[Heartbeat] Check certificates for Browser based Synthetic monitors (step 1 main URL)

[paulb-elastic]

Existing TLS certificate checks for Heartbeat monitors are useful to give an early warning that certificates are going to expire (and give users the time to renew them before they expire which may well impact the availability of the site).

These are not currently available for browser based Synthetics monitors, but the requirement and value that certificate checks provides, is just as valuable for these monitors (arguably more so as more hosts and content are included in browser monitors, with a wider number of hosts needed to deliver it to make up the website).

Use case

• As a Synthetic browser based monitoring customer
• I want to check the status of TLS certificate for the root URL tested with Synthetics (the same as it does for HTTP checks)
• So I get visibility and early warning that the main host has an expiring certificate

This requirement is being split into two phases.

Phase 1 certificate check the host of the main URL on step 1 (this issue)

Feature:

• Check the certificate status for the host defined in the URL for the user journey (as shown in the Url column of the Monitors Overview page (if this is accessed via HTTPS)
• Show the certificate details in the TLS Certificate column on the Monitors Overview page
• The certificate details will also be shown on the Certificates status page, the same as other Heartbeat certificate checks

In this example:

• www.elastic.co would be checked and appear in the TLS Certificate column
• www.mydomain.com would not be checked (not HTTPS) so nothing would be shown in the TLS Certificate column

Phase 2: a future enhancement to check the certificates of all hosts for a user journey monitor is detailed in this issue.