Improve hosts search field (regex for used by email)

[marko-lisica]

Goal

User story
As a IT admin,
I want to search hosts by typing email partially
so that I can easily find a host based on human-host mapping information.

Changes

Requirements

• User should be able to search by email (device_mapping) without having to type full email (e.g. If the user searches for mark Fleet should list hosts that have email marko@example.com)

Product

• [ ] UI changes: Change tooltip copy (as on the image below)
• [ ] Docs changes: TODO change docs

Engineering

• Requires changing how we detect if a search could be an email address, which was done for performance reasons to avoid joining with host_emails unless necessary.

• We should plan load testing the new search to see if the impact is acceptable at scale for non-email searches.

• We have a special-case in place to do an additional search when non-ASCII is used (to account for unicode chars equivalence, IIRC it was mostly for things like apostrophes), but now we would do it even if it includes the email search (since we wouldn't detect the search as being "email-like")

• This also affects ListHosts, CountHosts, ListHostsInLabel and CountHostsInLabel (which I think is required so that the exact same criteria can be used for those). To keep in mind when load testing performance.

• [ ] Database schema migrations: TODO

ℹ️  Please read this issue carefully and understand it. Pay special attention to UI wireframes, especially "dev notes".

Context

• Requestor(s): _____

QA

Risk assessment

• Requires load testing: TODO
• Risk level: Low / High TODO
• Risk description: TODO

Manual testing steps

1. Step 1
2. Step 2
3. Step 3

Testing notes

Confirmation

1. [ ] Engineer (@____): Added comment to user story confirming succesful completion of QA.
2. [ ] QA (@____): Added comment to user story confirming succesful completion of QA.

[noahtalerman]

Heads up @marko-lisica this request was discussed during feature fest last week and didn't make it into the current design sprint.

[noahtalerman]

Hey @pintomi1989 heads up, this story was prioritized during feature fest.

Aiming to ship an improvement in the next 6 weeks.

[georgekarrv]

Hey team! Please add your planning poker estimate with Zenhub @dantecatalfamo @ghernandez345 @gillespi314 @jahzielv @mna @roperzh