Konubinix' opinionated web of thoughts

Helm

Fleeting

A tool to template k8s installations, like kustomize.

debug given values to template

If your values are split into several values.yaml valus-something.yaml and on the fly generated –set instructions, it may become hard to find out why helm template gave the result it did.

A quick trick to understand better what .Values will eventually be is to use a dumb chart that simply does that: dump the .Values. You have to call it with the same command that the one you want to debug, but with the additional -f ./mychart/values.yaml first.

I could use helm create to build the dump template, but then I have to remove a lot of files. I’d rather build the only two files I need manually.

mkdir -p dumb
cd dumb
cat<<EOF > Chart.yaml
apiVersion: v2
name: dumb
description: Some dumb helm chart to display the values
type: application
version: 0.1.0
appVersion: "1.16.0"
EOF

mkdir templates

cat<<EOF > templates/dump-values.yaml
{{ .Values | toYaml }}
EOF

Then, if my command was:

helm template releasename ./mychart -f somevalues.yaml --set some.thing=value

I simply call

helm template releasename ./dumb -f ./mychart/values.yaml -f somevalues.yaml --set some.thing=value

chart

list available charts

If using oci

crane ls registry-1.docker.io/bitnamicharts 2>&1

Error: reading tags for registry-1.docker.io/bitnamicharts: GET https://registry-1.docker.io/v2/bitnamicharts/tags/list?n=1000: UNAUTHORIZED: authentication required; [map[Action:pull Class: Name:bitnamicharts Type:repository]]

unfortunately, this is a bad example because we don’t have the right to list them. I don’t know if this is doable.

If using standard https interface

repo="https://blockscout.github.io/helm-charts"
curl -s https://blockscout.github.io/helm-charts/index.yaml|yq -r '.entries|keys[]'

autoscout
blockscout-admin
blockscout-ens
blockscout-points
blockscout-proxy-verifier
blockscout-stack
chainscout
cloudflare-tunnel
da-indexer
eth-rpc-exporter
eth-tx-summary-api
graph-node
metabase
pganalyzer
quicknode-marketplace-integration
redstone-mud
remix-project
rpc-node
scoutcloud
smart-contract-verification
smart-guessr
sql-exporter
swapscout
verification-app
visualizer
yopass

list available versions

If using oci

repo="oci://registry-1.docker.io/bitnamicharts"
chart="postgresql"
crane ls "${repo#oci://*}/${chart}"|grep --invert-match sha256|sort --reverse --version-sort|head

16.0.5
16.0.4
16.0.3
16.0.2
16.0.1
16.0.0
15.5.38
15.5.37
15.5.36
15.5.35

If using standard https interface

repo="https://blockscout.github.io/helm-charts"
chart="blockscout-stack"
curl -s "${repo}/index.yaml"|yq --raw-output ".entries[\"${chart}\"][].version"|sort --reverse --version-sort|head

1.6.8
1.6.7
1.6.6
1.6.5
1.6.4
1.6.3
1.6.2
1.6.1
1.6.0
1.5.1

download for inspection

TMP="$(mktemp -d)"
trap "rm -rf '${TMP}'" 0

pushd "${TMP}" > /dev/null
{
    helm pull "oci://registry-1.docker.io/bitnamicharts/postgresql" --version 15.5.23 2>&1
    ls
}
popd > /dev/null

Pulled: registry-1.docker.io/bitnamicharts/postgresql:15.5.23
Digest: sha256:9876f3f4c152acd448c6ec62d0915ff17a6b8f7c5e98e63ca296abfb92de8df0
postgresql-15.5.23.tgz

install using oci

make sure to have the appropriate tag in the Chart.yaml file and that the name is the one you want.

then

helm push /app/package.tgz oci://registry

Don’t specify neither the repository or the tag, helm will read the chart.yaml

So, if the chart contains name: something and version: 0.1.0, then the published image will be registry/repository:version

helm pull oci://registry/repository/name –version tag helm install oci://registry/repository/name –version tag

beware non deterministic package

running helm package twice result in two packages with different sha256sum

https://github.com/helm/helm/issues/3612

So far, I used this workaround to get a hash

tar xf package.tgz && sed -i '/^generated:/d' ${name}/Chart.lock && find ${name} -type f -exec sha256sum {} \;|sort | sha256sum | cut -c 1-60 > hash.txt

Hooks

does not work with post-renderer

https://github.com/helm/helm/issues/7891

post-renderer

Notes linking here