README.md

# BigBang Template

#### _This is a mirror of a government repo hosted on [Repo1](https://repo1.dso.mil/) by [DoD Platform One](http://p1.dso.mil/).  Please direct all code changes, issues and comments to https://repo1.dso.mil/platform-one/big-bang/customers/template_**

This folder contains a template that you can replicate in your own Git repo to get started with Big Bang configuration.  If you are new to Big Bang it is recommended you start with the [Big Bang Quickstart](https://repo1.dso.mil/platform-one/quick-start/big-bang) before attempting customization.

The main benefits of this template include:

- Isolation of the Big Bang product and your custom configuration
  - Allows you to easily consume upstream Big Bang changes since you never change the product
  - Big Bang product tags are explicitly referenced in your configuration, giving you control over upgrades
- [GitOps](https://www.weave.works/technologies/gitops/) for your deployments configrations
  - Single source of truth for the configurations deployed
  - Historical tracking of changes made
  - Allows tighter control of what is deployed to production (via merge requests)
  - Enables use of CI/CD pipelines to test prior to deployment
  - Avoids problem of `helm upgrade` using `values.yaml` that are not controlled
  - Allows you to limit access to production Kubernetes cluster since all changes are made via Git
- Shared configurations across deployments
  - Common settings across deployments (e.g. dev, staging, prod) can be configured in one place
  - Secrets (e.g. pull credentials) can be shared across deployments.
    > NOTE:  SOPS [supports multiple keys for encrypting the same secret](https://dev.to/stack-labs/manage-your-secrets-in-git-with-sops-common-operations-118g) so that each environment can use a different SOPS key but share a secret.

### Prerequisites

To deploy Big Bang, the following items are required:

- Kubernetes cluster [ready for Big Bang](https://repo1.dso.mil/platform-one/big-bang/bigbang/-/blob/master/docs/d_prerequisites.md)
- A git repo for your configuration
- [Kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl/)
- [GPG (Mac users need to read this important note)](https://repo1.dso.mil/platform-one/onboarding/big-bang/engineering-cohort/-/blob/master/lab_guides/01-Preflight-Access-Checks/A-software-check.md#gpg)
- [SOPS](https://github.com/mozilla/sops)
- [Git](https://git-scm.com/book/en/v2/Getting-Started-Installing-Git)
- [Iron Bank Personal Access Token](https://registry1.dso.mil) - Under your `User Profile`, copy the `CLI secret`.
- [Repo1 Personal Access Token](https://repo1.dso.mil/-/profile/personal_access_tokens) - You will need `read_repository` permissions.

In addition, the following items are recommended to assist with troubleshooting:

- [Helm](https://helm.sh/docs/intro/install/)
- [Kustomize](https://kubectl.docs.kubernetes.io/installation/kustomize/)
- [K9S](https://github.com/derailed/k9s)

## Setup

This template supports a multi-environment template for two distinct deployments: `prod` and `dev`.  Additional environments can be added by replicating one of the existing folders.

Each environment consists of a Kubernetes manifest containing Flux resources (`bigbang.yaml`), a Kustomization file (`kustomization.yaml`), values to pass to Big Bang (`configmap.yaml`), secrets (`secrets.enc.yaml`), and additional files used to deploy resources.  All of the environments share a `base` folder to allow reusability of values between environments.

> To insure variables (e.g. `${fp}`) are set correctly, execute all of the steps below in the same terminal window.

### Create Git Repository

We need to work off our own Git repo for storing configuration.  So, you should **fork** this repo into a **private** Git repo owned by yourself or your project.  Then, clone your repo locally.

```shell
git clone https://<your domain>/<your repo>.git
cd <your repo>

# Create branch for your changes
git checkout -b template-demo
```

> It is recommended that you create your own branch so that you can [pull the original repository's `main` branch as a mirror](https://docs.gitlab.com/ee/user/project/repository/repository_mirroring.html) to keep it in sync.

### Create GPG Encryption Key

To make sure your pull secrets are not comprimized when uploaded to Git, you must generate your own encryption key:

> Keys should be created without a passphrase so that Flux can use the private key to decrypt secrets in the Big Bang cluster.

```shell
# Generate a GPG master key
# The GPG key fingerprint will be stored in the $fp variable
export fp=`gpg --quick-generate-key bigbang-sops rsa4096 encr | sed -e 's/ *//;2q;d;'`
gpg --quick-add-key ${fp} rsa4096 encr

# By default our key is set to expire in 2 years.
# Here we reduce this down to 14 days for learning/demo purposes
gpg --quick-set-expire ${fp} 14d

# Rekey the .sops.yaml
# This ensures your secrets are only decryptable by your key

## On linux
sed -i "s/pgp: FALSE_KEY_HERE/pgp: ${fp}/" .sops.yaml

## On MacOS
sed -i "" "s/pgp: FALSE_KEY_HERE/pgp: ${fp}/" .sops.yaml
```

### Add Pull Credentials

You will need pull credentials for Iron Bank to retrieve images for Big Bang.

> Secrets can be specific to an environment if they are located in that environment's folder (e.g. `prod`, `dev`).  Or, they can be shared between environments if located in the `base` directory.

``` shell
# Create a new encrypted secret to contain your pull credentials
cd base
sops secrets.enc.yaml
```

Add the following contents to the newly created sops secret.  Put your Iron Bank user/PAT where it states `replace-with-your-iron-bank-user` and `replace-with-your-iron-bank-personal-access-token`.

> The name of the secret must be `common-bb` if the secret is in the `base` folder or `environment-bb` if the secret is in the `dev` or `prod` folder.  The `environment-bb` values take precedence over the `common-bb` values.

```yaml
apiVersion: v1
kind: Secret
metadata:
   name: common-bb
stringData:
   values.yaml: |-
      registryCredentials:
      - registry: registry1.dso.mil
        username: replace-with-your-iron-bank-user
        password: replace-with-your-iron-bank-personal-access-token
```

When you save the file, it will automatically encrypt your secret using SOPS.

```shell
# Save encrypted secrets into Git
# Configuration changes must be stored in Git to take affect
git add secrets.enc.yaml ../.sops.yaml
git commit -m "chore: added encrypted credentials"
git push --set-upstream origin template-demo
```

> Your private key to decrypt these secrets is stored in your GPG key ring.  You must **NEVER** export this key and commit it to your Git repository since this would comprimise your secrets.

### Configure for GitOps

We need to reference your git repository so that Big Bang will use the configuration.  Add your repository into the `GitRepository` resource in `dev/bigbang.yaml`:

> Replace your forked Git repo where it states `replace-with-your-git-repo`.  Replace `replace-with-your-branch` with your branch name (e.g. `template-demo` as created above).

```yaml
apiVersion: source.toolkit.fluxcd.io/v1beta1
kind: GitRepository
metadata:
   name: environment-repo
   namespace: bigbang
spec:
   interval: 1m
   url: https://replace-with-your-git-repo.git
   ref:
     branch: replace-with-your-branch
   secretRef:
     name: private-git
```

> The `Kustomization` resource contains the path in your repo to the `kustomization.yaml` to start with.  If your folder changes, makes sure to update `spec.path` with the new path.

Now, save and commit your change:

```shell
git add bigbang.yaml
git commit -m "chore: updated git repo"
git push
```

## Deploy

Big Bang follows a [GitOps](https://www.weave.works/blog/what-is-gitops-really) approach to deployment.  All configuration changes will be pulled and reconciled with what is stored in the Git repository.  The only exception to this is the initial manifests (e.g. `bigbang.yaml`) which points to the Git repository and path to start from.

1. Deploy SOPS private key for Big Bang to decrypt secrets

   ```shell
   # The private key is not stored in Git (and should NEVER be stored there).  We deploy it manually by exporting the key into a secret.
   kubectl create namespace bigbang
   gpg --export-secret-key --armor ${fp} | kubectl create secret generic sops-gpg -n bigbang --from-file=bigbangkey=/dev/stdin
   ```

1. Create imagePullSecrets for Flux

   ```shell
   # Image pull secrets for Iron Bank are required to install flux.  After that, it uses the pull credentials we installed above
   kubectl create namespace flux-system

   # Adding a space before this command keeps our PAT out of our history
    kubectl create secret docker-registry private-registry --docker-server=registry1.dso.mil --docker-username=<Your IronBank Username> --docker-password=<Your IronBank Personal Access Token> -n flux-system

1. Create Git credentials for Flux

   ```shell
   # Flux needs the Git credentials to access your Git repository holding your environment
   # Adding a space before this command keeps our PAT out of our history
    kubectl create secret generic private-git --from-literal=username=<Your Repo1 Username> --from-literal=password=<Your Repo1 Personal Access Token> -n bigbang
   ```

1. Deploy Flux to handle syncing

   ```shell
   # Flux is used to sync Git with the the cluster configuration
   curl https://repo1.dso.mil/platform-one/big-bang/bigbang/-/raw/master/scripts/deploy/flux.yaml | kubectl apply -f -

   # Wait for flux to complete
   kubectl get deploy -o name -n flux-system | xargs -n1 -t kubectl rollout status -n flux-system
   ```

1. Deploy Big Bang

   ```shell
   cd ../dev
   kubectl apply -f bigbang.yaml

   # Verify 'bigbang' namespace is created
   kubectl get namespaces

   # Verify Pull from Git was successful
   kubectl get gitrepositories -A

   # Verify Kustomization was successful
   # NOTE: The Kustomization resource may fail at first with an error about the istio-system namespace.  This is normal since the Helm Release for istio will create that namespace and it has not run yet.  This should resolve itself within a few minutes
   kubectl get -n bigbang kustomizations

   # Verify secrets and configmaps are deployed
   # At a minimum, you will have the following:
   #  secrets: sops-gpg, private-git, common-bb, and environment-bb
   #  configmaps: conmmon, environment
   kubectl get -n bigbang secrets,configmaps

   # Watch deployment
   watch kubectl get hr,po -A

   # Test deployment by opening a browser to "kiali.bigbang.dev" to get to the Kiali application deployed by Istio.
   # Note that the owner of "bigbang.dev" has setup the domain to point to 127.0.0.1 for this type of testing.
   # If you are deployed on a remote host you will need to point "kiali.bigbang.dev" to your cluster master node via your /etc/hosts file
   ```

   > If you cannot get to the main page of Kiali, it may be due to an expired certificate.  Check the expiration of the certificate in `base/bigbang-dev-cert.yaml`.

   > For troubleshooting deployment problems, refer to the [Big Bang](https://repo1.dsop.io/platform-one/big-bang/bigbang) documentation.

You now have successfully deployed Big Bang.  Your next step is to customize the configuration.

## Customize

### Enable a package

1. In `dev/configmap.yaml`, enable Twistlock

   ```yaml
   twistlock:
     enabled: true
   ```

1. Push changes to Git

   ```shell
   git add configmap.yaml
   git commit -m "feat: enable twistlock"
   git push
   ```

1. Big Bang will automatically pick up your change and make the necessary changes.

   ```shell
   # Watch deployment for twislock to be deployed
   watch kubectl get hr,po -A

   # Test deployment by opening a browser to "twistlock.bigbang.dev" to get to the Twistlock application
   ```

### Update the Big Bang Version

To minimize the risk of an unexpected deployment of a BigBang release, the BigBang release version is explicitly stored in the `kustomization.yaml` files and can be updated for a planned upgrades.  The default release is stored in `base/kustomization.yaml`, but can be overridden in a specific environment like `dev/kustomization.yaml`.

- Reference for the Big Bang kustomize base:

  ```yaml
  bases:
  - https://repo1.dsop.io/platform-one/big-bang/bigbang.git/base/?ref=v1.8.0
  ```

- Reference for the Big Bang helm release:

   ```yaml
   apiVersion: source.toolkit.fluxcd.io/v1beta1
   kind: GitRepository
   metadata:
      name: bigbang
   spec:
      ref:
         $patch: replace
         semver: "1.8.0"
   ```

To update `dev/kustomization.yaml`, you would create a `mergePatch` like the following:

```yaml
patchesStrategicMerge:
- |-
  apiVersion: source.toolkit.fluxcd.io/v1beta1
  kind: GitRepository
  metadata:
    name: bigbang
  spec:
    interval: 1m
    ref:
      $patch: replace
      semver: "1.9.0"
```

> This does not update the kustomize base, but it is unusual for that to change.

Then, commit your change:

```shell
   git add kustomization.yaml
   git commit -m "feat(dev): update bigbang to 1.9.0"
   git push
```

> It may take Big Bang up to 10 minutes to recognize your changes and start to deploy them.  This is based on the interval set for polling.  You can force Big Bang to recheck by running the [sync.sh](https://repo1.dsop.io/platform-one/big-bang/bigbang/-/blob/master/hack/sync.sh) script.

It is recommended that you track Big Bang releases using the version.  However, you can use `tag` or `branch` in place of `semver` if needed.  The kustomize base uses [Go-Getter](https://github.com/hashicorp/go-getter)'s syntax for the reference.  The helm release (GitRepository) resource uses the [GitRepository CRD](https://toolkit.fluxcd.io/components/source/gitrepositories/#specification)'s syntax.

When you are done testing, you can update the reference in `base` (and delete this setting in `dev`) to update Big Bang in all environments.

> Do not forget to also update the `base/kustomization.yaml`'s `base:` reference to point to the new release.

### Update the domain

Big Bang deploys applications to `*.bigbang.dev` by default.  You can override the `bigbang.dev` domain to your domain by updating `dev/configmap.yaml` and adding the following:

```yaml
hostname: insert-your-domain-here
```

> NOTE: The `dev` template includes several overrides to minimize resource usage and increase polling time in a development environment.  They are provided for convenience and are NOT required.

Commit your change:

```shell
   git add configmap.yaml
   git commit -m "feat(dev): updated domain name"
   git push
```

### Additional Big Bang values

For additional configuration options, refer to the [Big Bang](https://repo1.dsop.io/platform-one/big-bang/bigbang) and [Big Bang Package](https://repo1.dsop.io/platform-one/big-bang/apps) documentation.

### Additional resources

Using Kustomize, you can add additional resources to the deployment if needed.  Read the [Kustomization](https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/) documentation for futher details.

## Secrets

You have already [created a GPG Encryption Key pair](#create-gpg-encryption-key) and [deployed encrypted pull credentials](#add-pull-credentials) above.  Here are some additional scenarios you may encounter with secrets.

### Key Vault

SOPS supports several key vaults to help control access to your secure keys including:

- [AWS KMS](https://github.com/mozilla/sops#27kms-aws-profiles)
- [GCP KMS](https://github.com/mozilla/sops#23encrypting-using-gcp-kms)
- [Azure Key Vault](https://github.com/mozilla/sops#24encrypting-using-azure-key-vault)
- [Hashicorp Vault](https://github.com/mozilla/sops#25encrypting-using-hashicorp-vault)

You will need to update `.sops.yaml` with your configuration based on the links above.

### Key Rotation

If you need to [rotate your GPG encryption keys](#create-gpg-encryption-key) for any reason, you will also need to re-encrypt any encrypted secrets.

1. Update `.sops.yaml` configuration file
`.sops.yaml` holds all of the key fingerpints used for SOPS.  Update `pgp`'s value to the new key's fingerprint. You can list your locally stored fingerprints using `gpg -k`.

   ```yaml
   creation_rules:
   - encrypted_regex: '^(data|stringData)$'
     pgp: INSERT_NEW_KEY_FINGERPRINT_HERE
   ```

1. Re-encrypt `secrets.enc.yaml` with your new SOPS keys.  This will decrypt the file with the old key and re-encrypt with the new key.

   ```shell
   sops updatekeys base/secrets.enc.yaml -y
   # Repeat this for all other encrypted files (e.g. dev/secrets.enc.yaml)
   ```

1. Deploy new SOPS private key for Big Bang to decrypt secrets

   ```shell
   # The private key is not stored in Git (and should NEVER be stored there).  We deploy it manually by exporting the key into a secret.
   kubectl delete secret sops-gpg -n bigbang
   gpg --export-secret-key --armor INSERT_NEW_KEY_FINGERPRINT_HERE | kubectl create secret generic sops-gpg -n bigbang --from-file=bigbangkey=/dev/stdin
   ```

1. Commit changes

   ```shell
      git add .sops.yaml **/secrets.enc.yaml
      git commit -m "chore: rekey secrets"
      git push
   ```

### Multiple Keys

You can encrypt files with SOPS using more than one key to allow different keys to decrypt the same file.  The encrypted file contains copies of the data encrypted with each key and all of the public keys needed to re-encrypt the file if changes are made.

> Only one of the private keys is required to decrypt the file

1. Add the second key's fingerprint to `.sops.yaml`:

   ```yaml
   creation_rules:
   - encrypted_regex: '^(data|stringData)$'
     pgp: ORIGINAL_KEY
         ,INSERT_SECOND_KEY_HERE
   ```

1. Re-encrypt all encrypted files with your new SOPS keys.  This will decrypt the file with the original key and re-encrypt with both of the keys.

   ```shell
   sops updatekeys base/secrets.enc.yaml -y
   # Repeat this for all other encrypted files (e.g. dev/secrets.enc.yaml)
   ```

1. Commit changes

   ```shell
      git add .sops.yaml **/secrets.enc.yaml
      git commit -m "chore: added second key to secrets"
      git push
   ```

### Different keys for different environments

In our template, we have a `dev` and a `prod` environment with a shared `base`.  Let's say we wanted the following:

- Shared Iron Bank pull credential
- Different database passwords for `dev` and `prod`
- Differnet SOPS keys for `dev` and `prod`

1. Setup `.sops.yaml` for multiple folders:

```yaml
creation_rules:
# Base is shared, so add fingerprints of both keys
- path_regex: base/.*
  encrypted_regex: '^(data|stringData)$'
  pgp: INSERT_DEV_KEY_FINGERPRINT_HERE
    ,INSERT_PROD_KEY_FINGERPRINT_HERE
- path_regex: dev/.*
  encrypted_regex: '^(data|stringData)$'
  pgp: INSERT_DEV_KEY_FINGERPRINT_HERE
- path_regex: prod/.*
  encrypted_regex: '^(data|stringData)$'
  pgp: INSERT_PROD_KEY_FINGERPRINT_HERE
```

1. Re-encrypt all encrypted files with your SOPS keys.  This will decrypt the file with the original private key and re-encrypt with the new keys according to your `path_regex`.

> If you do not have `secrets.enc.yaml` in `dev` or `prod`, you can can copy the one in `base` to test out these commands.

```shell
sops updatekeys base/secrets.enc.yaml -y
sops updatekeys dev/secrets.enc.yaml -y
sops updatekeys prod/secrets.enc.yaml -y
```

> There is an excellent tutorial on multiple key SOPS [here](https://dev.to/stack-labs/manage-your-secrets-in-git-with-sops-common-operations-118g).

1. Commit changes

   ```shell
      git add .sops.yaml **/secrets.enc.yaml
      git commit -m "chore: split dev and prod keys"
      git push
   ```

### Modifying an encrypted file

Updating values in an encrypted file can be achieved by simply opening the file with sops:

```shell
sops base/secrets.enc.yaml
```

When you save the file, sops automatically re-encrypts it for all of the keys specified in `.sops.yaml`.

## Multi-environment Workflow

In this template, we have a `dev` and `prod` environment.  Your specific situation deployment may have more.  Our intended workflow is:

- Test changes in the `dev` environment before deploying into `prod`
- Keep `dev` as close as possible to `prod` by sharing values
- Maintain `dev` and `prod` specific settings for resources, external connections, and secrets

To start, we may have the following in each folder:

- `base`
  - Iron Bank pull credentials
  - Big Bang release reference
  - Application settings
- `dev`
  - Dev domain name
  - Dev TLS certificates
  - Minimized resource values (e.g. memory, cpu)
  - Dev external connections and credentials
- `prod`
  - Prod domain name
  - Prod TLS certificates
  - Prod external connections and credentials

Big Bang `dev` value changes can be made by simply modifying `dev/configmap.yaml`.  `base` and `dev` create two separate configmaps, named `common` and `environment` respectively, with the `environment` values taking precedence over `common` values in Big Bang.

The same concept applies to `dev` secret changes, with two separate secrets named `common-bb` and `environment-bb` used for values to Big Bang, with the `environment-bb` values taking prcedence over the `common-bb` values in Big Bang.

If a new resource must be deployed, for example a TLS cert, you must add a `resources:` section to the `kustomization.yaml` to refer to the new file.  See the base directory for an example.