Add force-enable-realip-module

[dschwar]

What this PR does / why we need it:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Which issue/s this PR fixes

How Has This Been Tested?

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

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[ElvinEfendi]

/ok-to-test

[dschwar]

/check-cla

[ElvinEfendi]

@aledbf what do you think of the naming? The idea here is to be able to control enablement of Real IP module independent UseForwardedHeaders and Proxy Protocol. Because sometimes we need to configure Real IP module only, but not trust X-Forwarded-Host and X-Forwarded-Proto headers.

[ElvinEfendi]

@dschwar can you also add another test case that tests this new setting in combination with UseForwardedHeaders setting?

[ElvinEfendi]

@dschwar we will also need a docs adjustment once we agree on the change.

Alternative to this would be relying on https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/configmap/#proxy-real-ip-cidr to toggle the configuration of Real IP module. But that would be implicit and would introduce backward incompatibility.

[ElvinEfendi]

Given we have proxy-real-ip-cidr, let's keep the new name as close to it as possible, so let's call it enable-real-ip instead.

Also @dschwar I think it would be a lot cleaner to implement @XaF's idea about setting the value of EnableRealIp attribute base on the values of UseForwardedHeaders and UseProxyProtocol. Then in the template we can simply do if $cfg.EnableRealIp.

Once these two things are addressed we can merge this PR (you will also need to squash the commits).

[dschwar]

Also @dschwar I think it would be a lot cleaner to implement @XaF's idea about setting the value of EnableRealIp attribute base on the values of UseForwardedHeaders and UseProxyProtocol. Then in the template we can simply do if $cfg.EnableRealIp.

I played around with this and I feel like it introduces a lot of complexity and fragility to determine if we should enable realip. I'd prefer not to go with this.

We'd end up with code like

	if val, ok := conf[useForwardedHeaders]; ok {
		b, _ := strconv.ParseBool(val)
		if b {
			shouldEnableRealIp = true
		}
	}

	if val, ok := conf[useProxyProtocol]; ok {
		b, _ := strconv.ParseBool(val)
		if b {
			shouldEnableRealIp = true
		}
	}

	if val, ok := conf[enableRealIp]; ok {
		b, _ := strconv.ParseBool(val)
		if shouldEnableRealIp || b {
			delete(conf, enableRealIp)
		}
		if b {
			shouldEnableRealIp = true
		}
	}

which isn't cleaner IMO.

[dschwar]

Not sure if this is needed, @ElvinEfendi can you confirm?

[ElvinEfendi]

Yes, we want to default this to false. (It probably defaults to false when unset but better be explicit)

[ElvinEfendi]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dschwar, ElvinEfendi

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[aledbf]

/hold

[aledbf]

I will remove the hold after the 0.34.1 release

[ElvinEfendi]

I will remove the hold after the 0.34.1 release

@aledbf assuming this release is for the bug fix and will happen shortly?

[aledbf]

@aledbf assuming this release is for the bug fix and will happen shortly?

Yes

[XaF]

I played around with this and I feel like it introduces a lot of complexity and fragility to determine if we should enable realip. I'd prefer not to go with this.

I usually prefer logic in code than in templates. Code is for logic, templates not as much. Wouldn't a loop solve the readability complexity here?

enableRealIpParameters := []..{useForwardedHeaders, useProxyProtocol, enableRealIp}
shouldEnableRealIp := false
for _, parameter := range enableRealIpParameters {
  if val, ok := conf[parameter]; ok {
    b, _ := strconv.ParseBool(val)
    if b {
      shouldEnableRealIp = true
    }
  }
}

Not feeling too strongly about this though, as long as the feature is there!

[dschwar]

@aledbf it looks like 0.34.1 has been released, can we merge this?

[aledbf]

/hold cancel