deploy.sh

#!/bin/bash

# The MIT License (MIT)

# Copyright (c) 2016 ScoreCI

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

set -ex

ZONE=us-central1-f

GROUP=scoreci-github-worker-group
TEMPLATE=$GROUP-tmpl
MACHINE_TYPE=f1-micro
IMAGE_FAMILY=debian-8
IMAGE_PROJECT=debian-cloud
STARTUP_SCRIPT=startup-script.sh
SCOPES="cloud-platform"
TAGS=http-server

MIN_INSTANCES=1
MAX_INSTANCES=1
TARGET_UTILIZATION=0.6

SERVICE=scoreci-github-worker

#
# Instance group setup
#

# First we have to create an instance template.
# This template will be used by the instance group
# to create new instances.
echo "Create Instance Template."
# [START create_template]
gcloud compute instance-templates create $TEMPLATE \
  --image-family $IMAGE_FAMILY \
  --image-project $IMAGE_PROJECT \
  --machine-type $MACHINE_TYPE \
  --scopes $SCOPES \
  --metadata-from-file startup-script=$STARTUP_SCRIPT \
  --tags $TAGS
# [END create_template]

# Create the managed instance group.
echo "Create Managed Instance Group."
# [START create_group]
gcloud compute instance-groups managed \
  create $GROUP \
  --base-instance-name $GROUP \
  --size $MIN_INSTANCES \
  --template $TEMPLATE \
  --zone $ZONE
# [END create_group]

# [START create_named_port]
echo "Create Named Port."
gcloud compute instance-groups managed set-named-ports \
    $GROUP \
    --named-ports http:8080 \
    --zone $ZONE
# [END create_named_port]

#
# Load Balancer Setup
#

# A complete HTTP load balancer is structured as follows:
#
# 1) A global forwarding rule directs incoming requests to a target HTTP proxy.
# 2) The target HTTP proxy checks each request against a URL map to determine the
#    appropriate backend service for the request.
# 3) The backend service directs each request to an appropriate backend based on
#    serving capacity, zone, and instance health of its attached backends. The
#    health of each backend instance is verified using either a health check.
#
# We'll create these resources in reverse order:
# service, health check, backend service, url map, proxy.

# Create a health check
# The load balancer will use this check to keep track of which instances to send traffic to.
# Note that health checks will not cause the load balancer to shutdown any instances.

# [START create_health_check]
echo "Create Health Check."
gcloud compute http-health-checks create ah-health-check \
  --request-path /_ah/health \
  --port 8080
# [END create_health_check]

# Create a backend service, associate it with the health check and instance group.
# The backend service serves as a target for load balancing.

# [START create_backend_service]
echo "Create Backend Service."
gcloud compute backend-services create $SERVICE \
  --http-health-checks ah-health-check \
  --port 8080
# [END create_backend-service]

# [START add_backend_service]
echo "Add Backend Service."
gcloud compute backend-services add-backend $SERVICE \
  --instance-group $GROUP \
  --instance-group-zone $ZONE
# [END add_backend_service]

# Create a URL map and web Proxy. The URL map will send all requests to the
# backend service defined above.

# [START create_url_map]
echo "Create URL Map."
gcloud compute url-maps create $SERVICE-map \
  --default-service $SERVICE
# [END create_url_map]

# [START create_http_proxy]
echo "Create HTTP Proxy."
gcloud compute target-http-proxies create $SERVICE-proxy \
  --url-map $SERVICE-map
# [END create_http_proxy]

# Create a global forwarding rule to send all traffic to our proxy

# [START create_forwarding_rule]
echo "Create Forwarding Rule."
gcloud compute forwarding-rules create $SERVICE-http-rule \
  --global \
  --target-http-proxy $SERVICE-proxy \
  --ports 80
# [END create_forwarding_rule]

#
# Autoscaler configuration
#
# [START set_autoscaling]
echo "Set autoscaling."
gcloud compute instance-groups managed set-autoscaling \
  $GROUP \
  --max-num-replicas $MAX_INSTANCES \
  --target-load-balancing-utilization $TARGET_UTILIZATION \
  --zone $ZONE
# [END set_autoscaling]

# [START create_firewall]
echo "Create Firewall Rules."
gcloud compute firewall-rules create default-allow-http-8080 \
    --allow tcp:8080 \
    --source-ranges 0.0.0.0/0 \
    --target-tags http-server \
    --description "Allow port 8080 access to http-server"
# [END create_firewall]
echo "Done."