Allow theme template block override

[cgopalan]

Stanford implemented the ability to override only specific named blocks of templates from a comprehensive theme, but they never contributed it upstream.

This is the PR: Stanford-Online#535

Dependencies: None

Sandbox URL: TBD - sandbox is being provisioned.

Deployment targets: edx.org and edge.edx.org

Merge deadline: None

Testing instructions:

1. Create a test theme:
   • make a directory /edx/app/edxapp/themes/testtheme
   • create a template at /edx/app/edxapp/themes/testtheme/lms/templates/dashboard.html, and put this content into it:

<%inherit file="dashboard.html" />
<%block name="pagetitle">Overridden Title!</%block>
${parent.body()}

2. After you restart the LMS, you should be able to see "Overriddden Title!" used as the page title on the student dashboard, if the patch is working correctly.

Author notes and concerns:
Note: Some templates are cached, so if you don't see the changes, you can try wiping the cache by doing rm -rf /tmp/mako_* and sudo service memcached restart.

Reviewers

• @mtyaka
• @bderusha

Settings
In lms.env.json ensure that

COMPREHENSIVE_THEME_DIRS: ["/edx/app/edxapp/themes"]
ENABLE_COMPREHENSIVE_THEMING: true
DEFAULT_SITE_THEME: "testtheme"

[openedx-webhooks]

Thanks for the pull request, @cgopalan! It looks like you're a member of a company that does contract work for edX. If you're doing this work as part of a paid contract with edX, you should talk to edX about who will review this pull request. If this work is not part of a paid contract with edX, then you should ensure that there is an OSPR issue to track this work in JIRA, so that we don't lose track of your pull request.

Create an OSPR issue for this pull request.

[cgopalan]

@mtyaka @bradenmacdonald theres one test thats failing which I am not sure why. If I run that test in my local, it fails for the master branch too. So its not related to this PR.

[cgopalan]

@mtyaka This should be ready for review again. I have added a comment explaining why it works, and also added some tests.

[mtyaka]

@cgopalan This looks great, thank you! I noticed a few typos. Can you fix those and then open an OSPR ticket, please?

[mtyaka]

typo: thats -> that's

[mtyaka]

nit: missing newline at end of file

[mtyaka]

Missing "from": "comes from the..."

[mtyaka]

Missing "from": "comes from the..."

[cgopalan]

Duh! Thanks for catching those silly errors. Must be because of the late-night work! Will fix ASAP.

[openedx-webhooks]

Thanks for the pull request, @cgopalan! I've created OSPR-1889 to keep track of it in JIRA. JIRA is a place for product owners to prioritize feature reviews by the engineering development teams.

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[cgopalan]

@mtyaka The same python tests failed as a couple of builds before - I suspect it might be due to some timezone issues, since the test is looking for a certain date (Sep 11) but finds the next day (Sep 12). Also not sure why the bokchoy job failed as I see no test failures.
Can you trigger the failed builds again?

[nedbat]

@edx/learner Who can review this?

[UmanShahzad]

@edx/learner this would be a great addition if it can get a review!

[bderusha]

This looks good! Nice work! 👍

[UmanShahzad]

@bderusha Thanks!!

[openedx-webhooks]

@cgopalan 🎉 Your pull request was merged!

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[jzoldak]

@UmanShahzad @bderusha this PR introduced xsslint violations that pushed us over the limit and master is now failing the quality build.

[bderusha]

@jzoldak Was this some kind of race condition? Shouldn't that have broken the build locally?

[jzoldak]

@bderusha Yes, I believe it was a race condition and this PR would have failed if rebased before merge. Happens occasionally.

[edx-pipeline-bot]

EdX Release Notice: This PR has been deployed to the staging environment in preparation for a release to production on Thursday, November 30, 2017.

[edx-pipeline-bot]

EdX Release Notice: This PR has been deployed to the production environment.

[edx-pipeline-bot]

EdX Release Notice: This PR has been rolled back from the production environment.

[clemente]

A newer version of this PR which fixes some issues is at https://github.com/edx/edx-platform/pull/16856