feat(common): add nginx ingress integration (#34469)

**Description**
As discussed we wanted to make setting-up nginx easier for users,
primarily themepark and auth/
This provides an integration to do so.

⚒️ Fixes  #33988

**⚙️ Type of change**

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

**🧪 How Has This Been Tested?**
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Please describe the tests that you ran to verify your changes. Provide
instructions so we can reproduce. Please also list any relevant details
for your test configuration
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**📃 Notes:**
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**✔️ Checklist:**

- [ ] ⚖️ 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
areas
- [ ] 📄 I have made changes to the documentation
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
- [ ] ⬆️ I increased versions for any altered app according to semantic
versioning
- [ ] I made sure the title starts with `feat(chart-name):`,
`fix(chart-name):`, `chore(chart-name):`, `docs(chart-name):` or
`fix(docs):`

**➕ App addition**

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

- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

---

_Please don't blindly check all the boxes. Read them and only check
those that apply.
Those checkboxes are there for the reviewer to see what is this all
about and
the status of this PR with a quick glance._

---------

Signed-off-by: Kjeld Schouten <info@kjeldschouten.nl>
Co-authored-by: Stavros Kois <s.kois@outlook.com>

charts/library/common-test/tests/ingress/nginx_test.yaml

@@ -0,0 +1,252 @@
+suite: ingress - nginx metadata test
+templates:
+  - common.yaml
+chart:
+  appVersion: &appVer v9.9.9
+release:
+  name: test-release-name
+  namespace: test-release-namespace
+tests:
+  - it: should pass with ingress created with ipWhiteList annotations from nginx
+    set:
+      service: &service
+        my-service:
+          enabled: true
+          primary: true
+          ports:
+            main:
+              enabled: true
+              primary: true
+              port: 80
+      ingress:
+        my-ingress:
+          enabled: true
+          primary: true
+          hosts: &hosts
+            - host: test-host
+              paths:
+                - path: /test-path
+          integrations:
+            nginx:
+              enabled: true
+              ipWhitelist:
+                - 10.0.0.0/8
+                - 192.168.0.0/16
+    asserts:
+      - documentIndex: &ingressDoc 1
+        isKind:
+          of: Ingress
+      - documentIndex: *ingressDoc
+        equal:
+          path: metadata.name
+          value: test-release-name-common-test
+      - documentIndex: *ingressDoc
+        isSubset:
+          path: metadata.annotations
+          content:
+            nginx.ingress.kubernetes.io/whitelist-source-range: 10.0.0.0/8,192.168.0.0/16
+
+  - it: should pass with ingress created with themePark annotations from nginx
+    set:
+      service: *service
+      ingress:
+        my-ingress:
+          enabled: true
+          primary: true
+          hosts: *hosts
+          integrations:
+            nginx:
+              enabled: true
+              themePark:
+                enabled: true
+                css: https://example.com/theme.css
+    asserts:
+      - documentIndex: &ingressDoc 1
+        isKind:
+          of: Ingress
+      - documentIndex: *ingressDoc
+        equal:
+          path: metadata.name
+          value: test-release-name-common-test
+      - documentIndex: *ingressDoc
+        isSubset:
+          path: metadata.annotations
+          content:
+            nginx.ingress.kubernetes.io/configuration-snippet: |-
+              proxy_set_header Accept-Encoding "";
+              sub_filter
+              '</head>'
+              '<link rel="stylesheet" type="text/css" href="https://example.com/theme.css">
+              </head>';
+              sub_filter_once on;
+
+  - it: should pass with ingress created with authentik annotations from nginx
+    set:
+      service: *service
+      ingress:
+        my-ingress:
+          enabled: true
+          primary: true
+          hosts: *hosts
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: authentik
+                internalHost: internal.host
+                externalHost: external.host
+    asserts:
+      - documentIndex: &ingressDoc 1
+        isKind:
+          of: Ingress
+      - documentIndex: *ingressDoc
+        equal:
+          path: metadata.name
+          value: test-release-name-common-test
+      - documentIndex: *ingressDoc
+        isSubset:
+          path: metadata.annotations
+          content:
+            nginx.ingress.kubernetes.io/auth-method: GET
+            nginx.ingress.kubernetes.io/auth-response-headers: Set-Cookie,X-authentik-username,X-authentik-groups,X-authentik-entitlements,X-authentik-email,X-authentik-name,X-authentik-uid
+            nginx.ingress.kubernetes.io/auth-signin: https://external.host/outpost.goauthentik.io/start?rd=$scheme://$http_host$escaped_request_uri
+            nginx.ingress.kubernetes.io/auth-snippet: proxy_set_header X-Forwarded-Host $http_host;
+            nginx.ingress.kubernetes.io/auth-url: http://internal.host/outpost.goauthentik.io/auth/nginx
+            nginx.ingress.kubernetes.io/backend-protocol: HTTPS
+            nginx.ingress.kubernetes.io/force-ssl-redirect: "true"
+
+  - it: should pass with ingress created with authelia annotations from nginx
+    set:
+      service: *service
+      ingress:
+        my-ingress:
+          enabled: true
+          primary: true
+          hosts: *hosts
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: authelia
+                internalHost: internal.host
+                externalHost: external.host
+    asserts:
+      - documentIndex: &ingressDoc 1
+        isKind:
+          of: Ingress
+      - documentIndex: *ingressDoc
+        equal:
+          path: metadata.name
+          value: test-release-name-common-test
+      - documentIndex: *ingressDoc
+        isSubset:
+          path: metadata.annotations
+          content:
+            nginx.ingress.kubernetes.io/auth-method: GET
+            nginx.ingress.kubernetes.io/auth-signin: https://external.host?rm=$request_method
+            nginx.ingress.kubernetes.io/auth-url: http://internal.host/api/verify
+
+  # Failures
+
+  - it: should fail with ipWhitelist not a slice
+    set:
+      service: *service
+      ingress:
+        my-ingress1:
+          enabled: true
+          primary: true
+          integrations:
+            nginx:
+              enabled: true
+              ipWhitelist: "not a slice"
+          hosts: *hosts
+    asserts:
+      - failedTemplate:
+          errorMessage: Ingress - Expected [integrations.nginx.ipWhitelist] to be a [slice], but got [string]
+
+  - it: should fail with auth.type not a valid type
+    set:
+      service: *service
+      ingress:
+        my-ingress1:
+          enabled: true
+          primary: true
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: "invalid"
+          hosts: *hosts
+    asserts:
+      - failedTemplate:
+          errorMessage: Ingress - Expected [integrations.nginx.auth.type] to be one of [authentik, authelia], but got [invalid]
+
+  - it: should fail with auth.type set to authentik but no auth.internalHost
+    set:
+      service: *service
+      ingress:
+        my-ingress1:
+          enabled: true
+          primary: true
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: authentik
+          hosts: *hosts
+    asserts:
+      - failedTemplate:
+          errorMessage: Ingress - Expected [integrations.nginx.auth.internalHost] and [integrations.nginx.auth.externalHost] to be set
+
+  - it: should fail with auth.type set to authentik but no auth.externalHost
+    set:
+      service: *service
+      ingress:
+        my-ingress1:
+          enabled: true
+          primary: true
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: authentik
+                internalHost: internal.host
+          hosts: *hosts
+    asserts:
+      - failedTemplate:
+          errorMessage: Ingress - Expected [integrations.nginx.auth.internalHost] and [integrations.nginx.auth.externalHost] to be set
+
+  - it: should fail with auth.type set to authelia but no auth.internalHost
+    set:
+      service: *service
+      ingress:
+        my-ingress1:
+          enabled: true
+          primary: true
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: authelia
+          hosts: *hosts
+    asserts:
+      - failedTemplate:
+          errorMessage: Ingress - Expected [integrations.nginx.auth.internalHost] and [integrations.nginx.auth.externalHost] to be set
+
+  - it: should fail with auth.type set to authelia but no auth.externalHost
+    set:
+      service: *service
+      ingress:
+        my-ingress1:
+          enabled: true
+          primary: true
+          integrations:
+            nginx:
+              enabled: true
+              auth:
+                type: authelia
+                internalHost: internal.host
+          hosts: *hosts
+    asserts:
+      - failedTemplate:
+          errorMessage: Ingress - Expected [integrations.nginx.auth.internalHost] and [integrations.nginx.auth.externalHost] to be set

charts/library/common/Chart.yaml

@@ -48,4 +48,4 @@ sources:
   - https://hub.docker.com/_/
   - https://hub.docker.com/r/mikefarah/yq
 type: library
-version: 28.3.0
+version: 28.4.0

charts/library/common/templates/class/_ingress.tpl

@@ -49,6 +49,7 @@ objectData: The object data to be used to render the Ingress.
 
   {{- include "tc.v1.common.lib.ingress.integration.certManager" (dict "rootCtx" $rootCtx "objectData" $objectData) -}}
   {{- include "tc.v1.common.lib.ingress.integration.traefik" (dict "rootCtx" $rootCtx "objectData" $objectData) -}}
+  {{- include "tc.v1.common.lib.ingress.integration.nginx" (dict "rootCtx" $rootCtx "objectData" $objectData) -}}
   {{- if ne $ingressClassName "tc-stopped" -}}{{/* If is stopped, dont render homepage annotations */}}
     {{- include "tc.v1.common.lib.ingress.integration.homepage" (dict "rootCtx" $rootCtx "objectData" $objectData) -}}
   {{- end }}

charts/library/common/templates/lib/ingress/integrations/_nginx.tpl

@@ -0,0 +1,32 @@
+{{- define "tc.v1.common.lib.ingress.integration.nginx" -}}
+  {{- $objectData := .objectData -}}
+  {{- $rootCtx := .rootCtx -}}
+
+  {{- $nginx := $objectData.integrations.nginx -}}
+
+  {{- if $nginx.enabled -}}
+
+    {{/* ipWhiteList */}}
+    {{- if $nginx.ipWhitelist -}}
+      {{- include "tc.v1.common.lib.ingress.integration.nginx.ipWhitelist" (dict "objectData" $objectData "whiteList" $nginx.ipWhitelist) -}}
+    {{- end -}}
+
+    {{/* themePark */}}
+    {{- if and $nginx.themePark $nginx.themePark.enabled -}}
+      {{- include "tc.v1.common.lib.ingress.integration.nginx.themePark" (dict "objectData" $objectData "themePark" $nginx.themePark) -}}
+    {{- end -}}
+
+    {{/* Auth */}}
+    {{- $validAuthTypes := (list "authentik" "authelia") -}}
+    {{- if and $nginx.auth $nginx.auth.type -}}
+      {{- if eq $nginx.auth.type "authentik" -}}
+        {{- include "tc.v1.common.lib.ingress.integration.nginx.auth.authentik" (dict "objectData" $objectData "auth" $nginx.auth) -}}
+      {{- else if eq $nginx.auth.type "authelia" -}}
+        {{- include "tc.v1.common.lib.ingress.integration.nginx.auth.authelia" (dict "objectData" $objectData "auth" $nginx.auth) -}}
+      {{- else -}}
+        {{- fail (printf "Ingress - Expected [integrations.nginx.auth.type] to be one of [%s], but got [%s]" (join ", " $validAuthTypes) $nginx.auth.type) -}}
+      {{- end -}}
+    {{- end -}}
+
+  {{- end -}}
+{{- end -}}

charts/library/common/templates/lib/ingress/integrations/nginx/_auth.tpl

@@ -0,0 +1,54 @@
+{{- define "tc.v1.common.lib.ingress.integration.nginx.auth.authentik" -}}
+  {{- $objectData := .objectData -}}
+  {{- $auth := .auth -}}
+
+  {{- if and $auth.respondHeaders (not (kindIs "slice" $auth.responseHeaders)) -}}
+    {{- fail (printf "Ingress - Expected [integrations.nginx.auth.responseHeaders] to be a [slice], but got [%s]" (kindOf $auth.responseHeaders)) -}}
+  {{- end -}}
+
+  {{- $respHeaders := ($auth.responseHeaders | default (list
+    "Set-Cookie"
+    "X-authentik-username"
+    "X-authentik-groups"
+    "X-authentik-entitlements"
+    "X-authentik-email"
+    "X-authentik-name"
+    "X-authentik-uid"
+  )) -}}
+
+  {{- if or (not $auth.internalHost) (not $auth.externalHost) -}}
+    {{- fail "Ingress - Expected [integrations.nginx.auth.internalHost] and [integrations.nginx.auth.externalHost] to be set" -}}
+  {{- end -}}
+
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-method" "GET" -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-response-headers" (join "," $respHeaders) -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-snippet" "proxy_set_header X-Forwarded-Host $http_host;" -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/backend-protocol" "HTTPS" -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/force-ssl-redirect" "true" -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-url" (printf "http://%s/outpost.goauthentik.io/auth/nginx" $auth.internalHost) -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-signin" (printf "https://%s/outpost.goauthentik.io/start?rd=$scheme://$http_host$escaped_request_uri" $auth.externalHost) -}}
+{{- end -}}
+
+{{- define "tc.v1.common.lib.ingress.integration.nginx.auth.authelia" -}}
+  {{- $objectData := .objectData -}}
+  {{- $auth := .auth -}}
+
+  {{- if and $auth.respondHeaders (not (kindIs "slice" $auth.responseHeaders)) -}}
+    {{- fail (printf "Ingress - Expected [integrations.nginx.auth.responseHeaders] to be a [slice], but got [%s]" (kindOf $auth.responseHeaders)) -}}
+  {{- end -}}
+
+  {{- $respHeaders := ($auth.responseHeaders | default (list
+    "Remote-User"
+    "Remote-Name"
+    "Remote-Groups"
+    "Remote-Email"
+  )) -}}
+
+  {{- if or (not $auth.internalHost) (not $auth.externalHost) -}}
+    {{- fail "Ingress - Expected [integrations.nginx.auth.internalHost] and [integrations.nginx.auth.externalHost] to be set" -}}
+  {{- end -}}
+
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-method" "GET" -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-url" (printf "http://%s/api/verify" $auth.internalHost) -}}
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/auth-signin" (printf "https://%s?rm=$request_method" $auth.externalHost) -}}
+{{- end -}}

charts/library/common/templates/lib/ingress/integrations/nginx/_ipWhiteList.tpl

@@ -0,0 +1,12 @@
+{{- define "tc.v1.common.lib.ingress.integration.nginx.ipWhitelist" -}}
+  {{- $objectData := .objectData -}}
+  {{- $whiteList := .whiteList -}}
+
+  {{- if not (kindIs "slice" $whiteList) -}}
+    {{- fail (printf "Ingress - Expected [integrations.nginx.ipWhitelist] to be a [slice], but got [%s]" (kindOf $whiteList)) -}}
+  {{- end -}}
+
+  {{- if $whiteList -}}
+    {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/whitelist-source-range" (join "," $whiteList) -}}
+  {{- end -}}
+{{- end -}}

charts/library/common/templates/lib/ingress/integrations/nginx/_themePark.tpl

@@ -0,0 +1,18 @@
+{{- define "tc.v1.common.lib.ingress.integration.nginx.themePark" -}}
+  {{- $objectData := .objectData -}}
+  {{- $theme := .themePark -}}
+  {{- if and $theme $theme.enabled (not (kindIs "string" $theme.css)) -}}
+    {{- fail (printf "Ingress - Expected [integrations.nginx.themepark.css] to be a [string], but got [%s]" (kindOf $theme.css)) -}}
+  {{- end -}}
+
+  {{- $snippet := (list
+    "proxy_set_header Accept-Encoding \"\";"
+    "sub_filter"
+    "'</head>'"
+    (printf "'<link rel=\"stylesheet\" type=\"text/css\" href=\"%s\">" $theme.css)
+    "</head>';"
+    "sub_filter_once on;"
+  ) -}}
+
+  {{- $_ := set $objectData.annotations "nginx.ingress.kubernetes.io/configuration-snippet" (join "\n" $snippet) -}}
+{{- end -}}

charts/library/common/values.yaml

@@ -665,6 +665,21 @@ ingress:
         #     # Optional, by default will try to
         #     # "lookup" the namespace based on the name
         #     namespace: ""
+      nginx:
+        enabled: false
+        themepark:
+          enabled: false
+          css: ""
+        ipWhitelist: []
+        auth:
+          # empty to disable, options: "authentik" or "authelia"
+          type: ""
+          # Internal Domain name + port to reach the auth provider, excluding http(s)
+          internalHost: ""
+          # External (ingress) Domain name to reach the auth provider, excluding http(s)
+          externalHost: ""
+          # Optional: override default response headers
+          responseHeaders: []
       homepage:
         enabled: false
         # Default: chart name

cspell.config.yaml

@@ -333,6 +333,7 @@ words:
   - statping
   - steamcommunica
   - steammasterser
+  - stylesheet
   - subchart
   - sublist
   - subquestion