+      - build
+      - deploy:
+          requires:
+            - build
+          filters:
+            branches:
+              only: 
+                - dev
+                - master

scripts/deploy.sh

@@ -0,0 +1,52 @@
+#!/bin/sh
+
+if [ -z "$IMAGE_NAME" ]; then
+  echo "IMAGE_NAME env variable is empty. Exiting."
+  exit 1
+fi
+
+if [ -z "$GOOGLE_PROJECT_ID" ]; then
+  echo "GOOGLE_PROJECT_ID env variable is empty. Exiting."
+  exit 1
+fi
+
+# Authenticate to Google Container Registry
+gcloud auth print-access-token | docker login -u oauth2accesstoken --password-stdin https://gcr.io
+
+if [ "$CIRCLE_BRANCH" = "issue_55_cd" ]; then
+  echo "Deploying application to Staging environment"
+
+  # Injects firebase DB file
+  echo $FIREBASE_DB_STAG | base64 -di > src/db/firebaseDB/keys/index.js
+
+  # Builds Docker image
+  docker build -t ${IMAGE_NAME} .
+
+  # Tags newly created image
+  docker tag ${IMAGE_NAME} gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:stag
+
+  # Pushes image to Container Registry
+  docker push gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:stag
+
+  # Deploys application
+  gcloud --quiet compute ssh stick-sessions --zone us-east1-b -- "cd /home/app && ./restart_service.sh gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:stag"
+elif [ "$CIRCLE_BRANCH" = "master" ]; then
+  echo "Deploying application to Production environment"
+
+  # Injects firebase DB file
+  echo $FIREBASE_DB | base64 -di > src/db/firebaseDB/keys/index.js
+
+  # Builds Docker image
+  docker build -t ${IMAGE_NAME} .
+
+  # Tags newly created image
+  docker tag ${IMAGE_NAME} gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:${CIRCLE_SHA1}
+  docker tag ${IMAGE_NAME} gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:latest
+
+  # Pushes image to Container Registry
+  docker push gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:${CIRCLE_SHA1}
+  docker push gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:latest
+
+  # Deploys application
+  gcloud --quiet compute ssh stick-sessions --zone us-east1-b -- "cd /home/app && ./restart_service.sh gcr.io/${GOOGLE_PROJECT_ID}/${IMAGE_NAME}:latest"
+fi

scripts/setup.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+if [ -z "$GCLOUD_SERVICE_KEY" ]; then
+  echo "GCLOUD_SERVICE_KEY env variable is empty. Exiting."
+  exit 1
+fi
+
+if [ -z "$GOOGLE_PROJECT_ID" ]; then
+  echo "GOOGLE_PROJECT_ID env variable is empty. Exiting."
+  exit 1
+fi
+
+# Set service account key
+echo $GCLOUD_SERVICE_KEY | base64 -di > ${HOME}/gcloud-service-key.json
+
+# Authenticate gcloud
+gcloud auth activate-service-account --key-file=${HOME}/gcloud-service-key.json
+
+# Set project ID
+gcloud --quiet config set project ${GOOGLE_PROJECT_ID}