[Fleet] Integrations UI not loading when EPR is inaccessible

[juliaElastic]

Integrations UI not loading when EPR is inaccessible
Version: 8.3

Seems to be a regression since this was working since 8.0 #115564

Steps to reproduce:

• Set EPR to a dummy value in kibana.yml, e.g. xpack.fleet.registryUrl: http://localhost:12345
• Visit Integrations app
• Result: Installed integrations are not loading, neither Browse or Installed tabs, fails with 502 after 2 minutes.
• Expected: Page should load with a callout, installed integrations should show installed cards.

[elasticmachine]

Pinging @elastic/fleet (Team:Fleet)

[juliaElastic]

After further investigation, I found that the callout is visible and the epr call times out after 30s when I make EPR inaccessible by editing the /etc/hosts file as it was tested here.

So it is not a regression per se, but a different way of setting an inaccessible epr.

[juliaElastic]

I don't know what happened, but I can't reproduce this now. I see the callout coming up after 30s in both ECE and local.

I think the 2 min timeout was coming when all network access was blocked, not only EPR.
EDIT: Yes, I tested again with the whole network blocked, and I got the 2 min timeout. The callout is still visible, so that is working fine. I think I got confused because I took a screenshot of the Installed tab, which doesn't show the callout.

The installed packages are not showing the installed bundled packages though, I think that is expected based on this discussion #74614 (comment)

with epr inaccessible:

{"statusCode":502,"error":"Bad Gateway","message":"Error connecting to package registry: request to http://localhost:12345/categories?experimental=true&include_policy_templates=true&kibana.version=8.4.0 failed, reason: connect ECONNREFUSED 127.0.0.1:12345"}

with no internet access:

{"ok":false,"message":"backend closed connection"}