fix: IPv6 issues for nginx

[qdrddr]

PR fulfills these requirements

• Commit message(s) and PR title follows the format [fix|feat|ci|chore|doc]: TICKET-ID: Short description of change made ex. fix: DEV-XXXX: Removed inconsistent code usage causing intermittent errors
• Tests for the changes have been added/updated (for bug fixes/features)
• Docs have been added/updated (for bug fixes/features)
• Best efforts were made to ensure docs/code are concise and coherent (checked for spelling/grammatical errors, commented out code, debug logs etc.)
• Self-reviewed and ran all changes on a local instance (for bug fixes/features)

Change has impacts in these area(s)

(check all that apply)

• Product design
• Backend (Database)
• Backend (API)
• Frontend

Describe the reason for change

(link to issue, supportive screenshots etc.)
Bug with processing IPv6
#7081

What does this fix?

(if this is a bug fix)
Correctly processes IPv6

What is the new behavior?

(if this is a breaking or feature change)
Be able to run in k8s environments with IPv6

What is the current behavior?

(if this is a breaking or feature change)
Nginx container fails due to the bug

What libraries were added/updated?

(list all with version changes)
N/A

Does this change affect performance?

(if so describe the impacts positive or negative)
No

Does this change affect security?

(if so describe the impacts positive or negative)
No

What alternative approaches were there?

(briefly list any if applicable)

What feature flags were used to cover this change?

(briefly list any if applicable)

Does this PR introduce a breaking change?

(check only one)

• Yes, and covered entirely by feature flag(s)
• Yes, and covered partially by feature flag(s)
• [ x] No
• Not sure (briefly explain the situation below)

What level of testing was included in the change?

(check all that apply)

• e2e
• integration
• unit

Which logical domain(s) does this change affect?

(for bug fixes/features, be as precise as possible. ex. Authentication, Annotation History, Review Stream etc.)
Proxy for thee main app

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[farioas]

Did you test this out? I have no k8s cluster with ipv6 to check :)

[qdrddr]

Yes, I have tested @farioas

Here is how the /etc/resolv.conf looks like when you have both IPv4 & IPv6 nameservers in the DualStack k8s environment:

cat /etc/resolv.conf
search ai-system.svc.cluster.local svc.cluster.local cluster.local
nameserver 10.43.0.10
nameserver 2001:cafe:42:1::a
options ndots:5

After I process this file with this new code:

nameservers=$(awk '$1=="nameserver" {
    ns = $2;
    # Capture only IPv6 addresses (they contain a colon and no dot)
    if (ns ~ /^[0-9a-fA-F:]+$/ && ns ~ /:/ && ns !~ /\./) {
        printf "[%s] ", ns;
    } else {
        # IPv4 addresses
        printf "%s ", ns;
    }
}' /etc/resolv.conf)
echo "resolver $nameservers;" > $OPT_DIR/nginx/resolv.conf

Here is how the resulting $OPT_DIR/nginx/resolv.conf file would look like

resolver 10.43.0.10 [2001:cafe:42:1::a] ;

It looks correct to me.

[qdrddr]

Which version of the packaged docker container is this fix expected to be implemented?

[farioas]

It's available in docker image tag: 20250214.164321-develop-cbf53fdac