Issue #26: Fix 'Use local library' option.

[alxp]

GitHub Issue: #26

What does this Pull Request do?

Fix broken option to use a local instance of Mirador Integration Islandora.

What's new?

1. Add a more helpful description to the use local library option on the Islandora Mirador admin settings page.
2. Fix the library info alter hook to work correctly and not just accidentally.

• Does this change add any new dependencies? No
• Does this change require any other modifications to be made to the repository
  (i.e. Regeneration activity, etc.)? No
• Could this change impact execution of existing code? No

How should this be tested?

1. Alone the Mirador Integration Islandora app.
2. Follow the instructions to compile the Webpack output.
   2.1. $ npm install
   2.2. $ npm run web pack
   2.3 $ cp web pack/dist/main.js [drupal root]/web/libraries/mirador/dist #create if needed
3. Go to /admin/config/media/mirador, choose 'Local' in the library location setting and save.
4. Clear your cache and load a page with Mirador on it.
5. In web inspector, check the Network tab for where 'main.js' is retrieved from . It should say your local site and not GitHub.
   5.1. Alternatively, rename the local dist/main.js to something random, clear caches and reload. The Mirador viewer should no longer show up.

Documentation Status

• Does this change existing behaviour that's currently documented? No
• Does this change require new pages or sections of documentation? No
• Who does this need to be documented for? Developers
• Associated documentation pull request(s): ___ or documentation issue ___ To come.

Additional Notes:

Any additional information that you think would be helpful when reviewing this

Interested parties

Tag (@ mention) interested parties or, if unsure, @Islandora/committers

@rosiel

[alxp]

The mirador-integration-islandora app on Roblib's repository has been updated with newer Webpack dependency so it compiles again.

This PR can now be properly tested so I'm marking it as ready for review.

[rosiel]

I am still seeing GET https://roblib.github.io/mirador-integration-islandora/islandora-mirador-0.1.0.js. Perhaps my setup isn't correct. I have checked "Local library..." in Mirador settings.

[rosiel]

From debugging, it shows that in line 97 of islandora_mirador.module, setting the value of $libraries['mirador']['js']['/libraries/mirador/dist/main.js'] causes `$libraries['mirador']['js'] to have 2 values, as the old value (roblib.github.io...) isn't being deleted.