How this is built

# ---------------------------------------------------------------------------
# Keyless CI authentication.
#
# GitHub Actions holds no Google credential. It presents a short-lived OIDC
# token that GitHub itself signs; Workload Identity Federation verifies that
# token and exchanges it for temporary GCP credentials. There is no
# service-account JSON key in this repository, in CI secrets, or on a laptop —
# so there is nothing to leak and nothing to rotate.
# ---------------------------------------------------------------------------

resource "google_iam_workload_identity_pool" "github" {
  # Pool IDs are soft-deleted for 30 days after removal, so a typo here is
  # unusable for a month. Named deliberately.
  workload_identity_pool_id = "github-pool"
  display_name              = "GitHub Actions"
  project                   = var.project_id

  depends_on = [google_project_service.enabled]
}

resource "google_iam_workload_identity_pool_provider" "github" {
  project                            = var.project_id
  workload_identity_pool_id          = google_iam_workload_identity_pool.github.workload_identity_pool_id
  workload_identity_pool_provider_id = "github-provider"
  display_name                       = "GitHub OIDC"

  # Required, not optional. Google rejects provider creation for the GitHub
  # issuer without an attribute condition — and rightly so: an unconditioned
  # provider would accept a token from any repository on GitHub, not just mine.
  attribute_condition = "assertion.repository_owner == '${var.github_owner}'"

  attribute_mapping = {
    "google.subject"             = "assertion.sub"
    "attribute.repository"       = "assertion.repository"
    "attribute.repository_owner" = "assertion.repository_owner"
  }

  oidc {
    issuer_uri = "https://token.actions.githubusercontent.com"
  }
}

# The condition above scopes the pool to the owner. This binding narrows it
# further to one specific repository, so no other repo in the org can assume
# the deploy identity.
resource "google_service_account_iam_member" "github_impersonates_deployer" {
  service_account_id = google_service_account.deployer.name
  role               = "roles/iam.workloadIdentityUser"
  member             = "principalSet://iam.googleapis.com/${google_iam_workload_identity_pool.github.name}/attribute.repository/${var.github_owner}/${var.github_repo}"
}

# ---------------------------------------------------------------------------
# Enabled services
# ---------------------------------------------------------------------------
locals {
  services = [
    "run.googleapis.com",
    "artifactregistry.googleapis.com",
    "iamcredentials.googleapis.com",
    "sts.googleapis.com",
    "secretmanager.googleapis.com",
    "firestore.googleapis.com",
    "iam.googleapis.com",
    "storage.googleapis.com",
    # Gen-2 Cloud Functions are Cloud Run services built by Cloud Build and
    # wired through Eventarc, so all four are required even for a plain HTTP
    # function. terraform plan does not check API enablement, so a missing one
    # here surfaces only as a failed apply.
    "cloudfunctions.googleapis.com",
    "cloudbuild.googleapis.com",
    "eventarc.googleapis.com",
    "pubsub.googleapis.com",
    "monitoring.googleapis.com",
    "logging.googleapis.com",
  ]
}

resource "google_project_service" "enabled" {
  for_each = toset(local.services)
  project  = var.project_id
  service  = each.value

  # Leave the APIs on if this config is torn down; disabling them would break
  # anything else in the project that came to depend on them.
  disable_on_destroy = false
}

# ---------------------------------------------------------------------------
# Container images
# ---------------------------------------------------------------------------
resource "google_artifact_registry_repository" "images" {
  location      = var.region
  repository_id = "zayda-dev"
  description   = "Container images for zayda.dev"
  format        = "DOCKER"

  # Without this, every deploy leaves an image behind forever and storage cost
  # grows without bound.
  cleanup_policies {
    id     = "keep-recent"
    action = "KEEP"
    most_recent_versions {
      keep_count = 10
    }
  }

  cleanup_policies {
    id     = "drop-old-untagged"
    action = "DELETE"
    condition {
      tag_state  = "UNTAGGED"
      older_than = "604800s" # 7 days
    }
  }

# syntax=docker/dockerfile:1

# ---- build ----------------------------------------------------------------
# The build context is the REPOSITORY ROOT, not site/. The /stack page imports
# the real infrastructure files it renders (../../../.github/..., ../../../infra/...),
# so those files have to be inside the build. The repo layout is preserved here —
# site/ as a subdirectory, with .github/ and infra/ alongside it — so the same
# relative paths that resolve on a developer's machine resolve in the container.
FROM node:22-alpine AS build
WORKDIR /app

# Manifests first so the dependency layer caches independently of source.
COPY site/package.json site/package-lock.json ./site/
WORKDIR /app/site
RUN npm ci

# App source, plus infra/ because /stack imports the Terraform by ?raw to
# display it. The deploy workflow is deliberately not copied in.
WORKDIR /app
COPY site/ ./site/
COPY infra/ ./infra/

# Build metadata is baked in here and surfaced on /stack, which is how the page
# can prove which commit is actually serving.
ARG PUBLIC_COMMIT_SHA=local
ARG PUBLIC_BUILT_AT
ARG PUBLIC_DEPLOY_REGION=unknown
ARG PUBLIC_CONTACT_ENDPOINT=
ARG PUBLIC_COUNTER_ENDPOINT=
ARG PUBLIC_TURNSTILE_SITE_KEY=
ENV PUBLIC_COMMIT_SHA=$PUBLIC_COMMIT_SHA \
    PUBLIC_BUILT_AT=$PUBLIC_BUILT_AT \
    PUBLIC_DEPLOY_REGION=$PUBLIC_DEPLOY_REGION \
    PUBLIC_CONTACT_ENDPOINT=$PUBLIC_CONTACT_ENDPOINT \
    PUBLIC_COUNTER_ENDPOINT=$PUBLIC_COUNTER_ENDPOINT \
    PUBLIC_TURNSTILE_SITE_KEY=$PUBLIC_TURNSTILE_SITE_KEY

WORKDIR /app/site
RUN npm run build

# ---- runtime --------------------------------------------------------------
FROM nginx:1.27-alpine AS runtime

# 8080 matches the container_port Terraform declares, so Cloud Run's injected
# $PORT lines up without an entrypoint script rewriting the config.
COPY site/nginx.conf /etc/nginx/conf.d/default.conf
COPY --from=build /app/site/dist /usr/share/nginx/html

RUN adduser -D -H -u 10001 web \
 && touch /var/run/nginx.pid \
 && chown -R web:web /var/run/nginx.pid /var/cache/nginx /usr/share/nginx/html
USER web

EXPOSE 8080
CMD ["nginx", "-g", "daemon off;"]