I could not find anything by just googling, does Helm support private values?
So I have my chart and my values.yaml
privateProp: hello
publicProp: world
I have some values that I want to exposed to the end user of my chart and others that I do not want, however those "private" values are being used in many places.
For example: publicProps is overridable by the user of the chart, but I would like to block access to privateProp, however it is reused in many places:
containers:
name: {{.Values.privateProp}}
nodeSelector:
name: {{.Values.privateProp}}
I saw there is {{$privateProp := "hello"}}, but it is not clear how I can access it elsewhere in my files
How can I achieve this?
Ok, I have found a solution to my problem.
You can create a file called _variables.tpl, the name does not matter
and then declare a variable:
{{- define "privateProp" -}}
{{- print "hello" -}}
{{- end -}}
and then you can use it wherever you want in your chart by doing this:
spec:
containers:
- name: {{ .Values.dashboard.containers.name }}
image: {{ .Values.dashboard.containers.image.repository }}:{{ .Values.dashboard.containers.image.tag }}
imagePullPolicy: Always
ports:
- containerPort: {{ include "privateProp" . }} # <== This
Related
Struggling with some helm templating...
I'm trying to pass a separate yaml file with springboot parameters to helm, and have them split by environment... then I want to pass the environment to helm using --set env=staging
Feels like I've tried everything but clearly I'm lacking a fundamental understanding...
My _helpers.tpl contains these:
{{- define "env" }}
{{- printf "%s" .Values.env }}
{{- end }}
{{ define "configmap.metadata" }}
name: {{ .Values.name }}-config
{{ end }}
{{ define "configmap.properties" }}
{{ index .Values.environment (include "env" .) "properties" | indent 4 }}
{{ end }}
The template for the config map:
apiVersion: v1
kind: ConfigMap
metadata:
{{ include "configmap.metadata" . }}
data:
app.properties: |-
{{ include "configmap.properties" .}}
And the yaml file containing the properties looks like this:
environment:
staging:
properties:
spring:
datasource:
url: something
username: something
password: something
app1:
key: something
secret: something
baseUri: something
app2:
bootstrap_server: something
bootstrap_port: something
registry_schema: something
production:
properties:
spring:
etc, etc
And then I want to select the environment using set. I'm testing with:
helm template test . -f values.yaml -f properties.yaml --set env=staging
I think I've just tried so many things that I just can't see the wood for the trees! The error I'm seeing is:
Error: template: microservice/templates/configmap.yaml:7:7: executing "microservice/templates/configmap.yaml" at <include "configmap.properties" .>: error calling include: template: microservice/templates/_helpers.tpl:56:76: executing "configmap.properties" at <4>: wrong type for value; expected string; got map[string]interface {}
EDIT:
After tweaking, I'm still getting an error, but I'm seeing something in the configmap.. but I wonder if the error is due to the 8 spaces on the first line..
data:
app.properties: |-
app2:
bootstrap_port: something
bootstrap_server: something
registry_schema: something
app1:
baseUri: something
key: something
secret: something
spring:
datasource:
password: something
url: something
username: something
I think your actual error message is around the way you're using the .Values.environment.production.properties value. It's a YAML map, but the indent function expects it to be a string. You should be able to see some odd indentation and maybe an odd [map spring [map datasource ...]] string if you use the helm template --debug option.
When you go to render the ConfigMap, you need to make sure to do two things. Since the data you have is structured properties, you need to use the lightly-documented toYaml function to convert it back to YAML. This will begin at the first column, so you need to apply the indent function to it, and then you need to make sure the markup that invokes it is also at the first column (indent should be the only thing that supplies indentation).
data:
app.properties: |-
{{ include "configmap.properties" . | indent 4}}
{{/*- starts at column 1, but includes the `indent` function */}}
{{ define "configmap.properties" }}
{{- index .Values.environment (.Values.env) "properties" | toYaml }}
{{/*- starts at first column, includes `toYaml`, does not include `indent` */}}
{{- end }}
I’m trying to defines some variables in order to make my helm chart non-repeatable
I created a helpers file which contains the following section:
{{ $config := .Values.service }}
{{- range .Values.services }}
{{ $config.$serviceName }}
{{- define "{{ $serviceName }}.selectorLabels" -}}
app.kubernetes.io/name: {{ .name }}
app.kubernetes.io/instance: {{ .instance }}
{{- end -}}
{{- end -}}
values.yaml:
services:
- service1
- service2
- service3
service:
- service1:
name: service1
- service2:
name: service2
- service3:
name: service3
but it keeps prompting an error for bad character U+0024 ‘$’
Do you know how can I define a variable by other variable?
Neither the Go text/template language, the Sprig extensions, nor Helm's local extensions have a way to define a template with a dynamic name. The name in a define call must be a fixed string. The text/template documentation notes (under "Nested template definitions"):
Template definitions must appear at the top level of the template.... The define action names the template being created by providing a string constant.
However, templates take a (single) parameter. Instead of trying to define a separate template for each dynamically-specified value, you could define a single template that produces this content, and then call it with the dynamic settings.
{{- define "selectorLabels" -}}{{/* <-- fixed name */-}}
{{/* .name is relative to the template parameter . */-}}
app.kubernetes.io/name: {{ .name }}
app.kubernetes.io/instance: {{ .instance }}
{{- end -}}
{{- range .Values.services }}
{{-/* . is one item from the services list */}}
{{ include "selectorLabels" . }}
{{- end -}}
You may find a simpler Helm values structure easier to work with as well. If you decompose .Values.service, it is a list, where each list is a single-item dictionary, where the key comes from a separate list. You might structure this as a single flat list of settings dictionaries, embedding the item name as a name: value within the structure (like for example the containers: list in a pod spec).
services:
- name: service1
instance: foo
- name: service2
instance: bar
- name: service3
instance: baz
I'm using Helm for to deploy multiple K8s deployments. In some deployments I need to include extra environment variables, but for the majority of deployment the standard env. variables are enough. I would like to have named template for those deployments that must have extra env. variables.
Can I include a named template only if the named template exist?
Something like this:
{{ range $idx, $svc := .Values.services }}
kind: Deployment
metadata:
name: {{ $svc.name }}
spec:
containers:
- name: {{ $svc.name }}
env:
- name: JAVA_OPTS
- value: {{ $svc.javaOpts }}
# if template_exists (print $svc.name "-env")
{{ include (print $svc.name "-env") . | indent 12 }}
# end
{{- end -}}
It's in pseudo-code. How to do the # if part?
Thank you.
The easiest way would be to add additional key like templateExists: true to your services and check it with a simple if statement in your deployment:
{{- if $svc.templateExists }}
{{ include (print $svc.name "-env") . | indent 8 }}
{{- end -}}
services:
svc1:
templateExists: true
name: svc1
javaOpts: "-Xms128m -Xmx512m"
svc2:
name: svc2
javaOpts: "-Xms256m -Xmx512m"
Here is a solution that I came up now. I check if there are any files in the chart that matches the pattern [service]-env.yaml and if there are then I include the content of that file in the deployment.
{{- range $path, $_ := $f.Glob "**-env.yaml" }}
{{- if contains $svc.app.name $path }}
{{ $f.Get $path | indent 8 }}
{{- end }}
{{- end }}
That way, for services that require extra env. variables we can include a file in files/service-env.yaml and those variables will be added to the deployment. For services that do not require such variables, it's left empty.
I have 2 different values.yaml files per stage and production environment such as values.dev.yaml > values.prod.yaml and using with Helm 3. I would like to learn the best practices how to pass environment variables per environments.For instance we need to set different parameters to NODE_ENV variable.
-Should I specify the variable as hard coded as below and pass the environment variables when running helm upgrade/install command with --set flag?
-What is the correct way to use go template to do this. Can we specify something {{ .Values.node_env.value}} and then pass this env value in values yaml and use only -f values.yaml flag?
containers:
- name: {{ .Chart.Name }}
securityContext:
{{- toYaml .Values.securityContext | nindent 12 }}
image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
imagePullPolicy: {{ .Values.image.pullPolicy }}
ports:
- name: http
containerPort: 8080
protocol: TCP
resources:
{{- toYaml .Values.resources | nindent 12 }}
env:
- name: "NODE_ENV"
value: "stage"
- name: "NODE_ENV"
value: "production"
If you have one value file per environment (it is not clear to me this is your case.) like values.prod.yaml (for prod) and values.dev.yaml (for dev), then your templeate can look like this.
This will cause the template to look for extraEnv: in your values{dev/prod}.yaml and iterate over all key/values from that section.
env:
{{- range $key, $value := .Values.extraEnv }}
- name: {{ $key }}
value: {{ $value | quote }}
{{- end }}
In your values.dev.yaml files you add all your KEY: values that are specific for this environment. Note you can have multiple key values here, all of them will be loaded. In this case we have NODE_ENV, ANOTHER_KEY, YET_ANOTHER_KEY - all of them will be loaded.
extraEnv:
NODE_ENV: stage
ANOTHER_KEY: value
YET_ANOTHER_KEY: value
same in your values.prod.yaml multiple KEY: value pairs can be specified and all of them will be loaded.
extraEnv:
NODE_ENV: production
ANOTHER_KEY: value
I'm starting to write helm charts for our services.
There are two things I'm not sure how they are supposed to work or what to do with them.
First: the release name. When installing a chart, you specify a name which helm uses to create a release. This release name is often referenced within a chart to properly isolate chart installs from each other? For example the postgres chart contains:
{{- define "postgresql.fullname" -}}
{{- $name := default .Chart.Name .Values.nameOverride -}}
{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" -}}
{{- end -}}
Which is then used for the service:
metadata:
name: {{ template "postgresql.fullname" . }}
It does look like "myrelease-postgresql" in the end in kubernetes.
I wonder what a good release name is? What is typically used for this? A version? Or some code-name like the ubuntu releases?
Second: referencing values.
My chart uses postgresql as a sub-chart. I'd like to not duplicate the way the value for the name of the postgresql service is created (see snipped above).
Is there a way I can reference the service name of a sub-chart or that template define {{ template "postgresql.fullname" . }} in the parent chart? I need it to pass it into my service as database host (which works if I hardcode everything but that cannot be the meaning of this).
I tried:
env:
- name: DB_HOST
value: {{ template "mychart.postgresql.fullname" . }}
But that lead into an error message:
template "mychart.postgresql.fullname" not defined
I've seen examples of Charts doing similar things, like the odoo chart. But in here that logic how the postgresql host name is created is copied and an own define in the template is created.
So is there a way to access sub-chart names? Or values or template defines?
Thanks!
Update after some digging:
According to Subcharts and Globals the templates are shared between charts.
So what I can do is this:
In my chart in _helpers.tpl I add (overwrite) the postgres block:
{{- define "postgresql.fullname" -}}
{{- $name := .Values.global.name -}}
{{- printf "%s-%s" $name "postgresql" | trunc 63 | trimSuffix "-" -}}
{{- end -}}
So this value is used when the sub-chart is deployed. I cannot reference all values or the chart name in here as it will be different in the sub-chart - so I used a global value.
Like this I know the value of the service that is created in the sub-chart.
Not sure if this is the best way to do this :-/
Are you pulling in postgresql as a subchart of your chart (via your chart's requirements.yaml)? If so, both the postgresql (sub) chart and your chart will have the same .Release.Name - thus, you could specify your container's environment as
env:
- name: DB_HOST
value: {{ printf "%s-postgresql" .Release.Name }}
if you override postgresql's name by adding the following to your chart's values.yaml:
postgresql:
nameOverride: your-postgresql
then your container's env would be:
env:
- name: DB_HOST
value: {{ printf "%s-%s" .Release.Name .Values.postgresql.nameOverride }}
You can overwrite the values of the subchart with the values of the parent chart as described here:
https://helm.sh/docs/chart_template_guide/subcharts_and_globals/
I don't think it's possible (and it also doesn't make sense) to override the template name of the subchart.
What I would do is define the database service name in the .Values files both in the parent and sub charts and let helm override the one in the subchart - that way you will always have the database name in the parent chart. This would however mean that the service name of the database should not be {{ template "name" . }}, but something like {{ .Values.database.service.name }}
mychart/.Values
mysubchart:
service:
name: my-database
mychart/templates/deployment.yaml
env:
- name: DB_HOST
value: {{ .Values.mysubchart.service.name }}
mychart/charts/mysubchart/.Values
service:
name: my-database
mychart/charts/mysubchart/templates/service.yaml:
apiVersion: v1
kind: Service
metadata:
name: {{ .Values.service.name }}
Another way is to use global chart values, also described in https://helm.sh/docs/chart_template_guide/subcharts_and_globals/
For values in the helper.tpl instead of values.yaml
To access a value from a chart you do the following:
{{ template "keycloak.fullname" . }}
To access a value from a sub chart
{{ template "keycloak.fullname" .Subcharts.keycloak }}
You could import values from a sub chart as described here: https://helm.sh/docs/topics/charts/#importing-child-values-via-dependencies.
However there is a caveat. This works not for values defined at the root level in the values.yaml.
See this issue for more information: https://github.com/helm/helm/issues/9817