[COMMON] New affinities templates

Pod/Node affinity may be important to set, especially in the context of
statefulset.
These templates helps in order to make it work.

Issue-ID: OOM-1720
Signed-off-by: Sylvain Desbureaux <sylvain.desbureaux@orange.com>
Change-Id: Ic2ce2fc1188c4181bd8042b8410c1b810f50bff7
diff --git a/kubernetes/common/common/templates/_affinities.tpl b/kubernetes/common/common/templates/_affinities.tpl
new file mode 100644
index 0000000..f0802be
--- /dev/null
+++ b/kubernetes/common/common/templates/_affinities.tpl
@@ -0,0 +1,109 @@
+{{/* vim: set filetype=mustache: */}}
+{{/*
+# Copyright © 2020 Bitnami, Orange
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+*/}}
+
+{{/*
+Return a soft nodeAffinity definition
+{{ include "common.affinities.nodes.soft" (dict "key" "FOO" "values" (list "BAR" "BAZ")) -}}
+*/}}
+{{- define "common.affinities.nodes.soft" -}}
+preferredDuringSchedulingIgnoredDuringExecution:
+  - preference:
+      matchExpressions:
+        key: {{ .key }}
+        operator: In
+        values:
+          {{- range .values }}
+          - {{ . }}
+          {{- end }}
+    weight: 1
+{{- end -}}
+
+{{/*
+Return a hard nodeAffinity definition
+{{ include "common.affinities.nodes.hard" (dict "key" "FOO" "values" (list "BAR" "BAZ")) -}}
+*/}}
+{{- define "common.affinities.nodes.hard" -}}
+requiredDuringSchedulingIgnoredDuringExecution:
+  nodeSelectorTerms:
+    - matchExpressions:
+        key: {{ .key }}
+        operator: In
+        values:
+          {{- range .values }}
+          - {{ . }}
+          {{- end }}
+{{- end -}}
+
+{{/*
+Return a nodeAffinity definition
+{{ include "common.affinities.nodes" (dict "type" "soft" "key" "FOO" "values" (list "BAR" "BAZ")) -}}
+*/}}
+{{- define "common.affinities.nodes" -}}
+  {{- if eq .type "soft" }}
+    {{- include "common.affinities.nodes.soft" . -}}
+  {{- else if eq .type "hard" }}
+    {{- include "common.affinities.nodes.hard" . -}}
+  {{- end -}}
+{{- end -}}
+
+{{/*
+Return a soft podAffinity/podAntiAffinity definition
+{{ include "common.affinities.pods.soft" (dict "component" "FOO" "context" $) -}}
+*/}}
+{{- define "common.affinities.pods.soft" -}}
+{{- $component := default "" .component -}}
+preferredDuringSchedulingIgnoredDuringExecution:
+  - podAffinityTerm:
+      labelSelector:
+        matchLabels: {{- (include "common.matchLabels" (dict "dot" .context "matchLabels" (dict))) | nindent 10 }}
+          {{- if not (empty $component) }}
+          {{ printf "app.kubernetes.io/component: %s" $component }}
+          {{- end }}
+      namespaces:
+        - {{ include "common.namespace" .context }}
+      topologyKey: kubernetes.io/hostname
+    weight: 1
+{{- end -}}
+
+{{/*
+Return a hard podAffinity/podAntiAffinity definition
+{{ include "common.affinities.pods.hard" (dict "component" "FOO" "context" $) -}}
+*/}}
+{{- define "common.affinities.pods.hard" -}}
+{{- $component := default "" .component -}}
+requiredDuringSchedulingIgnoredDuringExecution:
+  - labelSelector:
+      matchLabels: {{- (include "common.matchLabels" (dict "dot" .context "matchLabels" (dict))) | nindent 8 }}
+        {{- if not (empty $component) }}
+        {{ printf "app.kubernetes.io/component: %s" $component }}
+        {{- end }}
+    namespaces:
+      - {{ include "common.namespace" .context }}
+    topologyKey: kubernetes.io/hostname
+{{- end -}}
+
+{{/*
+Return a podAffinity/podAntiAffinity definition
+{{ include "common.affinities.pods" (dict "type" "soft" "key" "FOO" "values" (list "BAR" "BAZ")) -}}
+*/}}
+{{- define "common.affinities.pods" -}}
+  {{- if eq .type "soft" }}
+    {{- include "common.affinities.pods.soft" . -}}
+  {{- else if eq .type "hard" }}
+    {{- include "common.affinities.pods.hard" . -}}
+  {{- end -}}
+{{- end -}}
\ No newline at end of file