Tanka/Jsonnet - Howto loop over templates/imports? - kubernetes

Question

i am trying to create multiple grafana-instances with slightly different config-files with tanka. The following works, as long as the the configmap.grafana_ini is in-place. But this becomes very unreadable with a growing config. So i am looking for a way to move the configmaps to their own file and import.
But if i move that to it's own file and use an import/str i am getting a "computed imports are not allowed" error or the instance-variable becomes unknown.
local tanka = import 'github.com/grafana/jsonnet-libs/tanka-util/main.libsonnet';
local helm = tanka.helm.new(std.thisFile);
local k = import 'github.com/grafana/jsonnet-libs/ksonnet-util/kausal.libsonnet';
(import 'config.libsonnet') +
{
local configMap = k.core.v1.configMap,
local container = k.core.v1.container,
local stateful = k.apps.v1.statefulSet,
local ingrdatasourcesess = k.networking.v1.ingress,
local port = k.core.v1.containerPort,
local service = k.core.v1.service,
local pvc = k.core.v1.persistentVolumeClaim,
local ports = [port.new('http', 3000)],
grafana: {
g(instance):: {
local this = self,
deployment:
stateful.new(
name='grafana-' + instance.handle,
replicas=1,
containers=[
container.new(
name='grafana-' + instance.handle,
image=$._config.grafana.image + instance.theme + ':' + $._config.grafana.version
)
+ container.withPorts(ports),
],
)
+ stateful.metadata.withLabels({ 'io.kompose.service': 'grafana-' + instance.handle })
+ stateful.configMapVolumeMount(this.configMaps.grafana_ini, '/etc/grafana/grafana.ini', k.core.v1.volumeMount.withSubPath('grafana.ini'))
+ stateful.spec.withServiceName('grafana-' + instance.handle)
+ stateful.spec.selector.withMatchLabels({ 'io.kompose.service': 'grafana-' + instance.handle })
+ stateful.spec.template.metadata.withLabels({ 'io.kompose.service': 'grafana-' + instance.handle })
+ stateful.spec.template.spec.withImagePullSecrets({
name: 'registry.gitlab.com',
})
+ stateful.spec.template.spec.withRestartPolicy('Always'),
service:
k.util.serviceFor(self.deployment)
+ service.mixin.spec.withType('ClusterIP'),
configMaps: {
grafana_ini:
configMap.new(
'grafana-ini-' + instance.handle, {
'grafana.ini': std.manifestIni(
{
main: {
app_mode: 'production',
instance_name: instance.handle,
},
sections: {
server: {
protocol: 'http',
http_port: '3000',
domain: 'dashboard.' + $._config.ingress.realm + '.' + $._config.ingress.tld + '/' + instance.handle + '/',
root_url: $._config.ingress.protocol + 'dashboard.' + $._config.ingress.realm + '.' + $._config.ingress.tld + '/' + instance.handle + '/',
serve_from_sub_path: true,
},
},
}
),
}
),
},
},
deploys: [self.g(instance) for instance in $._config.grafana.instances],
},
}
Here is the config-part:
{
_config+:: {
grafana+: {
image: 'registry.gitlab.com/xxx/frontend/grafana/',
version: 'v7.3.7',
client_secret: 'xyz',
adminusername: 'admin',
adminpassword: 'admin',
instances: [
{
name: "xxx's Grafana",
handle: 'xyz',
theme: 'xxx',
alerting: 'false',
volume_size: '200M',
default: true,
allow_embedding: false,
public: 'false',
secret_key: 'xxxx',
email: {
host: '',
user: '',
password: '',
from_address: '',
from_name: '',
},
datasources: [
{
name: 'xxx Showcase',
type: 'influxdb',
access: 'proxy',
url: 'http://influx:8086',
database: 'test123',
user: 'admin',
password: 'admin',
editable: false,
isDefault: false,
version: 1
},
],
dashboards: [
{
src: 'provisioning/dashboards/xxx_showcase_dashboard.json',
datasource: 'xxx Showcase',
title: 'xxx office building',
template: true,
},
],
},
],
},
},
}
EDITED, as suggested by 2nd post.
greetings,
strowi

Answer 1

Thanks for clarifying, find below a possible solution, note I trimmed down parts of your original files, for better readability.
I think that the main highlight here is the iniFile() function, so that we can explicitly pass (config, instance) to it.
main.jsonnet
local tanka = import 'github.com/grafana/jsonnet-libs/tanka-util/main.libsonnet';
local helm = tanka.helm.new(std.thisFile);
local k = import 'github.com/grafana/jsonnet-libs/ksonnet-util/kausal.libsonnet';
(import 'config.libsonnet') +
{
local configMap = k.core.v1.configMap,
local container = k.core.v1.container,
local stateful = k.apps.v1.statefulSet,
local ingrdatasourcesess = k.networking.v1.ingress,
local port = k.core.v1.containerPort,
local service = k.core.v1.service,
local pvc = k.core.v1.persistentVolumeClaim,
local ports = [port.new('http', 3000)],
grafana: {
g(instance):: {
local this = self,
/* <snip...> */
configMaps: {
local inilib = import 'ini.libsonnet',
grafana_ini:
configMap.new(
'grafana-ini-' + instance.handle, inilib.iniFile($._config, instance)
),
},
},
deploys: [self.g(instance) for instance in $._config.grafana.instances],
},
}
config.libsonnet
{
_config+:: {
// NB: added below dummy ingress field
ingress:: {
realm:: 'bar',
tld:: 'foo.tld',
protocol:: 'tcp',
},
grafana+: {
image: 'registry.gitlab.com/xxx/frontend/grafana/',
version: 'v7.3.7',
client_secret: 'xyz',
adminusername: 'admin',
adminpassword: 'admin',
instances: [
{
name: "xxx's Grafana",
handle: 'xyz',
/* <snip...> */
},
],
},
},
}
ini.libsonnet
{
iniFile(config, instance):: {
'grafana.ini': std.manifestIni(
{
main: {
app_mode: 'production',
instance_name: instance.handle,
},
sections: {
server: {
protocol: 'http',
http_port: '3000',
domain: 'dashboard.' + config.ingress.realm + '.' + config.ingress.tld + '/' + instance.handle + '/',
root_url: config.ingress.protocol + 'dashboard.' + config.ingress.realm + '.' + config.ingress.tld + '/' + instance.handle + '/',
serve_from_sub_path: true,
},
},
}
),
},
}