docs(README): add OCI registry

.gitea/scripts/add-annotations.sh

@@ -1,61 +1,65 @@
 #!/bin/bash
 
-set -e
+set -e -o pipefail
 
-CHART_FILE="Chart.yaml"
+chart_file="Chart.yaml"
-if [ ! -f "${CHART_FILE}" ]; then
+if [ ! -f "${chart_file}" ]; then
-  echo "ERROR: ${CHART_FILE} not found!" 1>&2
+  echo "ERROR: ${chart_file} not found!" 1>&2
   exit 1
 fi
 
-DEFAULT_NEW_TAG="$(git tag --sort=-version:refname | head -n 1)"
+default_new_tag="$(git tag --sort=-version:refname | head -n 1)"
-DEFAULT_OLD_TAG="$(git tag --sort=-version:refname | head -n 2 | tail -n 1)"
+default_old_tag="$(git tag --sort=-version:refname | head -n 2 | tail -n 1)"
 
 if [ -z "${1}" ]; then
-  read -p "Enter start tag [${DEFAULT_OLD_TAG}]: " OLD_TAG
+  echo "Enter start tag [${default_old_tag}]:"
-  if [ -z "${OLD_TAG}" ]; then
+  read -r old_tag
-    OLD_TAG="${DEFAULT_OLD_TAG}"
+  if [ -z "${old_tag}" ]; then
+    old_tag="${default_old_tag}"
   fi
 
-  while [ -z "$(git tag --list "${OLD_TAG}")" ]; do
+  while [ -z "$(git tag --list "${old_tag}")" ]; do
-    echo "ERROR: Tag '${OLD_TAG}' not found!" 1>&2
+    echo "ERROR: Tag '${old_tag}' not found!" 1>&2
-    read -p "Enter start tag [${DEFAULT_OLD_TAG}]: " OLD_TAG
+    echo "Enter start tag [${default_old_tag}]:"
-    if [ -z "${OLD_TAG}" ]; then
+    read -r old_tag
-      OLD_TAG="${DEFAULT_OLD_TAG}"
+    if [ -z "${old_tag}" ]; then
+      old_tag="${default_old_tag}"
     fi
   done
 else
-  OLD_TAG=${1}
+  old_tag=${1}
-  if [ -z "$(git tag --list "${OLD_TAG}")" ]; then
+  if [ -z "$(git tag --list "${old_tag}")" ]; then
-    echo "ERROR: Tag '${OLD_TAG}' not found!" 1>&2
+    echo "ERROR: Tag '${old_tag}' not found!" 1>&2
     exit 1
   fi
 fi
 
 if [ -z "${2}" ]; then
-  read -p "Enter end tag [${DEFAULT_NEW_TAG}]: " NEW_TAG
+  echo "Enter end tag [${default_new_tag}]:"
-  if [ -z "${NEW_TAG}" ]; then
+  read -r new_tag
-    NEW_TAG="${DEFAULT_NEW_TAG}"
+  if [ -z "${new_tag}" ]; then
+    new_tag="${default_new_tag}"
   fi
 
-  while [ -z "$(git tag --list "${NEW_TAG}")" ]; do
+  while [ -z "$(git tag --list "${new_tag}")" ]; do
-    echo "ERROR: Tag '${NEW_TAG}' not found!" 1>&2
+    echo "ERROR: Tag '${new_tag}' not found!" 1>&2
-    read -p "Enter end tag [${DEFAULT_NEW_TAG}]: " NEW_TAG
+    echo "Enter end tag [${default_new_tag}]:"
-    if [ -z "${NEW_TAG}" ]; then
+    read -r new_tag
-      NEW_TAG="${DEFAULT_NEW_TAG}"
+    if [ -z "${new_tag}" ]; then
+      new_tag="${default_new_tag}"
     fi
   done
 else
-  NEW_TAG=${2}
+  new_tag=${2}
 
-  if [ -z "$(git tag --list "${NEW_TAG}")" ]; then
+  if [ -z "$(git tag --list "${new_tag}")" ]; then
-    echo "ERROR: Tag '${NEW_TAG}' not found!" 1>&2
+    echo "ERROR: Tag '${new_tag}' not found!" 1>&2
     exit 1
   fi
 fi
 
-CHANGE_LOG_YAML=$(mktemp)
+change_log_yaml=$(mktemp)
-echo "[]" > "${CHANGE_LOG_YAML}"
+echo "[]" > "${change_log_yaml}"
 
 function map_type_to_kind() {
   case "${1}" in
@@ -80,35 +84,42 @@ function map_type_to_kind() {
   esac
 }
 
-COMMIT_TITLES="$(git log --pretty=format:"%s" "${OLD_TAG}..${NEW_TAG}")"
+commit_titles="$(git log --pretty=format:"%s" "${old_tag}..${new_tag}")"
 
-echo "INFO: Generate change log entries from ${OLD_TAG} until ${NEW_TAG}"
+echo "INFO: Generate change log entries from ${old_tag} until ${new_tag}"
 
 while IFS= read -r line; do
   if [[ "${line}" =~ ^([a-zA-Z]+)(\([^\)]+\))?\:\ (.+)$ ]]; then
-    TYPE="${BASH_REMATCH[1]}"
+    type="${BASH_REMATCH[1]}"
-    KIND=$(map_type_to_kind "${TYPE}")
+    kind=$(map_type_to_kind "${type}")
 
-    if [ "${KIND}" == "skip" ]; then
+    if [ "${kind}" == "skip" ]; then
       continue
     fi
 
-    DESC="${BASH_REMATCH[3]}"
+    desc="${BASH_REMATCH[3]}"
 
-    echo "- ${KIND}: ${DESC}"
+    echo "- ${kind}: ${desc}"
 
-    jq --arg kind "${KIND}" --arg description "${DESC}" '. += [ $ARGS.named ]' < "${CHANGE_LOG_YAML}" > "${CHANGE_LOG_YAML}.new"
+    jq --arg kind "${kind}" --arg description "${desc}" '. += [ $ARGS.named ]' < "${change_log_yaml}" > "${change_log_yaml}.new"
-    mv "${CHANGE_LOG_YAML}.new" "${CHANGE_LOG_YAML}"
+    mv "${change_log_yaml}.new" "${change_log_yaml}"
 
   fi
-done <<< "${COMMIT_TITLES}"
+done <<< "${commit_titles}"
 
-if [ -s "${CHANGE_LOG_YAML}" ]; then
+if [ -s "${change_log_yaml}" ]; then
-  yq --inplace --input-format json --output-format yml "${CHANGE_LOG_YAML}"
+  yq --inplace --input-format json --output-format yml "${change_log_yaml}"
-  yq --no-colors --inplace ".annotations.\"artifacthub.io/changes\" |= loadstr(\"${CHANGE_LOG_YAML}\") | sort_keys(.)" "${CHART_FILE}"
+  yq --no-colors --inplace ".annotations.\"artifacthub.io/changes\" |= loadstr(\"${change_log_yaml}\") | sort_keys(.)" "${chart_file}"
 else
-  echo "ERROR: Changelog file is empty: ${CHANGE_LOG_YAML}" 1>&2
+  echo "ERROR: Changelog file is empty: ${change_log_yaml}" 1>&2
   exit 1
 fi
 
-rm "${CHANGE_LOG_YAML}"
+rm "${change_log_yaml}"
+
+regexp=".*-alpha-[0-9]+(\.[0-9]+){,2}$"
+if [[ "${new_tag}" =~ $regexp ]]; then
+  yq --inplace '.annotations."artifacthub.io/prerelease" = "true"' "${chart_file}"
+else
+  yq --inplace '.annotations."artifacthub.io/prerelease" = "false"' "${chart_file}"
+fi

.gitea/workflows/artifacthub-metadata.yaml

@@ -0,0 +1,41 @@
+name: Upload ArtifactHub Metadata
+
+on:
+  schedule:
+    - cron: '0 3 1 * *'
+  workflow_dispatch:
+
+jobs:
+  upload-metadata:
+    name: "Upload artifacthub-repo.yml to OCI registry"
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v6.0.2
+    - uses: docker/login-action@v3.7.0
+      with:
+        registry: ${{ github.server_url }}
+        username: ${{ github.repository_owner }}
+        password: ${{ secrets.GIT_CRYPTIC_SYSTEMS_PACKAGE_REGISTRY_TOKEN }}
+    - uses: oras-project/setup-oras@v1.2.4
+      with:
+        version: 1.3.0 # renovate: datasource=github-tags depName=oras-project/oras extractVersion='^v?(?<version>.*)$'
+    - name: Extract meta information
+      run: |
+        echo "GITEA_SERVER_HOSTNAME=$(echo "${GITHUB_SERVER_URL}" | cut -d '/' -f 3)" >> $GITHUB_ENV
+        echo "PACKAGE_VERSION=${GITHUB_REF#refs/tags/}" >> $GITHUB_ENV
+        echo "REPOSITORY_NAME=$(echo ${GITHUB_REPOSITORY} | cut -d '/' -f 2 | sed --regexp-extended 's/-charts?//g')" >> $GITHUB_ENV
+        echo "REPOSITORY_OWNER=$(echo ${GITHUB_REPOSITORY} | cut -d '/' -f 1)" >> $GITHUB_ENV
+    - name: Push artifacthub-repo.yml
+      run: |
+        oras push ${GITEA_SERVER_HOSTNAME}/${REPOSITORY_OWNER}/${REPOSITORY_NAME}:artifacthub.io \
+          --config /dev/null:application/vnd.cncf.artifacthub.config.v1+yaml \
+          artifacthub-repo.yml:application/vnd.cncf.artifacthub.repository-metadata.layer.v1.yaml
+    - name: Push public cosign key
+      env:
+        COSIGN_PUBLIC_KEY: ${{ vars.COSIGN_PUBLIC_KEY }}
+      run: |
+        echo "${COSIGN_PUBLIC_KEY}" > cosign.pub
+        oras push ${GITEA_SERVER_HOSTNAME}/${REPOSITORY_OWNER}/${REPOSITORY_NAME}:cosign.pub \
+          --artifact-type application/vnd.dev.cosign.public-key.v1 \
+          --annotation org.opencontainers.image.title=cosign.pub \
+          cosign.pub:application/vnd.dev.cosign.public-key.v1

.gitea/workflows/generate-readme.yaml

@@ -15,7 +15,7 @@ on:
 jobs:
   generate-parameters:
     container:
-      image: docker.io/library/node:25.4.0-alpine
+      image: docker.io/library/node:25.6.0-alpine
     runs-on: ubuntu-latest
     steps:
     - name: Install tooling

.gitea/workflows/helm.yaml

@@ -17,7 +17,7 @@ jobs:
     - uses: actions/checkout@v6.0.2
     - uses: azure/setup-helm@v4.3.1
       with:
-        version: v4.1.0 # renovate: datasource=github-releases depName=helm/helm
+        version: "v4.0.1" # renovate: datasource=github-tags depName=helm/helm
     - name: Lint helm files
       run: |
         helm lint --values values.yaml .
@@ -28,7 +28,7 @@ jobs:
     - uses: actions/checkout@v6.0.2
     - uses: azure/setup-helm@v4.3.1
       with:
-        version: v4.1.0 # renovate: datasource=github-releases depName=helm/helm
+        version: "v4.0.1" # renovate: datasource=github-tags depName=helm/helm
     - env:
         HELM_UNITTEST_VERSION: v1.0.0 #renovate: datasource=github-releases depName=helm-unittest/helm-unittest
       name: Install helm-unittest

.gitea/workflows/markdown-linters.yaml

@@ -15,7 +15,7 @@ on:
 jobs:
   markdown-link-checker:
     container:
-      image: docker.io/library/node:25.4.0-alpine
+      image: docker.io/library/node:25.6.0-alpine
     runs-on: ubuntu-latest
     steps:
     - name: Install tooling
@@ -30,7 +30,7 @@ jobs:
 
   markdown-lint:
     container:
-      image: docker.io/library/node:25.4.0-alpine
+      image: docker.io/library/node:25.6.0-alpine
     runs-on: ubuntu-latest
     steps:
     - name: Install tooling

.gitea/workflows/release.yaml

@@ -7,14 +7,26 @@ on:
 
 jobs:
   publish-chart:
-    container:
-      image: docker.io/volkerraschek/helm:3.19.2
     runs-on: ubuntu-latest
     steps:
-      - name: Install packages via apk
+      - uses: sigstore/cosign-installer@v4.0.0
+        with:
+          cosign-release: "v2.6.2" # renovate: datasource=github-tags depName=sigstore/cosign
+
+      - uses: azure/setup-helm@v4.3.1
+        with:
+          version: "v4.0.1" # renovate: datasource=github-tags depName=helm/helm
+
+      - name: Install helm plugins
+        env:
+          HELM_SIGSTORE_VERSION: "0.3.0" # renovate: datasource=github-tags depName=sigstore/helm-sigstore extractVersion='^v(?<version>\d+\.\d+\.\d+)$'
+          HELM_SCHEMA_VALUES_VERSION: "2.3.1" # renovate: datasource=github-tags depName=losisin/helm-values-schema-json extractVersion='^v(?<version>\d+\.\d+\.\d+)$'
+          HELM_UNITTEST_VERSION: "1.0.3" # renovate: datasource=github-tags depName=helm-unittest/helm-unittest extractVersion='^v(?<version>\d+\.\d+\.\d+)$'
         run: |
-          apk update
+          helm plugin install --verify=false https://github.com/sigstore/helm-sigstore.git --version "${HELM_SIGSTORE_VERSION}" 1> /dev/null
-          apk add git npm jq yq
+          helm plugin install --verify=false https://github.com/losisin/helm-values-schema-json.git --version "${HELM_SCHEMA_VALUES_VERSION}" 1> /dev/null
+          helm plugin install --verify=false https://github.com/helm-unittest/helm-unittest.git --version "${HELM_UNITTEST_VERSION}" 1> /dev/null
+          helm plugin list
 
       - uses: actions/checkout@v6.0.2
         with:
@@ -28,6 +40,7 @@ jobs:
 
       - name: Extract meta information
         run: |
+          echo "GITEA_SERVER_HOSTNAME=$(echo "${GITHUB_SERVER_URL}" | cut -d '/' -f 3)" >> $GITHUB_ENV
           echo "PACKAGE_VERSION=${GITHUB_REF#refs/tags/}" >> $GITHUB_ENV
           echo "REPOSITORY_NAME=$(echo ${GITHUB_REPOSITORY} | cut -d '/' -f 2 | sed --regexp-extended 's/-charts?//g')" >> $GITHUB_ENV
           echo "REPOSITORY_OWNER=$(echo ${GITHUB_REPOSITORY} | cut -d '/' -f 1)" >> $GITHUB_ENV
@@ -40,22 +53,43 @@ jobs:
           helm dependency build
           helm package --version "${PACKAGE_VERSION}" ./
 
-      - name: Upload Chart to ChartMuseum
+      - uses: docker/login-action@v3.7.0
+        with:
+          registry: ${{ github.server_url }}
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GIT_CRYPTIC_SYSTEMS_PACKAGE_REGISTRY_TOKEN }}
+
+      - name: Upload Chart to Gitea (OCI)
         env:
+          COSIGN_PASSWORD: ${{ secrets.COSIGN_PASSWORD }}
+          COSIGN_PRIVATE_KEY: ${{ secrets.COSIGN_PRIVATE_KEY }}
+        run: |
+          helm push ${REPOSITORY_NAME}-${PACKAGE_VERSION}.tgz oci://${GITEA_SERVER_HOSTNAME}/${REPOSITORY_OWNER}
+          cosign sign --yes --upload=true --key=env://COSIGN_PRIVATE_KEY ${GITEA_SERVER_HOSTNAME}/${REPOSITORY_OWNER}/${REPOSITORY_NAME}:${PACKAGE_VERSION}
+
+      - name: Upload Chart to Gitea (Helm)
+        env:
+          GITEA_REGISTRY_TOKEN: ${{ secrets.GIT_CRYPTIC_SYSTEMS_PACKAGE_REGISTRY_TOKEN }}
+        run: |
+          curl \
+            --fail \
+            --show-error \
+            --request POST \
+            --user "${REPOSITORY_OWNER}:${GITEA_REGISTRY_TOKEN}" \
+            --upload-file "${REPOSITORY_NAME}-${PACKAGE_VERSION}.tgz" \
+              https://git.cryptic.systems/api/packages/${REPOSITORY_OWNER}/helm/api/charts
+
+      - name: Upload Chart to Chartmuseum (Helm)
+        env:
+          CHARTMUSEUM_HOSTNAME: ${{ vars.CHARTMUSEUM_HOSTNAME }}
+          CHARTMUSEUM_USERNAME: ${{ secrets.CHARTMUSEUM_USERNAME }}
           CHARTMUSEUM_PASSWORD: ${{ secrets.CHARTMUSEUM_PASSWORD }}
           CHARTMUSEUM_REPOSITORY: ${{ vars.CHARTMUSEUM_REPOSITORY }}
-          CHARTMUSEUM_USERNAME: ${{ secrets.CHARTMUSEUM_USERNAME }}
-          CHARTMUSEUM_HOSTNAME: ${{ vars.CHARTMUSEUM_HOSTNAME }}
         run: |
-          helm repo add --username ${CHARTMUSEUM_USERNAME} --password ${CHARTMUSEUM_PASSWORD} chartmuseum https://${CHARTMUSEUM_HOSTNAME}/${CHARTMUSEUM_REPOSITORY}
+          curl \
-          helm cm-push ${REPOSITORY_NAME}-${PACKAGE_VERSION}.tgz chartmuseum
+            --fail \
-          helm repo remove chartmuseum
+            --show-error \
-
+            --request POST \
-      - name: Upload Chart to Gitea
+            --user "${CHARTMUSEUM_USERNAME}:${CHARTMUSEUM_PASSWORD}" \
-        env:
+            --upload-file "${REPOSITORY_NAME}-${PACKAGE_VERSION}.tgz" \
-          GITEA_PACKAGE_REGISTRY_TOKEN: ${{ secrets.GIT_CRYPTIC_SYSTEMS_PACKAGE_REGISTRY_TOKEN }}
+              https://${CHARTMUSEUM_HOSTNAME}/api/${CHARTMUSEUM_REPOSITORY}/charts
-          GITEA_SERVER_URL: ${{ github.server_url }}
-        run: |
-          helm repo add --username ${REPOSITORY_OWNER} --password ${GITEA_PACKAGE_REGISTRY_TOKEN} gitea ${GITEA_SERVER_URL}/api/packages/${REPOSITORY_OWNER}/helm
-          helm cm-push ${REPOSITORY_NAME}-${PACKAGE_VERSION}.tgz gitea
-          helm repo remove gitea

.gitignore

@@ -1,4 +1,5 @@
 charts
+cosign*
 node_modules
 target
 values2.yml

Chart.yaml

@@ -1,24 +1,25 @@
 annotations:
+  artifacthub.io/license: MIT
   artifacthub.io/links: |
     - name: Prometheus PostgreSQL exporter (binary)
       url: https://github.com/prometheus-community/postgres_exporter
     - name: support
       url: https://git.cryptic.systems/volker.raschek/prometheus-postgres-exporter/issues
+  artifacthub.io/operator: "false"
+  artifacthub.io/prerelease: "false"
 apiVersion: v2
-name: prometheus-postgres-exporter
-description: Prometheus metric exporter for PostgreSQL
-type: application
-version: "0.1.0"
 appVersion: "0.18.1"
-
+description: Prometheus metric exporter for PostgreSQL
+home: https://git.cryptic.systems/volker.raschek/prometheus-postgres-exporter
 # icon: https://annotations.example.com/icon.png
-
 keywords:
   - prometheus
   - prometheus-exporter
   - postgres-postgres-exporter
   - postgres-exporter
-
+name: prometheus-postgres-exporter
 sources:
   - https://github.com/prometheus-community/postgres_exporter
   - https://git.cryptic.systems/volker.raschek/prometheus-postgres-exporter
+type: application
+version: "0.1.0"

README.md

@@ -23,7 +23,8 @@ separate [chapter](#argocd).
 
 ## Helm: configuration and installation
 
-1. A helm chart repository must be configured, to pull the helm charts from.
+1. A helm chart repository must be configured, to pull the helm charts from. The helm charts can either be pulled from
+   the classic helm chart repository or OCI registry.
 2. All available [parameters](#parameters) are documented in detail below. The parameters can be defined via the helm
    `--set` flag or directly as part of a `values.yaml` file. The following example defines the `prometheus-exporter`
    repository and use the `--set` flag for a basic deployment.
@@ -34,7 +35,7 @@ separate [chapter](#argocd).
 > time is not possible.
 
 ```bash
-helm repo add prometheus-exporters https://charts.cryptic.systems/prometheus-exporters
+helm repo add prometheus-postgres-exporters https://git.cryptic.systems/prometheus-exporters
 helm repo update
 CHART_VERSION=0.5.5
 helm install --version "${CHART_VERSION}" prometheus-postgres-exporter prometheus-exporters/prometheus-postgres-exporter \
@@ -45,6 +46,18 @@ helm install --version "${CHART_VERSION}" prometheus-postgres-exporter prometheu
   --set 'prometheus.metrics.serviceMonitor.enabled=true'
 ```
 
+Alternatively, the deployment of the helm charts can also be done via an OCI registry:
+
+```bash
+CHART_VERSION=0.5.5
+helm install "oci://git.cryptic.systems/volker.raschek/prometheus-postgres-exporter:${CHART_VERSION}" \
+  --set 'config.database.secret.databaseUsername=postgres' \
+  --set 'config.database.secret.databasePassword=postgres' \
+  --set 'config.database.secret.databaseConnectionUrl="postgres.example.local:5432/postgres?ssl=disable"' \
+  --set 'prometheus.metrics.enabled=true' \
+  --set 'prometheus.metrics.serviceMonitor.enabled=true'
+```
+
 Instead of passing all parameters via the *set* flag, it is also possible to define them as part of the `values.yaml`.
 The following command downloads the `values.yaml` for a specific version of this chart. Please keep in mind, that the
 version of the chart must be in sync with the `values.yaml`. Newer *minor* versions can have new features. New *major*

artifacthub-repo.yml

@@ -0,0 +1 @@
+repositoryID: d4d5f778-e029-4401-81a3-29a0f689ee08