Build and deploy apps to Kubernetes engine

Prerequisites

1. A working Docker installation – https://store.docker.com/editions/community/docker-ce-desktop-mac
2. Google Cloud SDK gcloud – https://cloud.google.com/sdk/docs/quickstart-macos
3. Kubectl – brew install kubectl
4. Cluster credentials – In the Google Cloud Platform console, navigate to "Kubernetes engine" > "Clusters" and select "Connect" from the kebab menu.

Installing

Option 1 – prebuilt

1. Ensure you have ~/.bin directory or similar that is in your $PATH
2. Install KD:

• When using an Apple M1+ Mac run: rm -f ~/.bin/kd && curl -L $(curl -s https://api.github.com/repos/voormedia/kd/releases/latest | grep browser_download_url | grep darwin_arm64 | cut -d '"' -f 4) -o ~/.bin/kd && chmod +x ~/.bin/kd
• When using an Intel Mac run: rm -f ~/.bin/kd && curl -L $(curl -s https://api.github.com/repos/voormedia/kd/releases/latest | grep browser_download_url | grep darwin_amd64 | cut -d '"' -f 4) -o ~/.bin/kd && chmod +x ~/.bin/kd

3. Install Google Cloud credential helper:

• When using an Apple M1+ Mac run: curl -L https://github.com/GoogleCloudPlatform/docker-credential-gcr/releases/download/v2.1.0/docker-credential-gcr_darwin_arm64-2.1.0.tar.gz | tar -xzC ~/.bin docker-credential-gcr && chmod +x ~/.bin/docker-credential-gcr && docker-credential-gcr configure-docker
• When using an Intel Mac run: curl -L https://github.com/GoogleCloudPlatform/docker-credential-gcr/releases/download/v2.1.0/docker-credential-gcr_darwin_amd64-2.1.0.tar.gz | tar -xzC ~/.bin docker-credential-gcr && chmod +x ~/.bin/docker-credential-gcr && docker-credential-gcr configure-docker

Option 2 – from source

1. Make sure you have a working go installation
2. Build KD from source: go install github.com/voormedia/kd
3. Install Google Cloud credential helper: curl -L https://github.com/GoogleCloudPlatform/docker-credential-gcr/releases/download/v1.4.3/docker-credential-gcr_darwin_amd64-1.4.3.zip | funzip > ~/.bin/docker-credential-gcr && chmod +x ~/.bin/docker-credential-gcr && docker-credential-gcr configure-docker

SSH forwarding

SSH keys can be forwarded if an SSH agent is running. This is the case by default on macOS. SSH keys usually need to be added to the agent manually. For example, to expose the SSH key id_ed25519 to kd, execute the following:

ssh-add ~/.ssh/id_ed25519

In case your .ssh folder does not contain the file id_ed25519 but id_rsa, use the following command:

ssh-add ~/.ssh/id_rsa

To make sure this key is always exposed, add the following line to ~/.zshrc:

ssh-add -q ~/.ssh/id_ed25519

If you have the file id_rsa, add the following line to ~/.zshrc:

ssh-add -q ~/.ssh/id_rsa

In a Dockerfile, the SSH keys are only available for RUN commands if they opt in:

RUN --mount=type=ssh ...

Best practices for deploying

Step 1 – adjust your app

• Configure the app to run with an application server (e.g. with puma for Rails).
• Make your app log to stdout/stderr instead of log files. Preferably in Google cloud compatible JSON.

Step 2 – write a Dockerfile

• Make sure your image is small. Use a two-step build process. Use .dockerignore to exclude unused files.
• See https://github.com/voormedia/docker-base-images/tree/master/_examples for examples.

Step 3 – configure deployment

• Run kd init and input the project details.
• Review the generated configuration and adjust where necessary.

Step 4 – configure cloud services

• Create a PostgreSQL user and database if necessary. Use the same naming conventions as generated by kd in step 2. Create a secret from the service account key.

Step 5 – deploy

• Use kd deploy to deploy to a target.