Deploys: Update WP theme paths for multisite subsites

[fullyint]

This PR is the final piece of the former #848 and addresses https://discourse.roots.io/t/multisite-subsite-using-twentyfifteen-theme/9871/5. This PR enables Trellis deploys to update template_root and stylesheet_root WP options also for multisite subsites, not just the primary site.

To disable: Multisite operators who wish to avoid the processing time may define update_wp_theme_paths: false in a group_vars file or on the fly:

ansible-playbook deploy.yml -e env=production -e site=example.com -e update_wp_theme_paths=false

Implementation notes

xargs for multisite. See also https://danielbachhuber.com/tip/run-wp-cli-command-wordpress-multisite/

bool filter is necessary for proper interpretation of cli -e update_wp_theme_paths=false (otherwise the var remains a string "false" interpreted as boolean true).

select statement in with_subelements limits the items executed instead of via the when condition. This prevents skipped output, which could otherwise be very lengthy if an installation has many subsites. Consider a multisite installation with only two sites. When one site is changed and one is skipped, this PR's output contains only this:

TASK [deploy : Update WP theme paths] *************************************************************
changed: [test] => (item=({'option': 'template_root'}, u'http://test2.example.test/ /srv/www/exampl
e.com/releases/20170730231750/web/wp/wp-content/themes'))

changed: [test] => (item=({'option': 'stylesheet_root'}, u'http://test2.example.test/ /srv/www/exam
ple.com/releases/20170730231750/web/wp/wp-content/themes'))

Compare output from using a when condition instead of the select statement in with_subelements:

TASK [deploy : Update WP theme paths] *************************************************************
skipping: [test] => (item=({'_ansible_parsed': True, 'stderr_lines': [], '_ansible_item_result': Tr
ue, u'end': u'2017-07-30 23:18:16.665821', '_ansible_no_log': False, u'stdout': u'http://example.te
st/wp/ \nhttp://test2.example.test/ /srv/www/example.com/releases/20170730190452/web/wp/wp-content/
themes', u'cmd': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n "$url
 " && wp option get template_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u'rc': 0, 
'item': u'template_root', u'delta': u'0:00:01.619913', u'stderr': u'', u'changed': False, u'invocat
ion': {u'module_args': {u'warn': True, u'executable': None, u'chdir': u'/srv/www/example.com/curren
t', u'_raw_params': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n "$
url " && wp option get template_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u'remov
es': None, u'creates': None, u'_uses_shell': True}}, 'failed_when_result': False, u'start': u'2017-
07-30 23:18:15.045908', 'failed': False}, u'http://example.test/wp/ '))

changed: [test] => (item=({'_ansible_parsed': True, 'stderr_lines': [], '_ansible_item_result': Tru
e, u'end': u'2017-07-30 23:18:16.665821', '_ansible_no_log': False, u'stdout': u'http://example.tes
t/wp/ \nhttp://test2.example.test/ /srv/www/example.com/releases/20170730190452/web/wp/wp-content/t
hemes', u'cmd': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n "$url 
" && wp option get template_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u'rc': 0, '
item': u'template_root', u'delta': u'0:00:01.619913', u'stderr': u'', u'changed': False, u'invocati
on': {u'module_args': {u'warn': True, u'executable': None, u'chdir': u'/srv/www/example.com/current
', u'_raw_params': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n "$u
rl " && wp option get template_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u'remove
s': None, u'creates': None, u'_uses_shell': True}}, 'failed_when_result': False, u'start': u'2017-0
7-30 23:18:15.045908', 'failed': False}, u'http://test2.example.test/ /srv/www/example.com/releases
/20170730190452/web/wp/wp-content/themes'))

skipping: [test] => (item=({'_ansible_parsed': True, 'stderr_lines': [], '_ansible_item_result': Tr
ue, u'end': u'2017-07-30 23:18:19.421725', '_ansible_no_log': False, u'stdout': u'http://example.te
st/wp/ \nhttp://test2.example.test/ /srv/www/example.com/releases/20170730190452/web/wp/wp-content/
themes', u'cmd': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n "$url 
" && wp option get stylesheet_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u'rc': 0
, 'item': u'stylesheet_root', u'delta': u'0:00:01.708665', u'stderr': u'', u'changed': False, u'inv
ocation': {u'module_args': {u'warn': True, u'executable': None, u'chdir': '/srv/www/example.com/cu
rrent', u'_raw_params': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -
n "$url " && wp option get stylesheet_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u
'removes': None, u'creates': None, u'_uses_shell': True}}, 'failed_when_result': False, u'start': u
'2017-07-30 23:18:17.713060', 'failed': False}, u'http://example.test/wp/ '))

changed: [test] => (item=({'_ansible_parsed': True, 'stderr_lines': [], '_ansible_item_result': Tru
e, u'end': u'2017-07-30 23:18:19.421725', '_ansible_no_log': False, u'stdout': u'http://example.tes
t/wp/ \nhttp://test2.example.test/ /srv/www/example.com/releases/20170730190452/web/wp/wp-content/t
hemes', u'cmd': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n "$url 
" && wp option get stylesheet_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u'rc': 0,
 'item': u'stylesheet_root', u'delta': u'0:00:01.708665', u'stderr': u'', u'changed': False, u'invo
cation': {u'module_args': {u'warn': True, u'executable': None, u'chdir': u'/srv/www/example.com/cur
rent', u'_raw_params': u' wp site list --field=url | xargs -I {} bash -c \'export url="{}"; echo -n
 "$url " && wp option get stylesheet_root --skip-plugins --skip-themes --url=$url || echo\'\n ', u
'removes': None, u'creates': None, u'_uses_shell': True}}, 'failed_when_result': False, u'start': u
'2017-07-30 23:18:17.713060', 'failed': False}, u'http://test2.example.test/ /srv/www/example.com/re
leases/20170730190452/web/wp/wp-content/themes'))

The above is for two sites only. Imagine output above for a multisite installation with 50+ subsites.

[fullyint]

I added two commits:

Deploys: Minimize delay in updating WP theme paths

After a new release path is symlinked, sites that need WP theme paths updated won't load until updated, a window of 1-10+ seconds. Thanks @karex for pointing this out.

This commit shuffles tasks so the update task runs as quickly as possible after symlink change.

Remove WP transient _site_transient_theme_roots during deploys

WP options template_root and stylesheet_root will not exist for a site when no theme has been activated explicitly, when a site defaults to a theme like twentyseventeen. In this case, WP consults the _site_transient_theme_roots transient for the path to the theme. This transient contains release paths that do not update on deploy, leading to WSOD due to various instances of "No such file or directory." Original examination in #275 (comment).

This commit avoids the problem by removing the _site_transient_theme_roots transient immediately after the new release path is symlinked. WP regenerates the transient with correct paths as needed.

[swalkinshaw]

🚀