frontend: Use net.JoinHostPort to support IPv6 addresses

[matthewpi]

What this PR does / why we need it:

Fixes an issue when using IPv6 where IPv6 addresses are not properly joined with ports resulting in the ring attempting to incorrectly use ::1:7946 instead of the proper [::1]:7946 notation.

With this change it's fully possible to use Loki within an IPv6 only network.

This PR also changes a few other areas that incorrectly join ports. But the main area where people are likely to run into this issue is with the frontend and worker service, hence the title and changelog entry referring to those only.

Which issue(s) this PR fixes:
Fixes #10532 (issue was closed with a workaround that shouldn't be required)

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• CHANGELOG.md updated
  • If the change is worth mentioning in the release notes, add add-to-release-notes label
• Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
• For Helm chart changes bump the Helm chart version in production/helm/loki/Chart.yaml and update production/helm/loki/CHANGELOG.md and production/helm/loki/README.md. Example PR

---

For those interested in trying this out, here is a shortened snippet of the configuration changes I needed to make in order to get IPv6 working.

common:
  ring:
    instance_enable_ipv6: true
compactor:
  compactor_ring:
    instance_enable_ipv6: true
distributor:
  ring:
    instance_enable_ipv6: true
memberlist:
  bind_addr:
    - '::'
  bind_port: 7946
  cluster_label: loki
  randomize_node_name: false
ingester:
  lifecycler:
    enable_inet6: true
query_scheduler:
  scheduler_ring:
    instance_enable_ipv6: true
ruler:
  ring:
    instance_enable_ipv6: true
index_gateway:
  ring:
    instance_enable_ipv6: true

[CLAassistant]

All committers have signed the CLA.

[github-actions]

Trivy scan found the following vulnerabilities:

• HIGH, Target: docker.io/grafana/loki:main-cd74ddf (alpine 3.18.4), Type: alpine openssl: Incorrect cipher key and IV length processing in libcrypto3 v3.1.3-r0. Fixed in v3.1.4-r0
• HIGH, Target: docker.io/grafana/loki:main-cd74ddf (alpine 3.18.4), Type: alpine openssl: Incorrect cipher key and IV length processing in libssl3 v3.1.3-r0. Fixed in v3.1.4-r0
  \nTo see more details on these vulnerabilities, and how/where to fix them, please run docker build -t grafana/loki:main-cd74ddf -f cmd/loki/Dockerfile .
  trivy i grafana/loki:main-cd74ddf on your branch. If these were not introduced by your PR, please considering fixing them in via a subsequent PR. Thanks!

[periklis]

I thought I got everything the last time I fixed IPv6 support with #11121. Thanks a lot!

[matthewpi]

I thought I got everything the last time I fixed IPv6 support with #11121. Thanks a lot!

I believe you did get all the one's for the rings, but this one is for the front-ends. I should probably update the title and description for this PR to more accurately match that.

[dbazhal]

Hey guys!
Would be great to continue moving this. Can I help somehow? I could test it in my environment if that would help.

[grafanabot]

Hello @periklis!
Backport pull requests need to be either:

• Pull requests which address bugs,
• Urgent fixes which need product approval, in order to get merged,
• Docs changes.

Please, if the current pull request addresses a bug fix, label it with the type/bug label.
If it already has the product approval, please add the product-approved label. For docs changes, please add the type/docs label.
If the pull request modifies CI behaviour, please add the type/ci label.
If none of the above applies, please consider removing the backport label and target the next major/minor release.
Thanks!

[grafanabot]

The backport to release-2.9.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new branch
git switch --create backport-10650-to-release-2.9.x origin/release-2.9.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x a91f3f11b3bf15d559b7b9206fc7c2791ca71fdc

When the conflicts are resolved, stage and commit the changes:

git add . && git cherry-pick --continue

If you have the GitHub CLI installed:

# Push the branch to GitHub:
git push --set-upstream origin backport-10650-to-release-2.9.x
# Create the PR body template
PR_BODY=$(gh pr view 10650 --json body --template 'Backport a91f3f11b3bf15d559b7b9206fc7c2791ca71fdc from #10650{{ "\n\n---\n\n" }}{{ index . "body" }}')
# Create the PR on GitHub
echo "${PR_BODY}" | gh pr create --title "[release-2.9.x] frontend: Use `net.JoinHostPort` to support IPv6 addresses" --body-file - --label "size/S" --label "type/bug" --label "backport" --base release-2.9.x --milestone release-2.9.x --web

Or, if you don't have the GitHub CLI installed (we recommend you install it!):

# Push the branch to GitHub:
git push --set-upstream origin backport-10650-to-release-2.9.x

# Create a pull request where the `base` branch is `release-2.9.x` and the `compare`/`head` branch is `backport-10650-to-release-2.9.x`.

# Remove the local backport branch
git switch main
git branch -D backport-10650-to-release-2.9.x