# Project Factory

This module implements in code the end-to-end project creation process for multiple projects via YAML data configurations.

It supports

- multiple project creation and management exposing the full configuration options available in the [project module](../project/), including KMS key grants and VPC-SC perimeter membership
- optional per-project [service account management](#service-accounts) including basic IAM grants
- optional [billing budgets](#billing-budgets) factory and budget/project associations
- optional per-project IaC configuration (TODO)

The factory is implemented as a thin wrapping layer, so that no "magic" or hidden side effects are implemented in code, and debugging or integration of new features are simple.

The code is meant to be executed by a high level service accounts with powerful permissions:

- Shared VPC connection if service project attachment is desired
- project creation on the nodes (folder or org) where projects will be defined

<!-- BEGIN TOC -->
- [Leveraging data defaults, merges, optionals](#leveraging-data-defaults-merges-optionals)
- [Additional resources](#additional-resources)
  - [Service accounts](#service-accounts)
  - [Billing budgets](#billing-budgets)
- [Example](#example)
- [Variables](#variables)
- [Outputs](#outputs)
- [Tests](#tests)
<!-- END TOC -->

## Leveraging data defaults, merges, optionals

In addition to the YAML-based project configurations, the factory accepts three additional sets of inputs via Terraform variables:

- the `data_defaults` variable allows defining defaults for specific project attributes, which are only used if the attributes are not passed in via YAML
- the `data_overrides` variable works similarly to defaults, but the values specified here take precedence over those in YAML files
- the `data_merges` variable allows specifying additional values for map or set based variables, which are merged with the data coming from YAML

Some examples on where to use each of the three sets are [provided below](#example).

## Additional resources

### Service accounts

Service accounts can be managed as part of each project's YAML configuration. This allows creation of default service accounts used for GCE instances, in firewall rules, or for application-level credentials without resorting to a separate Terraform configuration.

Each service account is represented by one key and a set of optional key/value pairs in the `service_accounts` top-level YAML map, which expose most of the variables available in the `iam-service-account` module:

```yaml
service_accounts:
  be-0: {}
  fe-1:
    display_name: GCE frontend service account.
    iam_self_roles:
      - roles/storage.objectViewer
    iam_project_roles:
      my-host-project:
        - roles/compute.networkUser
```

Both the `display_name` and `iam_self_roles` attributes are optional.

### Billing budgets

The project factory integrates the billing budgets factory exposed by the `[`billing-account`](../billing-account/) module, and adds support for easy referencing budgets in project files.

To enable support for billing budgets, set the billing account id, optional notification channels, and the data folder for budgets in the `factories_config.budgets` variable, then create billing budgets using YAML definitions following the format described in the `billing-account` module.

Once budgets are defined, they can be referenced in a project file using their file name:

```yaml
billing_account: 012345-67890A-BCDEF0
labels:
 app: app-1
 team: foo
parent: folders/12345678
services:
  - container.googleapis.com
  - storage.googleapis.com
billing_budgets:
  - test-100
```

The example below shows how to use the billing budgets factory.

## Example

```hcl
module "project-factory" {
  source = "./fabric/modules/project-factory"
  # use a default billing account if none is specified via yaml
  data_defaults = {
    billing_account = var.billing_account_id
  }
  # make sure the environment label and stackdriver service are always added
  data_merges = {
    labels = {
      environment = "test"
    }
    services = [
      "stackdriver.googleapis.com"
    ]
  }
  # always use this contaxt and prefix, regardless of what is in the yaml file
  data_overrides = {
    contacts = {
      "admin@example.com" = ["ALL"]
    }
    prefix = "test-pf"
  }
  # location where the yaml files are read from
  factories_config = {
    budgets = {
      billing_account   = var.billing_account_id
      budgets_data_path = "data/budgets"
      notification_channels = {
        billing-default = {
          project_id = "foo-billing-audit"
          type       = "email"
          labels = {
            email_address = "gcp-billing-admins@example.com"
          }
        }
      }
    }
    projects_data_path = "data/projects"
  }
}
# tftest modules=8 resources=37 files=prj-app-1,prj-app-2,prj-app-3,budget-test-100
```

```yaml
# project app-1
billing_account: 012345-67890A-BCDEF0
labels:
 app: app-1
 team: foo
parent: folders/12345678
service_encryption_key_ids:
 compute:
 - projects/kms-central-prj/locations/europe-west3/keyRings/my-keyring/cryptoKeys/europe3-gce
services:
  - container.googleapis.com
  - storage.googleapis.com
service_accounts:
  app-1-be:
    iam_self_roles:
    - roles/logging.logWriter
    - roles/monitoring.metricWriter
    iam_project_roles:
      my-host-project:
        - roles/compute.networkUser
  app-1-fe:
    display_name: "Test app 1 frontend."
    iam_project_roles:
      my-host-project:
        - roles/compute.networkUser
billing_budgets:
  - test-100
# tftest-file id=prj-app-1 path=data/projects/prj-app-1.yaml
```

```yaml
# project app-2
labels:
  app: app-2
  team: foo
parent: folders/12345678
org_policies:
  "compute.restrictSharedVpcSubnetworks":
    rules:
    - allow:
        values:
        - projects/foo-host/regions/europe-west1/subnetworks/prod-default-ew1
service_accounts:
  app-2-be: {}
services:
- compute.googleapis.com
- container.googleapis.com
- run.googleapis.com
- storage.googleapis.com
shared_vpc_service_config:
  host_project: foo-host
  service_identity_iam:
    "roles/vpcaccess.user":
    - cloudrun
    "roles/container.hostServiceAgentUser":
    - container-engine
  service_identity_subnet_iam:
    europe-west1/prod-default-ew1:
    - cloudservices
    - container-engine
  network_subnet_users:
    europe-west1/prod-default-ew1:
    - group:team-1@example.com

# tftest-file id=prj-app-2 path=data/projects/prj-app-2.yaml
```

```yaml
# project app-3
parent: folders/12345678
services:
- run.googleapis.com
- storage.googleapis.com

# tftest-file id=prj-app-3 path=data/projects/prj-app-3.yaml
```

```yaml
# billing budget test-100
display_name: 100 dollars in current spend
amount:
  units: 100
filter:
  period:
    calendar: MONTH
  resource_ancestors:
  - folders/1234567890
threshold_rules:
- percent: 0.5
- percent: 0.75
update_rules:
  default:
    disable_default_iam_recipients: true
    monitoring_notification_channels:
    - billing-default
# tftest-file id=budget-test-100 path=data/budgets/test-100.yaml
```
<!-- BEGIN TFDOC -->
## Variables

| name | description | type | required | default |
|---|---|:---:|:---:|:---:|
| [factories_config](variables.tf#L91) | Path to folder with YAML resource description data files. | <code title="object&#40;&#123;&#10;  projects_data_path &#61; string&#10;  budgets &#61; optional&#40;object&#40;&#123;&#10;    billing_account       &#61; string&#10;    budgets_data_path     &#61; string&#10;    notification_channels &#61; optional&#40;map&#40;any&#41;, &#123;&#125;&#41;&#10;  &#125;&#41;&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> | ✓ |  |
| [data_defaults](variables.tf#L17) | Optional default values used when corresponding project data from files are missing. | <code title="object&#40;&#123;&#10;  billing_account            &#61; optional&#40;string&#41;&#10;  contacts                   &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;  labels                     &#61; optional&#40;map&#40;string&#41;, &#123;&#125;&#41;&#10;  metric_scopes              &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;  parent                     &#61; optional&#40;string&#41;&#10;  prefix                     &#61; optional&#40;string&#41;&#10;  service_encryption_key_ids &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;  service_perimeter_bridges  &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;  service_perimeter_standard &#61; optional&#40;string&#41;&#10;  services                   &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;  shared_vpc_service_config &#61; optional&#40;object&#40;&#123;&#10;    host_project                &#61; string&#10;    network_users               &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;    service_identity_iam        &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;    service_identity_subnet_iam &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;    service_iam_grants          &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;    network_subnet_users        &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;  &#125;&#41;, &#123; host_project &#61; null &#125;&#41;&#10;  tag_bindings &#61; optional&#40;map&#40;string&#41;, &#123;&#125;&#41;&#10;  service_accounts &#61; optional&#40;map&#40;object&#40;&#123;&#10;    display_name   &#61; optional&#40;string, &#34;Terraform-managed.&#34;&#41;&#10;    iam_self_roles &#61; optional&#40;list&#40;string&#41;&#41;&#10;  &#125;&#41;&#41;, &#123;&#125;&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
| [data_merges](variables.tf#L49) | Optional values that will be merged with corresponding data from files. Combines with `data_defaults`, file data, and `data_overrides`. | <code title="object&#40;&#123;&#10;  contacts                   &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;  labels                     &#61; optional&#40;map&#40;string&#41;, &#123;&#125;&#41;&#10;  metric_scopes              &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;  service_encryption_key_ids &#61; optional&#40;map&#40;list&#40;string&#41;&#41;, &#123;&#125;&#41;&#10;  service_perimeter_bridges  &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;  services                   &#61; optional&#40;list&#40;string&#41;, &#91;&#93;&#41;&#10;  tag_bindings               &#61; optional&#40;map&#40;string&#41;, &#123;&#125;&#41;&#10;  service_accounts &#61; optional&#40;map&#40;object&#40;&#123;&#10;    display_name   &#61; optional&#40;string, &#34;Terraform-managed.&#34;&#41;&#10;    iam_self_roles &#61; optional&#40;list&#40;string&#41;&#41;&#10;  &#125;&#41;&#41;, &#123;&#125;&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |
| [data_overrides](variables.tf#L69) | Optional values that override corresponding data from files. Takes precedence over file data and `data_defaults`. | <code title="object&#40;&#123;&#10;  billing_account            &#61; optional&#40;string&#41;&#10;  contacts                   &#61; optional&#40;map&#40;list&#40;string&#41;&#41;&#41;&#10;  parent                     &#61; optional&#40;string&#41;&#10;  prefix                     &#61; optional&#40;string&#41;&#10;  service_encryption_key_ids &#61; optional&#40;map&#40;list&#40;string&#41;&#41;&#41;&#10;  service_perimeter_bridges  &#61; optional&#40;list&#40;string&#41;&#41;&#10;  service_perimeter_standard &#61; optional&#40;string&#41;&#10;  tag_bindings               &#61; optional&#40;map&#40;string&#41;&#41;&#10;  services                   &#61; optional&#40;list&#40;string&#41;&#41;&#10;  service_accounts &#61; optional&#40;map&#40;object&#40;&#123;&#10;    display_name   &#61; optional&#40;string, &#34;Terraform-managed.&#34;&#41;&#10;    iam_self_roles &#61; optional&#40;list&#40;string&#41;&#41;&#10;  &#125;&#41;&#41;&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>&#123;&#125;</code> |

## Outputs

| name | description | sensitive |
|---|---|:---:|
| [projects](outputs.tf#L17) | Project module outputs. |  |
| [service_accounts](outputs.tf#L22) | Service account emails. |  |
<!-- END TFDOC -->
## Tests

These tests validate fixes to the project factory.

```hcl
module "project-factory" {
  source = "./fabric/modules/project-factory"
  data_defaults = {
    billing_account = "012345-67890A-ABCDEF"
  }
  data_merges = {
    labels = {
      owner = "foo"
    }
    services = [
      "compute.googleapis.com"
    ]
  }
  data_overrides = {
    prefix = "foo"
  }
  factories_config = {
    projects_data_path = "data/projects"
  }
}
# tftest modules=4 resources=14 files=test-0,test-1,test-2
```

```yaml
parent: folders/1234567890
services:
  - iam.googleapis.com
  - contactcenteraiplatform.googleapis.com
  - container.googleapis.com
# tftest-file id=test-0 path=data/projects/test-0.yaml
```

```yaml
parent: folders/1234567890
services:
  - iam.googleapis.com
  - contactcenteraiplatform.googleapis.com
# tftest-file id=test-1 path=data/projects/test-1.yaml
```

```yaml
parent: folders/1234567890
services:
  - iam.googleapis.com
  - storage.googleapis.com
# tftest-file id=test-2 path=data/projects/test-2.yaml
```
