[Upgrade Assistant] Redesign overview page

[alisonelizabeth]

This PR implements the first phase of the Upgrade Assistant redesign: a new Overview page and the start to distinguish between Elasticsearch and other stack (i.e., Kibana) deprecations.

Other notable changes:

• Client-side routing
• Breadcrumbs
• Changed the behavior of the "level" filter buttons for ES deprecations. Instead of filtering by "all" or "critical", we now display all deprecations by default and the user can toggle the filters on and off for "critical" and "warning".

What's next

• After this PR is merged, I will open up a subsequent PR to incorporate Kibana deprecations (I felt the changes were too large to include here). The UX will be updated to look something like this:

• I have not changed the UX for the list of ES deprecations or reindexing flow. This will addressed in a separate PR.
• We've discussed enhancing the overview page by including a "highlights" section that showcases new features in 8.0. This will come as I gain more information on the type of content we wish to show here.

How to test/review

Note for 7.13, users will still see the "coming soon" prompt. In order to test these changes, you will need to disable that functionality. In x-pack/plugins/upgrade_assistant/common/constants.ts, set UA_READONLY_MODE to false.

You can add some mock deprecation data by modifying the response returned from getUpgradeAssistantStatus() in x-pack/plugins/upgrade_assistant/server/lib/es_migration_apis.ts. I've created a gist with some mock data: https://gist.github.com/alisonelizabeth/f093c1464ffd90f9781c42399c758ab4.

• General design feedback (with the understanding that this is the first iteration 😄)
• Verify deprecation logging toggle
• Verify routing/breadcrumbs
• Verify "level" filter functionality on ES deprecations page
• Verify no regressions in ES deprecations list (i.e., search still works, toggle accordions, etc.)

Screenshots

// Note: This warning callout was pre-existing. It may or may not be applicable anymore depending on which release we decide to re-enable UA. I decided to leave for now.

[sebelga]

Or directly onSearchChange={setSearch} 😊

[mdefazio]

This was pre-existing behavior. I also considered changing it, but it gets a bit tricky if a user has some accordions opened and some closed - what should the toggle state be at that point? @mdefazio do you know if we have any existing patterns to follow for something like this?

@alisonelizabeth I'm not sure of a consistent pattern we have for accordions collapsing/expanding across Kibana (we should! and now have it on our "Needs guidelines" list). I'm inclined to say keep the existing behavior. While more clunky, 2 separate buttons is quite obvious. So we can absolutely streamline this, but I'd like to see if we can get some collective thoughts (hopefully quickly) around this that we can apply everywhere.

[debadair]

Does the reference to "steps" here still make sense?

[alisonelizabeth]

Good point. I changed this to: Check the Overview page for other Stack deprecations. Happy to make any additional changes!

[debadair]

This reads like Kibana has a version of Elasticsearch.

Suggested change

	'One or more Elasticsearch nodes have a newer version of Elasticsearch than Kibana.',
	'Upgrade Kibana to the same version as your Elasticsearch cluster. One or more nodes in the cluster is running <version xyz> .',

[alisonelizabeth]

We currently don't have access to the version in this context. It's something we can support, but I think I'd prefer to do so in a separate PR. For now, I've updated this to:

Upgrade Kibana to the same version as your Elasticsearch cluster. One or more nodes in the cluster is running a different version than Kibana.

[alisonelizabeth]

Thanks for the copy review @debadair! I applied your suggestions and responded to your comment about the message mentioning "steps" on the overview page.

[alisonelizabeth]

@elasticmachine merge upstream

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 95b7e18
• Storybooks Preview
• Documentation Changes

Metrics [docs]

Module Count

Fewer modules leads to a faster build time

id	before	after	diff
upgradeAssistant	70	72	+2

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
upgradeAssistant	117.9KB	119.5KB	+1.6KB

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
core	379.7KB	379.9KB	+173.0B
upgradeAssistant	29.9KB	30.2KB	+312.0B
total			+485.0B

History

• 💔 Build #119588 failed 2bca115
• 💔 Build #119485 failed f33f353
• 💔 Build #119481 failed 1accb03
• 💔 Build #119484 failed 7b5817d
• 💚 Build #119202 succeeded 797acc4

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

[alisonelizabeth]

I'm going to go ahead and merge this PR. I'm going to leave the deprecation toggle as-is for now, as the UX will likely change again once we support deprecation log indexing (#79208).