Upstream grpc gem only supports http scheme for proxy servers

Summary

This issue is the result of a customer ticket ZD-667687 (Internal).

They are trying to activate their instance and the communication to customers.gitlab.com is being blocked due to the following error from puma (which is happening a lot more than just for this request):

'https' scheme not supported in proxy URI

and this in the exceptions_json.log in direct relation to the activation

{
 "severity": "ERROR",
 "time": "2025-11-03T16:08:07.120Z",
 "correlation_id": "<correlation-id>",
 "meta.caller_id": "GraphqlController#execute",
 "meta.feature_category": "plan_provisioning",
 "meta.organization_id": 1,
 "meta.remote_ip": "<ip-address>",
 "meta.user": "<user>",
 "meta.user_id": 1,
 "meta.client_id": "user/1",
 "exception.class": "Errno::ECONNRESET",
 "exception.message": "Connection reset by peer",

Steps to reproduce

  • Configure a HTTPS enabled proxy
  • Configure the CA as required
  • Configure puma to use the proxy
gitlab_rails['env'] = {
  "http_proxy" => "https://<SCRUBBED>",
  "https_proxy" => "https://<SCRUBBED>",
  "HTTP_PROXY" => "https://<SCRUBBED>",
  "HTTPS_PROXY" => "https://<SCRUBBED>"
}

This error is due to a lack of support upstream in the gem we use for GRPC

https://github.com/grpc/grpc/blob/master/src/core/handshaker/http_connect/http_proxy_mapper.cc#L131-L133

  if (uri->scheme() != "http") {
    LOG(ERROR) << "'" << uri->scheme() << "' scheme not supported in proxy URI";
    return std::nullopt;
  }

however I'm unsure if we can work around this, or provide a patch?

Example Project

n/a

What is the current bug behavior?

GitLab is unable to connect through a HTTPS proxy

What is the expected correct behavior?

GitLab should be able to connect through a HTTPS proxy

Relevant logs and/or screenshots

See above

Output of checks

Results of GitLab environment info

Expand for output related to GitLab environment info 

(For installations with omnibus-gitlab package run and paste the output of:
`sudo gitlab-rake gitlab:env:info`)

(For installations from source run and paste the output of:
`sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production`)

Results of GitLab application Check

Expand for output related to the GitLab application check 
(For installations with omnibus-gitlab package run and paste the output of:
sudo gitlab-rake gitlab:check SANITIZE=true)


(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)


(we will only investigate if the tests are passing)

Possible fixes

Patch release information for backports

If the bug fix needs to be backported in a patch release to a version under the maintenance policy, please follow the steps on the patch release runbook for GitLab engineers.

Refer to the internal "Release Information" dashboard for information about the next patch release, including the targeted versions, expected release date, and current status.

High-severity bug remediation

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Edited by 🤖 GitLab Bot 🤖