GitDocs

A GitOps approach for hosting self-updating docs on Kubernetes - similar to Netlify.

With GitDocs you can create markdown documents in a central git repository and easily access them on a Kubernetes cluster. The git sync will occur every 30 seconds and can be set with the GIT_SYNC_WAIT environment variable in examples/base/gitdocs-deployment.yaml.

GitDocs is not an application, it is the "glue" between 3 microservices (git-sync, hugo, nginx) that gains superpowers when ran in a pod on Kubernetes.

By containing the entire documentation lifecycle a pod, all you need is:

• access to a git repo
• access to a kubernetes cluster (v1.14 or later)

GitDocs is designed to run anywhere, including on-prem, and supports private or public git repositories.

Quick start

1. Clone repo

   git clone https://github.com/jimangel/GitDocs
   cd GitDocs
   

2. Apply the configmap and deployment

   The nginx.conf is created as a separate configmap to allow you to tweak any settings.

   kubectl apply -f examples/base/nginx-configmap.yaml
   kubectl apply -f examples/base/gitdocs-deployment.yaml
   

3. Use kubectl proxy to preview

   kubectl port-forward deployment/gitdocs 8080:8080
   

   Open a browser to http://localhost:8080 and browse.

Clean up

kubectl delete -f examples/base/nginx-configmap.yaml
kubectl delete -f examples/base/gitdocs-deployment.yaml

Deploy with Helm

helm repo add jimangel https://jimangel-charts.storage.googleapis.com
helm repo update

helm install gitdocs jimangel/gitdocs
# https://github.com/jimangel/GitDocs/blob/master/helm-chart/values.yaml

# use a custom website repo
helm install gitdocs jimangel/gitdocs --set gitSync.env.gitSyncRepo="https://github.com/kubernetes/website.git"

# add an ingress object
helm install gitdocs jimangel/gitdocs --set gitSync.env.gitSyncRepo="https://github.com/kubernetes/website.git" --set ingress.enabeld="true" --set ingress.hosts[0]="mysite.example.com"

# test locally
kubectl port-forward deployment/gitdocs 8080:8080

# clean up
helm delete gitdocs

# TODO: some sites are not formatted the same, the "arg" should be more dynamic to account for that.
# TODO: clean up all kustomize with helm alternatives.

Going further

From here you can create your own ingress and TLS strategy. Also, by abstracting the nginx config, you could always provide the SSL configuration to the pod.

Expose pod with a service:

kubectl expose deployment/gitdocs --port 8080

Sample ingress:

cat <<EOF | kubectl apply -f -
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: gitdocs
spec:
#  tls:
#  - hosts:
#      - gitdocs.example.com
#    secretName: gitdocs-cert
  rules:
  - http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: gitdocs
            port:
              number: 8080
EOF

Deploy with kustomize

Kustomize is a manifest generator that is build in to kubectl since version 1.14. If you're not familiar with Kustomize, please understand the following:

• example/base is where the entire deployment lives. You can take those files out and hand modify to deploy if you wanted (please don't).
• example/overlays/... is where any CHANGES live. This way, kustomize will merge the changes with the core documents before deploying.
• You can have as many different overlays as you'd like while sharing the same base

If you have internet access you can create directly with a url (no need to clone) for example:

kubectl apply -k github.com/jimangel/GitDocs//examples/overlays/kubernetes-website

Note: Depending on the size of the site it might take awhile to for the git clone. Check hugo logs to know when built.

Deploy the official Kubernetes docs

kubectl apply -k examples/overlays/kubernetes-website

# wait for the site to load (says "No Config" until GitSync is finished)
# kubectl logs -f deployment/gitdocs -c hugo

kubectl port-forward deployment/gitdocs 8080:8080
kubectl delete -k examples/overlays/kubernetes-website

Deploy the official KinD docs

kubectl apply -k examples/overlays/kind-website
kubectl port-forward deployment/gitdocs 8080:8080
kubectl delete -k examples/overlays/kind-website

Deploy the docsy example site

kubectl apply -k examples/overlays/docsy
kubectl port-forward deployment/gitdocs 8080:8080
kubectl delete -k examples/overlays/docsy

Deploy a private repo via SSH

1. Generate an SSH keypair

   ssh-keygen -f ${HOME}/git-docs-ssh
   

2. Add public key to git repo (from the GUI)

   This setting is usually in Repository settings > Deploy or Access keys)

   cat ${HOME}/git-docs-ssh.pub
   

3. Test SSH access to repository manually first

   # add the SSH key to your local user's SSH keys
   ssh-add ${HOME}/git-docs-ssh
   
   # clone repo using SSH (should NOT prompt for password - do NOT use HTTPS)
   git clone git@<GIT REPO>:<REPO PATH>.git
   

4. Create SSH key as Kubernetes secret

   # The name "git-docs-ssh-key" is important to our patch
   kubectl create secret generic git-docs-ssh-key --from-file=ssh=${HOME}/git-docs-ssh
   

5. Edit PLACEHOLDER_REPO_PATH & PLACEHOLDER_HUGO_VERSION in patch.yaml deployment patch.

   # do NOT forget to escape your URL that your replace it with by using a backslash
   sed -i.bak 's/PLACEHOLDER_REPO_PATH/git@github.com:jimangel\/examplerepo.git/' examples/overlays/private-repo/patch.yaml
   
   # update the hugo version
   sed -i.bak 's/PLACEHOLDER_HUGO_VERSION/0.104.3/' examples/overlays/private-repo/patch.yaml
   
   # if on mac
   # rm -rf examples/overlays/private-repo/patch.yaml.bak
   

6. Deploy private-repo overlay

   kubectl apply -k examples/overlays/private-repo
   kubectl port-forward deployment/gitdocs 8080:8080
   kubectl delete -k examples/overlays/private-repo
   

Troubleshooting

kubectl logs -f deployment/gitdocs -c hugo

NAMESPACE EVENTS: kubectl get events -n <NAMESPACE>

# git-sync
LOGS: kubectl logs -f deployment/gitdocs -c git-sync
EXEC: kubectl exec -it $POD -c git-sync -- /bin/sh

# hugo
LOGS: kubectl logs -f deployment/gitdocs -c hugo
EXEC: kubectl exec -it $POD -c hugo -- /bin/sh

# nginx
LOGS: kubectl logs -f deployment/gitdocs -c nginx
EXEC: kubectl exec -it $POD -c nginx -- /bin/sh d
CONFIG: kubectl edit cm nginx-conf -o yaml

Change version of Hugo

If using kustomize (see example overlays) change the hugo image tag in patch.yaml

More info: https://github.com/klakegg/docker-hugo.

Note: This might cause issues with permissions if using an image <0.70.0.

Running offline / air-gapped

There's two ways to run the klakegg/hugo container, with an edge tag or with a version tag:

• edge tag: klakegg/hugo:edge-ext-alpine
  • uses the latest container built by klakegg
  • the version is specified as a HUGO_VERISON environment variable
  • the HUGO_VERISON is downloaded from the internet when container starts
• version tag: klakegg/hugo:0.65.2-ext-alpine
  • uses the specific version in the tag and does not download from the internet
  • no need to set HUGO_VERISON environment variable

The reason GitDocs used to be built using the edge build, is because there was a issue running the container with a non-root user. This was fixed in klakegg/hugo releases >=0.70.1.

To run in an air-gapped environment, use a specific klakegg/hugo releases >=0.70.1 (ex: klakegg/hugo:0.70.1-ext-alpine).

There still might be issues running in air-gapped environments if your website content calls any external resources.

Updating

• Update kustomize examples/base/gitdocs-deployment.yaml
  • Hugo image version
  • GitSync image version
• Update kustomize patch examples
• Update helm-chart dir default values.yaml
  • tags
    • Hugo image version
    • GitSync image version
  • push
    • cd helm-chart/public
    • helm package ../
    • helm repo index . --url https://jimangel-charts.storage.googleapis.com
• Walk through each demo for correctness
• Repack helm chart
• Revise the README.md

TODO:

• Security
  • Create network policies to isolate this pod
  • More hardening / vuln scanning
• Makefile
  • for deploying, building, and updating
• Use helm to generate the base for kustomize to save effort

Thanks

A lot of this is built on top of the example present in the git-sync repo: https://github.com/kubernetes/git-sync/tree/master/demo