WordPress on Google Cloud Run

WordPress is the world's most popular content management system, powering over 43% of all websites globally. This module deploys WordPress on Cloud Run v2 on top of the App_CloudRun foundation, which provisions and manages the shared Google Cloud infrastructure.

This guide focuses on the cloud services WordPress uses and how to explore and operate them from the Google Cloud Console and the command line. For the mechanics common to every Cloud Run application — service identity, ingress and load balancing, scaling and concurrency, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC Service Controls, backups, and the deployment lifecycle — refer to the App_CloudRun foundation guide rather than repeating them here.

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1. Overview

WordPress runs as a PHP/Apache container on Cloud Run v2. The deployment wires together a focused set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	Cloud Run v2	PHP/Apache service, 1 vCPU / 2 GiB by default, request-based autoscaling
Database	Cloud SQL for MySQL 8.0	Required — WordPress does not support PostgreSQL
Shared files	Filestore (NFS)	wp-content directory (uploads, plugins, themes) shared across all instances
Object storage	Cloud Storage	A dedicated wp-uploads media bucket
Cache	Redis	Optional object cache; enabled by default to reduce database load
Secrets	Secret Manager	Auto-generated database password and eight WordPress authentication keys and salts
Ingress	Cloud Run URL / Cloud Load Balancing	Default run.app URL, optional external HTTPS load balancer + custom domain

Sensible defaults worth knowing up front:

• MySQL 8.0 is mandatory. Selecting PostgreSQL or NONE breaks startup.
• NFS is required for a functional site. WordPress stores uploaded media, installed plugins, and active themes under wp-content/. Without a shared NFS volume, each Cloud Run revision wipes all plugins, themes, and uploads — making WordPress on Cloud Run non-functional for any real site.
• The startup probe is TCP, not HTTP. WordPress may not yet respond to HTTP requests during database initialisation on first boot; a TCP probe only checks that Apache's port is open.
• WP_HOME and WP_SITEURL are auto-set from the predicted Cloud Run service URL (CLOUDRUN_SERVICE_URL), so WordPress generates correct absolute links and avoids redirect loops.
• Database migrations run on each instance start via the db-init job; version upgrades apply schema changes automatically.
• The WordPress authentication keys and salts are auto-generated and stored in Secret Manager; you never set them in plain text.
• Cloud Run gen2 is required for NFS volume mounts.

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2. Google Cloud Services & How to Explore Them

All commands assume PROJECT and REGION are set. Service and resource names are reported in the deployment Outputs.

A. Cloud Run — the WordPress service

WordPress runs as a Cloud Run v2 service that autoscales by request load between the minimum and maximum instance counts. Each deployment creates an immutable revision; traffic can be split across revisions for safe rollouts.

• Console: Cloud Run → select the service for revisions, traffic, logs, and metrics.
• CLI:

  gcloud run services list --project "$PROJECT" --region "$REGION"
  gcloud run services describe <service-name> --project "$PROJECT" --region "$REGION"
  gcloud run revisions list --service <service-name> --project "$PROJECT" --region "$REGION"

See App_CloudRun for scaling, concurrency, execution environment, and traffic splitting.

B. Cloud SQL for MySQL 8.0

WordPress stores all site data (posts, users, settings, comments) in a managed Cloud SQL for MySQL 8.0 instance. The service connects privately through the Cloud SQL Auth Proxy over a Unix socket (no public IP). On first deploy an initialisation Job creates the application database and user.

• Console: SQL → select the instance for connections, backups, flags, metrics.
• CLI:

  gcloud sql instances list --project "$PROJECT"
  gcloud sql instances describe <instance-name> --project "$PROJECT"
  gcloud sql connect <instance-name> --user=<db-user> --project "$PROJECT"

The instance name, database, user, and password secret are in the Outputs. See App_CloudRun for the connection model, backups, and password rotation.

C. Filestore (NFS) and Cloud Storage

WordPress's wp-content directory is mapped onto a Filestore (NFS) share mounted into the service so all instances share the same plugins, themes, and uploaded media. A dedicated Cloud Storage bucket (wp-uploads) is also provisioned for media assets.

• Console: Filestore → Instances; Cloud Storage → Buckets.
• CLI:

  gcloud filestore instances list --project "$PROJECT"
  gcloud storage buckets list --project "$PROJECT"
  gcloud storage ls gs://<media-bucket>/        # bucket name is in the Outputs

See App_CloudRun for the NFS mount, GCS Fuse, and CMEK.

D. Redis object cache

Redis backs WordPress's object cache via the WP Redis plugin, storing the results of expensive database queries in memory. When redis_host is left empty and NFS is enabled, the NFS server IP is used as the Redis endpoint (the default shared deployment model).

• Console: Memorystore → Redis (if using a managed instance).
• CLI:

  redis-cli -h <redis-host> ping
  redis-cli -h <redis-host> info keyspace

E. Secret Manager

The WordPress database password and the eight WordPress authentication keys and salts are stored in Secret Manager and injected into the service at runtime; plaintext values never appear in Terraform state.

• Console: Security → Secret Manager.
• CLI:

  gcloud secrets list --project "$PROJECT"
  # List all secrets belonging to this deployment:
  gcloud secrets list --project "$PROJECT" --filter="name~<resource-prefix>"
  gcloud secrets versions access latest --secret=<secret-name> --project "$PROJECT"

See App_CloudRun for injection and rotation details.

F. Networking & ingress

The service is reachable at its run.app URL by default. An external HTTPS load balancer with a custom domain, Cloud CDN, and Cloud Armor can be layered on; ingress settings and VPC egress control connectivity.

• Console: Cloud Run (service URL); Network services → Load balancing.
• CLI:

  gcloud run services describe <service-name> --region "$REGION" --format='value(status.url)'
  gcloud compute addresses list --project "$PROJECT"

See App_CloudRun.

G. Cloud Logging & Monitoring

Container logs flow to Cloud Logging; Cloud Run and Cloud SQL metrics flow to Cloud Monitoring, with optional uptime checks and alert policies.

• Console: Logging → Logs Explorer; Monitoring → Dashboards / Alerting.
• CLI:

  gcloud run services logs read <service-name> --project "$PROJECT" --region "$REGION" --limit 50

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3. WordPress Application Behaviour

• First-deploy database setup. An initialisation Job using the mysql:8.0-debian image creates the WordPress database and user before the service starts. It runs on every tofu apply because it is idempotent — it safely skips steps that are already complete.

• Authentication keys and salts. Eight 64-character WordPress security secrets (auth key, secure auth key, logged-in key, nonce key, and their corresponding salts) are generated automatically on first deploy and stored in Secret Manager. Rotating these secrets immediately invalidates all active browser sessions — every logged-in user will be signed out.

• Site URL auto-resolution. CLOUDRUN_SERVICE_URL is always injected by the foundation with the correct Cloud Run URL. wp-config-docker.php reads this to set WP_HOME and WP_SITEURL so WordPress generates correct absolute links and avoids redirect loops behind Cloud Run.

• PHP configuration baked at build time. php_memory_limit, upload_max_filesize, and post_max_size are applied to the container image at Cloud Build time. Changing them triggers a new image build and revision.

• Health probe design. The TCP startup probe confirms Apache is listening before HTTP checks begin; the high failure_threshold (20 × 15 s = 300 s) accommodates the db-init job and WordPress's initialisation phase. The liveness probe polls /wp-admin/install.php — which returns HTTP 200 whether WordPress is freshly installed or already configured — with a 300-second initial delay.

• WordPress scheduled tasks. Cloud Run is invoked on-demand, so wp-cron pseudo-cron may not fire on schedule if there is no traffic. For reliable scheduled execution, disable wp-cron via environment_variables and configure a cron_jobs entry:

  gcloud run jobs list --project "$PROJECT" --region "$REGION"
  gcloud run jobs executions list --job <job-name> --project "$PROJECT" --region "$REGION"

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4. Configuration Variables

Variables are grouped exactly as they appear on the deployment platform. Only settings specific to or notable for WordPress are listed; every other input is inherited from App_CloudRun with its standard behaviour.

Group 1 — Project & Identity

Variable	Default	Description
project_id	(required)	Target Google Cloud project.
region	us-central1	Region for the service and regional resources.

Group 2 — Deployment Environment

Variable	Default	Description
tenant_deployment_id	demo	Short suffix that makes resource names unique per environment.
support_users	[]	Emails granted project access and monitoring alerts.
resource_labels	{}	Labels applied to all resources.

Group 3 — Application Identity

Variable	Default	Description
application_name	wordpress	Base name for resources. Do not change after first deploy.
display_name	Wordpress	Friendly name shown in the Console. Note: this module uses display_name (not application_display_name).
description	Wordpress CMS on Cloud Run	Service description.
application_version	latest	WordPress image version tag. Use a pinned version (e.g. 6.7.1) in production.
php_memory_limit	512M	PHP memory_limit baked at build time. Increase for heavy plugin workloads.
upload_max_filesize	64M	Maximum size of a single file upload. Must be ≤ post_max_size.
post_max_size	64M	Maximum size of all POST data. Must be ≥ upload_max_filesize.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
cpu_limit	1000m	CPU per instance.
memory_limit	2Gi	Memory per instance; 2 GiB recommended for WordPress with plugins.
min_instance_count	0	Minimum instances (scale-to-zero by default). Set to 1 to eliminate cold starts.
max_instance_count	1	Maximum instances. Increase only after verifying all plugins handle concurrent access correctly and NFS is enabled.
container_port	80	WordPress/Apache listens on port 80.
enable_cloudsql_volume	true	Cloud SQL Auth Proxy for socket connections. Required.
execution_environment	gen2	Cloud Run gen2 is required for NFS mounts.
traffic_split	[]	Split traffic across revisions for staged rollouts.
max_revisions_to_retain	7	How many old revisions to keep.

Group 5 — Access & Ingress Control

Variable	Default	Description
enable_iap	false	Require Google sign-in via Identity-Aware Proxy.
iap_authorized_users / iap_authorized_groups	[]	Who may access through IAP.
ingress_settings	all	Which networks may reach the service. Consider internal-and-cloud-load-balancing when using Cloud Armor.
vpc_egress_setting	PRIVATE_RANGES_ONLY	How outbound traffic is routed through the VPC connector.

Group 6 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings. WORDPRESS_TABLE_PREFIX, WORDPRESS_DEBUG, and Redis vars are set automatically.
secret_environment_variables	{}	Map of env var → Secret Manager secret name. Eight WordPress auth secrets are injected automatically.
secret_propagation_delay / secret_rotation_period	(set)	Replication wait / rotation cadence.

Group 7 — Backup & Restore

Variable	Default	Description
backup_schedule	0 2 * * *	Automated backup cron (UTC).
backup_retention_days	7	Retention; raise for production/compliance.
enable_backup_import / backup_source / backup_uri / backup_format	restore options	Restore from a backup on deploy. Note: this module uses backup_uri (full GCS URI or Drive file ID).

Group 8 — CI/CD & Binary Authorization

Standard App_CloudRun Cloud Build / Cloud Deploy integration — see App_CloudRun. Key inputs: enable_cicd_trigger, github_repository_url, github_token, enable_cloud_deploy, enable_binary_authorization.

Group 9 — Custom SQL Scripts

enable_custom_sql_scripts, custom_sql_scripts_bucket, custom_sql_scripts_path, custom_sql_scripts_use_root — run SQL from a GCS bucket after provisioning. See App_CloudRun.

Group 10 — Domain, CDN, Cloud Armor & Image Retention

Variable	Default	Description
application_domains	[]	Custom hostnames for the external load balancer.
enable_cdn	false	Enable Cloud CDN on the LB backend. Requires enable_cloud_armor = true.
enable_cloud_armor / admin_ip_ranges	off	Attach a WAF policy / restrict privileged access. Strongly recommended for public WordPress sites.
max_images_to_retain / delete_untagged_images / image_retention_days	(set)	Artifact Registry cleanup policy.

Group 11 — Storage & Filesystem

Variable	Default	Description
enable_nfs	true	Shared Filestore volume for WordPress wp-content (keep enabled).
nfs_mount_path	/mnt/nfs	Mount path inside the container. The startup script symlinks wp-content here.
create_cloud_storage / storage_buckets / gcs_volumes	(set)	Media bucket / additional buckets / GCS Fuse mounts.
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.

Group 12 — Database Backend

Variable	Default	Description
database_type	MYSQL_8_0	Fixed — do not change. WordPress requires MySQL.
db_name	wp	Database name. Immutable after first deploy. Note: this module uses db_name (not application_database_name).
db_user	wp	Application user. Immutable after first deploy. Note: this module uses db_user (not application_database_user).
database_password_length	32	Generated password length (16–64).
enable_auto_password_rotation / rotation_propagation_delay_sec	off	DB password rotation.
db_host_env_var_name / db_name_env_var_name / db_user_env_var_name / db_port_env_var_name / service_url_env_var_name	""	Additional env var names for connection details.

Group 13 — Jobs & Scheduled Tasks

Variable	Default	Description
initialization_jobs	[]	Leave empty to use the built-in db-init job.
cron_jobs	[]	Recurring Cloud Run Jobs. Use to replace wp-cron for reliable scheduled task execution.

Group 14 — Observability & Health

Variable	Default	Description
startup_probe	TCP, 30s delay, threshold 20	TCP startup probe — avoids HTTP failures during database initialisation. Do not reduce failure_threshold below 10.
liveness_probe	HTTP /wp-admin/install.php, 300s delay	300-second initial delay accommodates first-boot database setup.
uptime_check_config	disabled, path /	Cloud Monitoring uptime check.
alert_policies	[]	Metric alert policies.

Group 21 — Redis Cache

Variable	Default	Description
enable_redis	true	Use Redis for WordPress object caching.
redis_host	""	Leave empty to use the NFS server IP; set explicitly for a dedicated Memorystore instance.
redis_port	6379	Redis port.
redis_auth	""	Optional Redis auth password (sensitive).

Group 22 — VPC Service Controls & Audit Logging

Variable	Default	Description
enable_vpc_sc	false	Enforce a VPC-SC perimeter (requires organization_id).
vpc_cidr_ranges / vpc_sc_dry_run	(set)	Access level CIDRs / dry-run mode.
enable_audit_logging	false	Detailed Cloud Audit Logs.

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5. Outputs

Returned on a successful deployment — the quickest way to locate and explore the running resources.

Output	Description
service_name	Cloud Run service name.
service_url	Default run.app URL of the service.
service_location	Region the service runs in.
stage_services	Stage-specific service URLs (Cloud Deploy).
load_balancer_ip / load_balancer_url	External HTTPS load balancer IP / URL (when enabled).
database_instance_name	Cloud SQL instance name.
database_name / database_user	Application database name / user.
database_password_secret	Secret Manager secret holding the DB password.
database_host / database_port	DB endpoint / port (sensitive).
storage_buckets	Created Cloud Storage buckets.
network_name / network_exists / regions	VPC network, presence, regions.
container_image / container_registry	Deployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels / uptime_check_names	Monitoring status, channels, uptime checks.
initialization_jobs	Names of the setup jobs.
deployment_id / tenant_id / resource_prefix	Naming identifiers.
project_id / project_number	Project identifiers.
cicd_enabled / github_repository_url / github_repository_owner / github_repository_name / cicd_configuration	CI/CD status and details.
artifact_registry_repository / cloudbuild_trigger_name / cloudbuild_trigger_id	Registry and build trigger.
vpc_sc_enabled / vpc_sc_perimeter_name / vpc_sc_dry_run_mode	VPC-SC status.
audit_logging_enabled / artifact_registry_cmek_enabled	Audit logging and CMEK status.

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6. Configuration Pitfalls & Sensible Defaults

Risk: Critical (data loss / outage / security) — High (service degraded) — Medium (cost or partial degradation) — Low (minor).

Setting	Sensible value	Risk	Consequence if wrong
database_type	MYSQL_8_0	Critical	WordPress requires MySQL; PostgreSQL/NONE breaks startup.
enable_nfs	true	Critical	Without NFS, every new Cloud Run revision wipes all plugins, themes, and media uploads — WordPress is non-functional for any real site.
db_name / db_user	set once	Critical	Immutable after first deploy; renaming recreates the DB/user and destroys all WordPress data.
enable_backup_import	false unless restoring	Critical	Enabling without a valid backup_uri fails the import job.
execution_environment	gen2	High	NFS mounts require Cloud Run gen2; switching to gen1 causes a volume mount error and service startup failure.
container_image_source	custom	High	The custom WordPress image wires the NFS symlink and Cloud SQL socket. Using prebuilt with the vanilla WordPress image breaks Cloud SQL socket connectivity.
nfs_mount_path	/mnt/nfs (do not change after deploy)	High	The startup script symlinks wp-content to this path; changing it after deployment breaks the symlink.
startup_probe	TCP (default)	High	An HTTP probe may fail during first-boot database initialisation. Do not reduce failure_threshold below 10.
memory_limit	2Gi	High	WordPress with popular plugins (WooCommerce, Elementor) requires at least 2 GiB; insufficient memory causes PHP fatal errors.
enable_redis	true	Medium	Multiple instances with isolated in-memory caches cause redundant database queries.
redis_host	"" (NFS IP) or explicit	High	No valid Redis endpoint if Redis is on, NFS is off, and no host is set.
enable_cloud_armor	enable for public sites	High	WordPress login pages (/wp-login.php, xmlrpc.php) are prime brute-force targets.
php_memory_limit	512M	Medium	Must be within memory_limit; setting it higher than the container limit causes an OOM kill instead of a PHP error.
min_instance_count	1	Medium	0 causes cold-start delays and may cause visible errors for the first visitor after idle.
backup_retention_days	7 (raise for prod)	Medium	Too short for e-commerce or content-heavy sites.
enable_iap / enable_cloud_armor	enable for admin access	Medium	The WordPress admin panel is otherwise publicly reachable.

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For the foundation behaviour referenced throughout — service identity, scaling and concurrency, ingress and load balancing, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC-SC, backups, and image mirroring — see App_CloudRun. WordPress-specific application configuration shared with the GKE variant is described in Wordpress_Common.