chore(Endpoint): Add endpoint class and tests (#401)

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**⚙️ Type of change**

- [ ] ⚙️ Feature/App addition
- [ ] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code

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- [ ] ⚖️ My code follows the style guidelines of this project
- [ ] 👀 I have performed a self-review of my own code
- [ ] #️⃣ I have commented my code, particularly in hard-to-understand
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- [ ] 📄 I have made corresponding changes to the documentation
- [ ] ⚠️ My changes generate no new warnings
- [ ] 🧪 I have added tests to this description that prove my fix is
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**➕ App addition**

If this PR is an app addition please make sure you have done the
following.

- [ ] 🪞 I have opened a PR on
[truecharts/containers](https://github.com/truecharts/containers) adding
the container to TrueCharts mirror repo.
- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

---

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library/common-test/tests/service/external_ip_test.yaml

@@ -4,7 +4,7 @@ templates:
 chart:
   appVersion: &appVer v9.9.9
 tests:
-  - it: should pass with type externalIP
+  - it: should pass with type externalIP and useSlice unset (default)
     set:
       service:
         my-service:
@@ -144,13 +144,14 @@ tests:
             - addresses:
                 - 1.1.1.1
 
-  - it: should pass with type ExternalIP and https
+  - it: should pass with type ExternalIP and https and useSlice explicitly set to true
     set:
       service:
         my-service:
           enabled: true
           primary: true
           type: ExternalIP
+          useSlice: true
           externalIP: 1.1.1.1
           ports:
             port-name:
@@ -196,3 +197,124 @@ tests:
           path: metadata.annotations
           content:
             traefik.ingress.kubernetes.io/service.serversscheme: https
+
+  - it: should pass with type ExternalIP and useSlice set to false
+    set:
+      service:
+        my-service:
+          enabled: true
+          primary: true
+          type: ExternalIP
+          useSlice: false
+          externalIP: 1.1.1.1
+          ports:
+            port-name:
+              enabled: true
+              primary: true
+              port: 443
+              protocol: https
+    asserts:
+      - documentIndex: *serviceDoc
+        equal:
+          path: spec
+          value:
+            publishNotReadyAddresses: false
+            ports:
+            - name: port-name
+              port: 443
+              protocol: TCP
+              targetPort: 443
+      - documentIndex: &endpointDoc 1
+        isKind:
+          of: Endpoint
+      - documentIndex: *endpointDoc
+        isAPIVersion:
+          of: v1
+      - documentIndex: *endpointDoc
+        equal:
+          path: subsets
+          value:
+            - addresses:
+                - ip: 1.1.1.1
+              ports:
+                - name: port-name
+                  port: 443
+                  protocol: TCP
+      - documentIndex: &serviceDoc 0
+        isKind:
+          of: Service
+      - documentIndex: *serviceDoc
+        isSubset:
+          path: metadata.annotations
+          content:
+            traefik.ingress.kubernetes.io/service.serversscheme: https
+
+  - it: should pass with type ExternalIP and useSlice set to false, multiple ports
+    set:
+      service:
+        my-service:
+          enabled: true
+          primary: true
+          type: ExternalIP
+          useSlice: false
+          externalIP: 1.1.1.1
+          ports:
+            port-name:
+              enabled: true
+              primary: true
+              port: 12345
+            port-name2:
+              enabled: true
+              port: 12344
+              targetPort: 12346
+              protocol: http
+              appProtocol: http
+    asserts:
+      - documentIndex: *serviceDoc
+        equal:
+          path: spec
+          value:
+            publishNotReadyAddresses: false
+            ports:
+            - name: port-name
+              port: 12345
+              protocol: TCP
+              targetPort: 12345
+            - name: port-name2
+              port: 12344
+              protocol: TCP
+              targetPort: 12346
+      - documentIndex: &endpointDoc 1
+        isKind:
+          of: Endpoint
+      - documentIndex: *endpointDoc
+        isAPIVersion:
+          of: v1
+      - documentIndex: *endpointDoc
+        equal:
+          path: metadata.name
+          value: release-name-common-test
+      - documentIndex: *endpointDoc
+        equal:
+          path: metadata.labels
+          value:
+            app.kubernetes.io/managed-by: Helm
+            app.kubernetes.io/version: *appVer
+            helm.sh/chart: common-test-1.0.0
+            helm-revision: "0"
+            app: common-test-1.0.0
+            release: RELEASE-NAME
+      - documentIndex: *endpointDoc
+        equal:
+          path: subsets
+          value:
+            - addresses:
+                - ip: 1.1.1.1
+              ports:
+                - name: port-name
+                  port: 12345
+                  protocol: TCP
+                - name: port-name2
+                  port: 12346
+                  protocol: TCP
+                  appProtocol: http

library/common/Chart.yaml

@@ -15,4 +15,4 @@ maintainers:
 name: common
 sources: null
 type: library
-version: 12.4.24
+version: 12.5.0

library/common/templates/class/_endpoint.tpl

@@ -0,0 +1,32 @@
+{{/* Endpoint Class */}}
+{{/* Call this template:
+{{ include "tc.v1.common.class.endpoint" (dict "rootCtx" $ "objectData" $objectData) }}
+
+rootCtx: The root context of the chart.
+objectData: The service data, that will be used to render the Service object.
+*/}}
+
+{{- define "tc.v1.common.class.endpoint" -}}
+  {{- $rootCtx := .rootCtx -}}
+  {{- $objectData := .objectData }}
+---
+apiVersion: v1
+kind: Endpoint
+metadata:
+  name: {{ $objectData.name }}
+  {{- $labels := (mustMerge ($objectData.labels | default dict) (include "tc.v1.common.lib.metadata.allLabels" $rootCtx | fromYaml)) -}}
+  {{- with (include "tc.v1.common.lib.metadata.render" (dict "rootCtx" $rootCtx "labels" $labels) | trim) }}
+  labels:
+    {{- . | nindent 4 }}
+  {{- end -}}
+  {{- $annotations := (mustMerge ($objectData.annotations | default dict) (include "tc.v1.common.lib.metadata.allAnnotations" $rootCtx | fromYaml)) -}}
+  {{- with (include "tc.v1.common.lib.metadata.render" (dict "rootCtx" $rootCtx "annotations" $annotations) | trim) }}
+  annotations:
+    {{- . | nindent 4 }}
+  {{- end }}
+subsets:
+  - addresses:
+      {{- include "tc.v1.common.lib.endpoint.addresses" (dict "rootCtx" $rootCtx "objectData" $objectData) | trim | nindent 6 }}
+    ports:
+      {{- include "tc.v1.common.lib.endpoint.ports" (dict "rootCtx" $rootCtx "objectData" $objectData) | trim | nindent 6 }}
+{{- end -}}

library/common/templates/class/_service.tpl

@@ -100,6 +100,15 @@ spec:
     {{- end }}
   {{- end -}}
   {{- if eq $objectData.type "ExternalIP" -}}
-    {{- include "tc.v1.common.class.endpointSlice" (dict "rootCtx" $rootCtx "objectData" $objectData) | trim | nindent 0 }}
+    {{- $useSlice := true -}}
+    {{- if kindIs "bool" $objectData.useSlice -}}
+      {{- $useSlice = $objectData.useSlice -}}
+    {{- end -}}
+
+    {{- if $useSlice -}}
+      {{- include "tc.v1.common.class.endpointSlice" (dict "rootCtx" $rootCtx "objectData" $objectData) | trim | nindent 0 }}
+    {{- else -}}
+      {{- include "tc.v1.common.class.endpoint" (dict "rootCtx" $rootCtx "objectData" $objectData) | trim | nindent 0 }}
+    {{- end -}}
   {{- end -}}
 {{- end -}}

library/common/templates/lib/endpoint/_addresses.tpl

@@ -0,0 +1,20 @@
+{{/* Endpoint - addresses */}}
+{{/* Call this template:
+{{ include "tc.v1.common.lib.endpoint.addresses" (dict "rootCtx" $rootCtx "objectData" $objectData) -}}
+rootCtx: The root context of the chart.
+objectData: The object data of the service
+*/}}
+
+{{- define "tc.v1.common.lib.endpoint.addresses" -}}
+  {{- $rootCtx := .rootCtx -}}
+  {{- $objectData := .objectData -}}
+
+  {{- if not $objectData.externalIP -}}
+    {{- fail "EndpointSlice - Expected non-empty <externalIP>" -}}
+  {{- end -}}
+
+  {{- if not (kindIs "string" $objectData.externalIP) -}} {{/* Only single IP is supported currently on this lib */}}
+    {{- fail (printf "EndpointSlice - Expected <externalIP> to be a [string], but got [%s]" (kindOf $objectData.externalIP)) -}}
+  {{- end }}
+  - ip: {{ tpl $objectData.externalIP $rootCtx }}
+{{- end -}}

library/common/templates/lib/endpoint/_ports.tpl

@@ -0,0 +1,40 @@
+{{/* Endpoint - Ports */}}
+{{/* Call this template:
+{{ include "tc.v1.common.lib.endpoint.ports" (dict "rootCtx" $rootCtx "objectData" $objectData) -}}
+rootCtx: The root context of the chart.
+objectData: The object data of the service
+*/}}
+
+{{- define "tc.v1.common.lib.endpoint.ports" -}}
+  {{- $rootCtx := .rootCtx -}}
+  {{- $objectData := .objectData -}}
+
+  {{- $tcpProtocols := (list "tcp" "http" "https") -}}
+  {{- range $name, $portValues := $objectData.ports -}}
+    {{- if $portValues.enabled -}}
+      {{- $protocol := $rootCtx.Values.fallbackDefaults.serviceProtocol -}} {{/* Default to fallback protocol, if no protocol is defined */}}
+      {{- $port := $portValues.targetPort | default $portValues.port -}}
+
+      {{/* Expand targetPort */}}
+      {{- if (kindIs "string" $port) -}}
+        {{- $port = (tpl $port $rootCtx) -}}
+      {{- end -}}
+      {{- $port = int $port -}}
+
+      {{- with $portValues.protocol -}}
+        {{- $protocol = tpl . $rootCtx -}}
+
+        {{- if mustHas $protocol $tcpProtocols -}}
+          {{- $protocol = "tcp" -}}
+        {{- end -}}
+      {{- end }}
+- name: {{ $name }}
+  port: {{ $port }}
+  protocol: {{ $protocol | upper }}
+      {{- with $portValues.appProtocol }}
+  appProtocol: {{ tpl . $rootCtx | lower }}
+      {{- end -}}
+    {{- end -}}
+  {{- end -}}
+
+{{- end -}}