Change some practice

practice/18.templating/libchart/templates/_configmap.yaml

@@ -0,0 +1,10 @@
+{{- define "libchart.configmap.tpl" -}}
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: {{ .Release.Name | printf "%s-%s" .Chart.Name }}
+data: {}
+{{- end -}}
+{{- define "libchart.configmap" -}}
+{{- include "libchart.util.merge" (append . "libchart.configmap.tpl") -}}
+{{- end -}}

practice/18.templating/libchart/templates/_util.yaml

@@ -0,0 +1,13 @@
+{{- /*
+libchart.util.merge will merge two YAML templates and output the result.
+This takes an array of three values:
+- the top context
+- the template name of the overrides (destination)
+- the template name of the base (source)
+*/}}
+{{- define "libchart.util.merge" -}}
+{{- $top := first . -}}
+{{- $overrides := fromYaml (include (index . 1) $top) | default (dict ) -}}
+{{- $tpl := fromYaml (include (index . 2) $top) | default (dict ) -}}
+{{- toYaml (merge $overrides $tpl) -}}
+{{- end -}}