Deployments

Trellis allows zero-downtime WordPress deployment out of the box with a little configuration. Hooks let you customize what happens at each step of the deploy process.

Trellis deploys your site from a Git repository. In your wordpress_sites.yml file, found in the group_vars/<environment> directory, make sure the repo and branch keys are set correctly:

• repo - Git URL of your Bedrock-based WordPress project (in SSH format: git@github.com:org/repo-name.git)
• branch - Git branch to deploy (default: master)

wordpress_sites:
  example.com:
    ...
-   repo: git@github.com:example/example.com.git
+   repo: git@github.com:org/repo-name.git
-   branch: master
+   branch: main

Read more about WordPress Sites in Trellis

# Deploying

Run the following from any directory within your project:

trellis deploy <environment>

# Rollbacks

Run the following from any directory within your project:

trellis rollback <environment>

Manually specify a different release using --release=12345678901234 as such:

trellis rollback --release=12345678901234 <environment>

By default Trellis stores five previous releases, not including the current release. See deploy_keep_releases in Options - Remote Servers to change this setting.

# Hooks

Trellis deploys let you customize what happens at each step of the atomic deployment process. A single deploy has the following steps in order:

1. initialize - creates the site directory structure (or ensures it exists)
2. update - clones the Git repo onto the remote server
3. prepare - prepares the files/directories in the new release path (such as moving the repo subtree if one exists)
4. build - builds the new release by copying templates, files, and folders
5. share - symlinks shared files/folders to new release
6. finalize - finalizes the deploy by updating the current symlink (atomic deployments)

Each step has a before and after hook. The hooks are variables that you can define with a list of custom task files to be included and run when the hook fires.

The hook variables available are:

• deploy_before
• deploy_initialize_before
• deploy_initialize_after
• deploy_update_before
• deploy_update_after
• deploy_prepare_before
• deploy_prepare_after
• deploy_build_before
• deploy_build_after
• deploy_share_before
• deploy_share_after
• deploy_finalize_before
• deploy_finalize_after
• deploy_after

# Default hooks

By default, Trellis defines and uses three hooks:

• deploy_build_after runs composer install.
• deploy_finalize_before checks the WordPress installation.
• deploy_finalize_after refreshes WordPress settings and reloads php-fpm.

The default deploy hooks are defined in roles/deploy/defaults/main.yml:

deploy_build_before:
  - '{{ playbook_dir }}/deploy-hooks/build-before.yml'

deploy_build_after:
  - '{{ playbook_dir }}/roles/deploy/hooks/build-after.yml'
  # - "{{ playbook_dir }}/deploy-hooks/sites/{{ site }}-build-after.yml"

deploy_finalize_before:
  - '{{ playbook_dir }}/roles/deploy/hooks/finalize-before.yml'

deploy_finalize_after:
  - '{{ playbook_dir }}/roles/deploy/hooks/finalize-after.yml'

The deploy_build_before definition and the commented path under deploy_build_after offer examples of using hooks for custom tasks, as described below.

# Custom tasks

To use a deploy hook, define or override the hook variable somewhere within your group_vars directory, such as in group_vars/all/main.yml. If you end up defining many hooks, you may want to create a new file such as group_vars/all/deploy-hooks.yml.

Each deploy hook variable is a list of task files to be included and run when the hook fires. We suggest keeping your hooked task files in a top level deploy-hooks folder. Here are some example hook variable definitions:

# Defining a hook that Trellis does not already use by default
deploy_before:
  - '{{ playbook_dir }}/deploy-hooks/deploy-before.yml'

# Overriding a hook that Trellis already uses by default
deploy_build_after:
  - '{{ playbook_dir }}/roles/deploy/hooks/build-after.yml'
  - '{{ playbook_dir }}/deploy-hooks/build-after.yml'
  - '{{ playbook_dir }}/deploy-hooks/sites/{{ site }}-build-after.yml'

The second example above demonstrates overriding the deploy_build_after hook that Trellis already uses by default. The first include file in this hook's list is roles/deploy/hooks/build-after.yml, which is the task file Trellis usually executes. If you omit a hook's default file when overriding an existing hook variable, the default file's tasks will no longer execute.

The second include file in the deploy_build_after example above, deploy-hooks/build-after.yml, is an example of adding a custom task file that would run on every deploy, regardless the site being deployed. The third include file, deploy-hooks/sites/{{ site }}-build-after.yml, demonstrates how you could use a {{ site }} variable to include a file based on the name of the site being deployed, e.g., example.com-build-after.yml.