Poor man's continuous integration script, simple code deployment to Kubernetes on GCP (Google Cloud Platform)

deploy.sh

#!/bin/bash
#
# Checks Google Cloud container registry to see if build has finished deploying new image from
# source repository recent update. "GCP" stands for "Google Cloud Platform" when used below.
#
# By default, retries 9 times, waiting 45 seconds between attempts.
#
# Configure the variables at the top of the file for your environment


# NAME will print in the cli when the script runs and finishes.
NAME="My Fancy App"

# LOGO is just an image that will print in the cli when you run the script.
# Find an ascii art generator online to make something you like.
# http://patorjk.com/software/taag
#
LOGO="
 ______  ______  __   __  ______  __  __       ______  ______  ______  
/\  ___\/\  __ \/\ "-.\ \/\  ___\/\ \_\ \     /\  __ \/\  == \/\  == \ 
\ \  __\\ \  __ \ \ \-.  \ \ \___\ \____ \    \ \  __ \ \  _-/\ \  _-/ 
 \ \_\   \ \_\ \_\ \_\\"\_\ \_____\/\_____\    \ \_\ \_\ \_\   \ \_\   
  \/_/    \/_/\/_/\/_/ \/_/\/_____/\/_____/     \/_/\/_/\/_/    \/_/   
                                                                       
"

# URL is used to provide a helpful link in the console once the deployment is complete.
# The link would be clickable if your CLI supports it (iTerm2 etc).
URL="https://my-fancy-app.com/etc/"

# DEPLOYMENT is the deployment/service name in Kubernetes. Run `kubectl get services`
# to verify the name.
DEPLOYMENT="fancy-app"

# PROJECT_ID is the GCP Project ID used for deployment and source code. The default
# will look for the currently configured project using the gcloud cli. You can provide a
# static id here if desired.
PROJECT_ID="$(gcloud config get-value project)"

# IMAGE_NAME will generate a full docker/image name based on the current project id and
# current git HEAD SHA for the folder. The default is to generate the basename from the name of the repo
# configured in the remote.origin for the current folder's git information.
#
# The name must be the same in GCP Source Repositories for this to match up. It does not need to match
# the deployment/service name in kubernetes.
#
# For this to work, the name generation on the source repository build triggers must match this output:
# gcr.io/$PROJECT_ID/$REPO_NAME:$COMMIT_SHA
#
IMAGE_NAME="gcr.io/$(gcloud config get-value project)/$(basename -s .git `git config --get remote.origin.url`):$(git rev-parse HEAD)"

function fail {
  echo $1 >&2
  exit 1
}

trap 'fail "The deployment was aborted. Message -- "' ERR

function configure {
  echo "Validating configuration..."
  [ ! -z "$DEPLOYMENT" ] || fail "Configuration option is not set: DEPLOYMENT"
  [ ! -z "$PROJECT_ID" ] || fail "Configuration option is not set: PROJECT_ID"
  [ ! -z "$IMAGE_NAME" ] || fail "Configuration option is not set: IMAGE_NAME"
}

function attempt_build {
  echo "Checking build status for $IMAGE_NAME"
  local n=1
  local max=9
  local delay=45
  while true; do
    gcloud container builds list | grep $IMAGE_NAME | grep -q SUCCESS && break || {
      if [[ $n -lt $max ]]; then
        ((n++))
        echo "Build not completed. Attempt $n/$max:"
        sleep $delay;
      else
        fail "The command has failed after $n attempts."
      fi
    }
  done
}

function set_image {
  echo Container build completed, updating $DEPLOYMENT ...
  kubectl set image deployment/$DEPLOYMENT $DEPLOYMENT=$IMAGE_NAME
}

echo $LOGO

echo $NAME

configure
attempt_build
set_image
echo "Deployment complete"
echo "visit: $URL"