MINOR: haproxy: add support for loadBalancerClass

The Service template rendered loadBalancerIP and loadBalancerSourceRanges but
had no way to select a non-default load balancer implementation, leaving this
the only chart in the repo without loadBalancerClass after 1.2.0 added it to
haproxy-unified-gateway.

Unlike the other two charts, this one declares kubeVersion ">=1.17.0-0", which
predates the field entirely (added in Kubernetes 1.21, GA in 1.24). Gate it
behind semverCompare ">=1.21.0-0", matching how the same template already gates
trafficDistribution behind 1.31, and additionally on type=LoadBalancer since the
API server forbids loadBalancerClass on any other Service type.

No ci/ values file: `ct install` and integration-test.sh use `helm install
--wait`, which blocks until a LoadBalancer Service reports
status.loadBalancer.ingress, and this chart is not in LB_CHARTS in
.github/scripts/install_charts.sh so cloud-provider-kind is not running. The
test_loadbalancer_fields checks in test/local-test.sh pick this chart up
automatically now that values.yaml carries the key.

Also fix the absence assertion in that helper to use [[:space:]] instead of the
GNU-only \s, which BSD grep does not support in ERE; on macOS the check could
never match and so always passed.

Chart version 1.29.0 -> 1.30.0.

Signed-off-by: Dinko Korunic <dkorunic@haproxy.com>

Author: dkorunic

haproxy/Chart.yaml

@@ -16,7 +16,7 @@ apiVersion: v2
 name: haproxy
 description: A Helm chart for HAProxy on Kubernetes
 type: application
-version: 1.29.0
+version: 1.30.0
 appVersion: 3.3.10
 kubeVersion: ">=1.17.0-0"
 keywords:
@@ -39,3 +39,4 @@ annotations:
       url: https://github.com/haproxytech/helm-charts/issues
   artifacthub.io/changes: |
     - Update base image to HAProxy 3.3.10
+    - Add support for loadBalancerClass

haproxy/README.md

@@ -135,6 +135,21 @@ helm install my-haproxy4 haproxytech/haproxy \
 
 **_NOTE_**: With helm `--set` it is needed to put quotes and escape dots in the annotation key and commas in the value string.
 
+### Selecting a LoadBalancer implementation
+
+When more than one load balancer controller runs in a cluster, `service.loadBalancerClass` picks which one reconciles the Service. Leaving it unset uses the cluster's default implementation:
+
+```console
+helm install my-haproxy5 haproxytech/haproxy \
+  --set service.type=LoadBalancer \
+  --set service.loadBalancerClass="example.com/internal-lb" \
+  --set service.loadBalancerSourceRanges[0]="192.0.2.0/24"
+```
+
+**_NOTE_**: `loadBalancerClass` renders only when `service.type` is `LoadBalancer` and the cluster is Kubernetes 1.21 or newer (the field is GA as of 1.24). On older clusters it is omitted.
+
+**_NOTE_**: `loadBalancerClass` is immutable while the Service stays type `LoadBalancer`. Kubernetes rejects a change on an existing Service, so `helm upgrade` cannot alter it in place - the Service has to be recreated.
+
 ### Using values from YAML file
 
 As opposed to using many `--set` invocations, much simpler approach is to define value overrides in a separate YAML file and specify them when invoking Helm.

haproxy/templates/service.yaml

@@ -51,6 +51,11 @@ spec:
   loadBalancerSourceRanges:
   {{- toYaml . | nindent 2 }}
   {{- end }}
+  {{- /* loadBalancerClass exists from Kubernetes 1.21 (GA 1.24) and the API
+         server forbids it unless type is LoadBalancer, so gate on both. */}}
+  {{- if and (semverCompare ">=1.21.0-0" .Capabilities.KubeVersion.Version) (eq .Values.service.type "LoadBalancer") .Values.service.loadBalancerClass }}
+  loadBalancerClass: {{ .Values.service.loadBalancerClass | quote }}
+  {{- end }}
   {{- if .Values.service.ipFamilies }}
   ipFamilies:
   {{- toYaml .Values.service.ipFamilies | nindent 2 }}

haproxy/values.yaml

@@ -506,6 +506,12 @@ service:
   # ref: https://kubernetes.io/docs/tasks/access-application-cluster/configure-cloud-provider-firewall/
   loadBalancerSourceRanges: []
 
+  ## Class of load balancer implementation, rendered only when type is
+  ## LoadBalancer and Kubernetes is >= 1.21 (GA in 1.24). Immutable while the
+  ## Service stays type LoadBalancer, so helm upgrade cannot change it in place
+  # ref: https://kubernetes.io/docs/concepts/services-networking/service/#load-balancer-class
+  loadBalancerClass: null
+
   ## Service ExternalIPs
   # ref: https://kubernetes.io/docs/concepts/services-networking/service/#external-ips
   externalIPs: []

test/local-test.sh

@@ -467,7 +467,7 @@ test_loadbalancer_fields() {
     local label="$chart: LoadBalancer fields absent with default Service type"
     local output
     output=$(helm template test-release "$REPO_ROOT/$chart" 2>&1)
-    if echo "$output" | grep -qE '^\s+loadBalancer(IP|Class|SourceRanges):'; then
+    if echo "$output" | grep -qE '^[[:space:]]+loadBalancer(IP|Class|SourceRanges):'; then
         log_fail "$label"
     else
         log_pass "$label"