GCP-Project-Pipeline

A goldilocks effort for bootstraping a GCP project with it's own ci/cd pipeline:

Inspired by these great repos:

Why?

The healthcare data protection suite is great at making a simple project that gets you a functional ci/cd pipeline for terraforming GCP all using GCP resources. However, it's templated terraform eminating from a golang engine. This project cuts to the chase using just terraform.

The terraform example foundation is about building a complete GCP org, not an individual project and can be overkill. It also doesn't setup source control/triggers for the cicd pipeline itself, which is odd.

This is meant to simply satisfy the urge to dream up a project, give it a name and location in the org tree, terraform apply and then immediately begin using the ci/cd pipeline to build the remaining infrastructure.

Continuous integration (CI) and continuous deployment (CD)

The CI and CD pipelines use Google Cloud Build and Cloud Build triggers to detect changes in a cloud source repo, trigger builds, and implement terraform changes.

Concept of operations

The desired end state is a GCP project with a cloud source repo and cloud build triggers that terraform plan/apply on code commits. The build triggers will run terraform against a list of directories you choose (cicd by default) so you can use it to build the pipeline, infrastructure, groups, compute, databases, iam, etc as separate concerns as you see fit.

The _managed_dirs list in the triggers.tf file in the cicd directory sets the directories that will be managed by this cicd pipeline.

Setup

You will need to be able to create a project with billing in the appropriate place in your particular org structure. First you'll run terraform locallly to initialize the project and the pipeline. After the project is created, we will transfer terraform state to the cloud bucket and from then on you can use git commits to trigger terraform changes without any local resources or permissions.

Clone this repo
Change directory (cd) to the cicd directory and edit the terraform.tfvars to match your GCP organization.
Run the following commands in the cicd directory to enable the necessary APIs, grant the Cloud Build service account the necessary permissions, and create Cloud Build triggers and the terraform state bucket:
```
terraform init
terraform apply
```
Get the name of the terraform state bucket from the terraform output
```
terraform output
```

and copy backend.tf.example as backend.tf with the proper bucket name.

```terraform
    terraform {
  backend "gcs" {
    bucket = "UPDATE_ME_WITH_OUTPUT_OF_INITIAL_INIT"
    prefix = "cicd"
  }
}
```

Note that if you create other directories for other terraform concerns, you should duplicate this backend.tf file in those directories with a different prefix so your state bucket matches your directory layout.

Now terraform can transfer state from your local environment into GCP. From the cicd directory:
```
terraform init -force-copy
```

Follow the instructions at https://source.cloud.google.com// to then push your code (from the parent directory of cicd, i.e. not the cicd directory) into your new CICD pipeline. Basically:

git init
gcloud init && git config --global credential.https://source.developers.google.com.helper gcloud.sh
git remote add google  https://source.developers.google.com/p/<project name>/r/<repository name>
git checkout -b main
git add cicd/configs/* cicd/backend.tf cicd/main.tf cicd/outputs.tf cicd/terraform.tfvars cicd/triggers.tf cicd/variables.tf
git commit -m 'first push after bootstrap'
git push --all google

After the repo and pipeline is established you should be able to view the build triggers and history by visiting: https://console.cloud.google.com/cloud-build/dashboard?project=

Group Management

If you would like to enable your pipeline to manage groups and memberships for you:
1. Make sure directories which contain the groups resources are included in the _managed_dirs list in the triggers.tf file in the cicd directory.
2. Grant Google Workspace Group Editor role to the CICD service account <project-number>@cloudbuild.gserviceaccount.com by following the following steps:
  1. Go to Google Admin console's Admin roles configuration page https://admin.google.com/u/1/ac/roles
  2. Click Groups Editor;
  3. Click Admins assigned;
  4. Click Assign service accounts and input the CICD service account email address.
Alternatively, follow steps here.

In either approach, you must be a Google Workspace Super Admin to be able to complete those steps.

CICD Container

The Docker container used for CICD executions are built and maintained by the Cloud Foundation Toolkit (CFT) team. Documentations and scripts can be found here. This container includes necessary dependencies (e.g. bash, terraform, gcloud) to validate and deploy Terraform configs. If you would like to use a different container for production deployment, you can modify the Cloud Build YAML files in ./configs directory to point to your container.

This leverages Google Container Registry's Vulnerability scanning feature to detect potential security risks in this container, and None is reported.

Features

Event-triggered builds

Two presubmit and one postsubmit triggers are created by default.

[Presubmit] tf-validate: Perform Terraform format and syntax check.
- It does not access Terraform remote state.
[Presubmit] tf-plan: Generate speculative plans to show a set of potential changes if the pending config changes are deployed.
- It accesses Terraform remote state but does not lock it.
- This also performs a non-blocking check for resource deletions. These are worth reviewing, as deletions are potentially destructive.
[Postsubmit] tf-apply: Apply the terraform configs that are checked into the config source repo.
- It accesses Terraform remote state and locks it.
- This trigger is only applicable post-submit.
- When this trigger is set in the Terraform engine config, the Cloud Build service account is given broader permissions to be able to make changes to the infrastructure.

Every new push to the Pull Request at the configured branches automatically triggers presubmit runs.

The postsubmit Cloud Build job automatically starts after a Pull Ruquest is submitted to a configured branch. To view the result of the Cloud Build run, go to Build history and look for your commit to view the Cloud Build job triggered by your merged commit.

The build_viewers members can view detailed log output.

The triggers all use a helper runner script to perform actions. The DIRS var within the script lists the directories that are managed by the triggers and the order they are run.

Deletion check allowlist

The deletion check run as part of the tf-plan trigger optionally accepts an allowlist of resources to ignore, using grep extended regex patterns matched against the Terraform resource address from the plan.

To configure an allowlist:

Create a file tf-deletion-allowlist.txt in the cicd/configs/ directory.
Add patterns to it, one per line.

Example:

network
^module.cloudsql.module.safer_mysql.google_sql_database.default$
google_sql_user.db_users\["user-creds"\]

Each line allows, respectively:

Any resource whose address contains the string "network".
A specific resource within a module.
A specific resource with a generated name, i.e. from for_each or count.

qwhiz/gcp-project-pipeline