built with concourse

OVERVIEW

Every 2 seconds this App will print,

    INFO[0000] Let's Start this!
    Hello everyone, count is: 1
    Hello everyone, count is: 2
    Hello everyone, count is: 3
    etc...

PREREQUISITES

You will need the following go packages,

go get -u -v github.com/sirupsen/logrus
go get -u -v github.com/cweill/gotests/...

This repo contains the packer gce image build scripts,

git clone git@github.com:JeffDeCola/my-packer-image-builds.git

SOFTWARE STACK

RUN

To run.sh,

cd hello-go-deploy-gce-code
go run main.go

To create-binary.sh,

cd hello-go-deploy-gce-code/bin
go build -o hello-go ../main.go
./hello-go

This binary will not be used during a docker build since it creates it’s own.

STEP 1 - TEST

To create unit _test files,

cd hello-go-deploy-gce-code
gotests -w -all main.go

To run unit-tests.sh,

go test -cover ./... | tee test/test_coverage.txt
cat test/test_coverage.txt

STEP 2 - BUILD (DOCKER IMAGE VIA DOCKERFILE)

This docker image is built in two stages. In stage 1, rather than copy a binary into a docker image (because that can cause issues), the Dockerfile will build the binary in the docker image. In stage 2, the Dockerfile will copy this binary and place it into a smaller docker image based on alpine, which is around 13MB.

To build.sh with a Dockerfile,

cd hello-go-deploy-gce-code/build
docker build -f Dockerfile -t jeffdecola/hello-go-deploy-gce .

You can check and test this docker image,

docker images jeffdecola/hello-go-deploy-gce
docker run --name hello-go-deploy-gce -dit jeffdecola/hello-go-deploy-gce
docker exec -i -t hello-go-deploy-gce /bin/bash
docker logs hello-go-deploy-gce
docker rm -f hello-go-deploy-gce

STEP 3 - PUSH (TO DOCKERHUB)

You must be logged in to DockerHub,

docker login

To push.sh,

docker push jeffdecola/hello-go-deploy-gce

Check the hello-go-deploy-gce docker image at DockerHub.

STEP 4 - DEPLOY (TO GCE)

There are three steps to deploy on gce,

For this example, I will add two running services,

To keep things simple, the files are located in my my-packer-image-builds repo.

STEP 4.1 BUILD A CUSTOM MACHINE IMAGE USING PACKER

You will need to set the following environment variables (I added mine in ~/.bashrc),

export GCP_JEFFS_SERVICE_ACCOUNT_PATH=[path to your google platform .json file]
export GCP_JEFFS_PROJECT_ID=[your project id]

To validate your packer template file template.pkr.hcl,

cd my-packer-image-builds/google-compute-engine-images/jeffs-gce-image-ubuntu-2204
packer validate \
    -var "image_name=hello-go-deploy-gce" \
    -var "account_file=$GCP_JEFFS_SERVICE_ACCOUNT_PATH" \
    -var "project_id=$GCP_JEFFS_PROJECT_ID" \
    template.pkr.hcl

To build-image.sh on gce,

cd my-packer-image-builds/google-compute-engine-images/jeffs-gce-image-ubuntu-2204
packer build \
    -var "image_name=hello-go-deploy-gce" \
    -var "account_file=$GCP_JEFFS_SERVICE_ACCOUNT_PATH" \
    -var "project_id=$GCP_JEFFS_PROJECT_ID" \
    template.pkr.hcl

Check that the image was created at gce,

gcloud config set project $GCP_JEFFS_PROJECT_ID
gcloud compute images list --no-standard-images

STEP 4.2 CREATE AN INSTANCE TEMPLATE

The instance template contains the HW resources the instance group needs to create the VM instance.

To create-instance-template,

cd my-packer-image-builds/google-compute-engine-images/jeffs-gce-image-ubuntu-2204
sh create-instance-template.sh "jeffs-hello-go-deploy-gce-image" "hello-go-deploy-gce"

Check the instance template was created,

gcloud compute instance-templates list

STEP 4.3 CREATE AN INSTANCE GROUP

The instance group controls the show. It launches and scales your VM instances as needed.

To create-instance-group,

cd my-packer-image-builds/google-compute-engine-images/jeffs-gce-image-ubuntu-2204
sh create-instance-group.sh "jeffs-hello-go-deploy-gce-instance-template" "hello-go-deploy-gce"

Check that the instance group and VM instance were created,

gcloud compute instance-groups list
gcloud compute instances list

CHECK SERVICES ARE RUNNING

To ssh into your gce VM, I placed my public keys in gce metadata ssh keys, which automatically places them in the authorized_keys files on my VM,

ssh -i ~/.ssh/google_compute_engine jeff@<IP>

Check the docker service is running,

docker ps
docker logs -f --tail 10 -f hello-go-deploy-gce

Check that your hello-go.service is running,

# Remember, it kicks off /home/jeff/hello-go
systemctl list-unit-files | grep hello.go
sudo systemctl status hello-go
journalctl -f
sudo systemctl stop hello-go
cat /lib/systemd/system/hello-go.service
sudo -s

Last, if you have multiple VMS, and since you put the same ssh keys in /home/jeff/.ssh when you built the image with packer, your VMs can talk to each other using gce’s internal DNS.

ssh <USERNAME>@<HOSTNAME>.us-west1-a.c.<PROJECT>.internal

CONTINUOUS INTEGRATION & DEPLOYMENT

Refer to ci-README.md on how I automated the above steps using concourse.