Injected proxy variables into endpoint elasticsearch does not include NO_PROXY variable

[janniten]

Hello,
We did an upgrade from 8.14.2 to 8.16.1.
In our environment the agent has the HTTP_PROXY, HTTPS-PROXY and NO_PROXY configured.
NO_PROXY variable is not being injected into endpoint .
As a result, the elastic endpoint is trying to connect the ES cluster Via proxy, which is not correct.

Thank you

• Version: 8.16.1
• Operating System: Windows / linux
• Discuss Forum URL: https://elasticstack.slack.com/archives/C02J2JBS0FP/p1733218957317399
• Steps to Reproduce: Upgrade from 8.14.2 to 8.16.1

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[michel-laterman]

HTTP_PROXY/HTTPS_PROXY injection was added with: #5044
We'll probably need to alter the injectProxyURL func to add NO_PROXY.

@intxgo, would the expected value in the config be no_proxy: string, or no_proxy: []string?

[intxgo]

Since the env vars are injected as a regular output proxy settings, there's no place for NO_PROXY (endpoint won't recognize it, ignore it). However since the output URL is known, I think the NO_PROXY can be matched against the output URL at Agent side before deciding to inject HTTP_PROXY/HTTPS_PROXY variable to the output config.

[intxgo]

Alternative solution would be to pass all three HTTP_PROXY, HTTPS_PROXY, NO_PROXY to Endpoint as Agent env variables, a new structure in the config message instead of injecting them to the output configuration. We will need to handle this on Endpoint side too, but in general Endpoint proxy table already has place for storing Agent env variables.