Anchor Dockerfiles

A curated list of dockerfiles that act as an example repository for Anchor utility.

What is it?

This repository acts as one stop shop for all Dockerfiles & Kubernetes manifests that comprise your development environment.
Its structure is tight to Anchor requirements for proper integration.

How does it work?

Environment Variables

Anchor relies on a DOCKER_FILES environment variable that points to a local directory path containing the dockerfiles and k8s manifests.

Directory Structure

Every directory within this repository must contain the following structure:

.
├── ...
├── nginx                   # Name of the docker image/container
│   └── k8s                 # Optional: Kubernetes content
│       └── manifest.yaml   # Optional: Kubernetes manifest
│   ├── Dockerfile          # Dockerfile with build/run/tag/push instructions
│   ├── .env                # Optional: Override root `NAMESPACE` & `TAG` environment vars and/or add your own
│   └── ...                 # Optional: files for docker build
├── ... 
└── .env                    # Optional: Override default `NAMESPACE` & `TAG` environment vars and/or add your own at root level

It is recommended to back the DOCKER_FILES directory by a git repository

Affinity

It is possible to place the directory structure within a parent directory.
The parent directory name would then be treated as the directory affinity.
For example, we could place the nginx directory within a web-server parent directory.
As a result, the anchor list output shall be:

| #  | NAME      DOCKERFILE      K8S_MANIFEST      AFFINITY
| 1  | nginx        yes              yes           web-server

Customization

The following environment variables can be overridden by setting these on one of the .env files:

export NAMESPACE="my-namespace"
export TAG="v1.1.0"

Default values are anchor namespace and latest tag

Dockerfile Instructions

Every Dockerfile must have the following header is order to integrate properly to Anchor:

# OVERVIEW
# --------
# This is the Dockerfile for nginx
#
# REQUIRED BASE IMAGE TO BUILD THIS IMAGE
# ---------------------------------------
# None.
#
# REQUIRED FILES TO BUILD THIS IMAGE
# ----------------------------------
# (1) None.
#
# HOW TO BUILD THIS IMAGE
# -----------------------
# docker build -f Dockerfile \
#              -t ${NAMESPACE}/nginx:${TAG} \
#              .
#
# HOW TO RUN THIS CONTAINER
# -------------------------
# docker run -t -d \
#            -v ${HOME}/.nginx/nginx.conf:/etc/nginx/nginx:ro \
#            --name=${NAMESPACE}-nginx \
#            -p 8080:80 \
#            ${NAMESPACE}/nginx:${TAG}
#
# HOW TO TAG THIS IMAGE
# ---------------------
# docker tag ${NAMESPACE}/nginx:${TAG} \
#            ${REGISTRY}/${NAMESPACE}/nginx:${TAG}
#
# HOW TO PUSH THIS IMAGE
# ----------------------
# docker push ${REGISTRY}/${NAMESPACE}/nginx:${TAG}
#

Note:
docker tag and docker push are mandatory only if resources should be deployed to kubernetes.

Kubernetes Manifest

Anchor is using a standard kubernetes manifest.
It supports environment variables substitution within manifests using envsubst.
In order to properly expose the deployed manifest to the host, a port-forward declaration is needed on the manifest.yaml:

# HOW TO EXPOSE THIS MANIFEST
# ---------------------------
# kubectl port-forward -n ${NAMESPACE} deployment/nginx 1234:80
#

ZachiNachshon/anchor-dockerfiles