Add Helm Chart deployment and probes

Dockerfile

@@ -0,0 +1,25 @@
+# Build the manager binary
+FROM golang:1.17 as builder
+
+WORKDIR /workspace
+# Copy the Go Modules manifests
+COPY go.mod go.mod
+COPY go.sum go.sum
+# cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN go mod download
+
+# Copy the go source
+COPY . .
+
+# Build
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GO111MODULE=on go build -a -o cloudflare-ddns main.go
+
+# Use distroless as minimal base image to package the manager binary
+# Refer to https://github.com/GoogleContainerTools/distroless for more details
+FROM gcr.io/distroless/static:nonroot
+WORKDIR /
+COPY --from=builder /workspace/cloudflare-ddns .
+USER 65532:65532
+
+ENTRYPOINT ["/cloudflare-ddns"]

README.md

@@ -18,8 +18,9 @@ You can specify your configuration by means of a super simple `yaml` configurati
 - [ ] Allow DNS records to be created if not present already
 - [ ] Update DNS records concurrently instead of one after the other
 - [x] Logging & error handling
-- [ ] Allow configuring which DNS record to update manually
+- [x] Allow configuring which DNS records to update manually
 - [ ] CLI flags
-- [ ] Docker deployment
-- [ ] Kubernetes Helm Chart deployment
+- [ ] Docker Compose deployment
+- [x] Kubernetes Helm Chart deployment
+- [x] Readiness/liveness probes
 - [ ] API key and account email auth option

charts/cloudflare-ddns/.helmignore

@@ -0,0 +1,23 @@
+# Patterns to ignore when building packages.
+# This supports shell glob matching, relative path matching, and
+# negation (prefixed with !). Only one pattern per line.
+.DS_Store
+# Common VCS dirs
+.git/
+.gitignore
+.bzr/
+.bzrignore
+.hg/
+.hgignore
+.svn/
+# Common backup files
+*.swp
+*.bak
+*.tmp
+*.orig
+*~
+# Various IDEs
+.project
+.idea/
+*.tmproj
+.vscode/

charts/cloudflare-ddns/Chart.yaml

@@ -0,0 +1,24 @@
+apiVersion: v2
+name: cloudflare-ddns
+description: A Dynamic DNS for Cloudflare that allows your zones to be constantly up-to-date with your constantly changing public IP.
+
+# A chart can be either an 'application' or a 'library' chart.
+#
+# Application charts are a collection of templates that can be packaged into versioned archives
+# to be deployed.
+#
+# Library charts provide useful utilities or functions for the chart developer. They're included as
+# a dependency of application charts to inject those utilities and functions into the rendering
+# pipeline. Library charts do not define any templates and therefore cannot be deployed.
+type: application
+
+# This is the chart version. This version number should be incremented each time you make changes
+# to the chart and its templates, including the app version.
+# Versions are expected to follow Semantic Versioning (https://semver.org/)
+version: 0.1.0
+
+# This is the version number of the application being deployed. This version number should be
+# incremented each time you make changes to the application. Versions are not expected to
+# follow Semantic Versioning. They should reflect the version the application is using.
+# It is recommended to use it with quotes.
+appVersion: "0.1.0"

charts/cloudflare-ddns/templates/NOTES.txt

@@ -0,0 +1 @@
+Done.

charts/cloudflare-ddns/templates/_helpers.tpl

@@ -0,0 +1,62 @@
+{{/*
+Expand the name of the chart.
+*/}}
+{{- define "cloudflare-ddns.name" -}}
+{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Create a default fully qualified app name.
+We truncate at 63 chars because some Kubernetes name fields are limited to this (by the DNS naming spec).
+If release name contains chart name it will be used as a full name.
+*/}}
+{{- define "cloudflare-ddns.fullname" -}}
+{{- if .Values.fullnameOverride }}
+{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- $name := default .Chart.Name .Values.nameOverride }}
+{{- if contains $name .Release.Name }}
+{{- .Release.Name | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }}
+{{- end }}
+{{- end }}
+{{- end }}
+
+{{/*
+Create chart name and version as used by the chart label.
+*/}}
+{{- define "cloudflare-ddns.chart" -}}
+{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Common labels
+*/}}
+{{- define "cloudflare-ddns.labels" -}}
+helm.sh/chart: {{ include "cloudflare-ddns.chart" . }}
+{{ include "cloudflare-ddns.selectorLabels" . }}
+{{- if .Chart.AppVersion }}
+app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+{{- end }}
+app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end }}
+
+{{/*
+Selector labels
+*/}}
+{{- define "cloudflare-ddns.selectorLabels" -}}
+app.kubernetes.io/name: {{ include "cloudflare-ddns.name" . }}
+app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end }}
+
+{{/*
+Create the name of the service account to use
+*/}}
+{{- define "cloudflare-ddns.serviceAccountName" -}}
+{{- if .Values.serviceAccount.create }}
+{{- default (include "cloudflare-ddns.fullname" .) .Values.serviceAccount.name }}
+{{- else }}
+{{- default "default" .Values.serviceAccount.name }}
+{{- end }}
+{{- end }}

charts/cloudflare-ddns/templates/configmap.yaml

@@ -0,0 +1,10 @@
+apiVersion: v1
+data:
+  config.yaml: |-
+    {{ .Values.config | toYaml | indent 4 | trim }}
+kind: ConfigMap
+metadata:
+  name: config
+  namespace: {{ .Release.Namespace }}
+  labels:
+    {{- include "cloudflare-ddns.labels" . | nindent 4 }}

charts/cloudflare-ddns/templates/deployment.yaml

@@ -0,0 +1,67 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "cloudflare-ddns.fullname" . }}
+  labels:
+    {{- include "cloudflare-ddns.labels" . | nindent 4 }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  selector:
+    matchLabels:
+      {{- include "cloudflare-ddns.selectorLabels" . | nindent 6 }}
+  template:
+    metadata:
+      {{- with .Values.podAnnotations }}
+      annotations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      labels:
+        {{- include "cloudflare-ddns.selectorLabels" . | nindent 8 }}
+    spec:
+      {{- with .Values.imagePullSecrets }}
+      imagePullSecrets:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      serviceAccountName: {{ include "cloudflare-ddns.serviceAccountName" . }}
+      securityContext:
+        {{- toYaml .Values.podSecurityContext | nindent 8 }}
+      containers:
+        - name: {{ .Chart.Name }}
+          securityContext:
+            {{- toYaml .Values.securityContext | nindent 12 }}
+          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          livenessProbe:
+            httpGet:
+              path: /live
+              port: 8086
+            initialDelaySeconds: 5
+            periodSeconds: 5
+          readinessProbe:
+            httpGet:
+              path: /ready
+              port: 8086
+            periodSeconds: 5
+          resources:
+            {{- toYaml .Values.resources | nindent 12 }}
+          volumeMounts:
+            - mountPath: /config.yaml
+              name: config-volume
+              subPath: config.yaml
+      volumes:
+        - name: config-volume
+          configMap:
+            name: config
+
+      {{- with .Values.nodeSelector }}
+      nodeSelector:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.affinity }}
+      affinity:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.tolerations }}
+      tolerations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}

charts/cloudflare-ddns/templates/serviceaccount.yaml

@@ -0,0 +1,12 @@
+{{- if .Values.serviceAccount.create -}}
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: {{ include "cloudflare-ddns.serviceAccountName" . }}
+  labels:
+    {{- include "cloudflare-ddns.labels" . | nindent 4 }}
+  {{- with .Values.serviceAccount.annotations }}
+  annotations:
+    {{- toYaml . | nindent 4 }}
+  {{- end }}
+{{- end }}

charts/cloudflare-ddns/values.yaml

@@ -0,0 +1,68 @@
+# Default values for cloudflare-ddns.
+# This is a YAML-formatted file.
+# Declare variables to be passed into your templates.
+
+replicaCount: 1
+
+image:
+  repository: criscola/cloudflare-ddns
+  pullPolicy: IfNotPresent
+  # Overrides the image tag whose default is the chart appVersion.
+  tag: ""
+
+imagePullSecrets: []
+nameOverride: ""
+fullnameOverride: ""
+
+serviceAccount:
+  # Specifies whether a service account should be created
+  create: true
+  # Annotations to add to the service account
+  annotations: {}
+  # The name of the service account to use.
+  # If not set and create is true, a name is generated using the fullname template
+  name: ""
+
+podAnnotations: {}
+
+podSecurityContext: {}
+  # fsGroup: 2000
+
+securityContext: {}
+  # capabilities:
+  #   drop:
+  #   - ALL
+  # readOnlyRootFilesystem: true
+  # runAsNonRoot: true
+  # runAsUser: 1000
+
+resources: {}
+  # We usually recommend not to specify default resources and to leave this as a conscious
+  # choice for the user. This also increases chances charts run on environments with little
+  # resources, such as Minikube. If you do want to specify resources, uncomment the following
+  # lines, adjust them as necessary, and remove the curly braces after 'resources:'.
+  # limits:
+  #   cpu: 100m
+  #   memory: 128Mi
+  # requests:
+  #   cpu: 100m
+  #   memory: 128Mi
+
+nodeSelector: {}
+
+tolerations: []
+
+affinity: {}
+
+config:
+api_token: "your api token with Edit DNS enabled"
+refresh_interval: 60
+zones:
+  - zone_id: "your zone id"
+    proxied: true
+    ipv6: false
+  - zone_id: "your zone id"
+    ipv6: false
+    explicit_records: # pro-tip: use CNAME records if possible
+      - name: ""
+      - name: "ssh"

cmd/root.go

@@ -1,16 +1,19 @@
 /*
-Copyright © 2022 NAME HERE <EMAIL ADDRESS>
+Copyright © 2022 Cristiano Colangelo (criscola)
 
 */
 package cmd
 
 import (
 	"context"
+	"fmt"
 	"github.com/cloudflare/cloudflare-go"
 	"github.com/criscola/cloudflare-ddns/ddns"
+	"github.com/heptiolabs/healthcheck"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 	"go.uber.org/zap"
+	"net/http"
 	"os"
 )
 
@@ -41,10 +44,10 @@ func Execute() {
 }
 
 func init() {
-	// init logger
 	initLogger()
 	initConfig()
 	initClient()
+	initProbes()
 
 	// TODO: CLI Flags e.g. debug mode
 	// rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cloudflare-ddns.yaml)")
@@ -58,7 +61,7 @@ func initLogger() {
 func initConfig() {
 	viper.SetConfigName("config")                 // name of config file (without extension)
 	viper.SetConfigType("yaml")                   // REQUIRED if the config file does not have the extension in the name
-	viper.AddConfigPath("/etc/cloudflare-ddns/")  // path to look for the config file in
+	viper.AddConfigPath("/etc/cloudflare-ddns")   // path to look for the config file in
 	viper.AddConfigPath("$HOME/.cloudflare-ddns") // call multiple times to add many search paths
 	viper.AddConfigPath(".")                      // optionally look for config in the working directory
 	// TODO: Error handling, config validation, dependency injection
@@ -92,3 +95,27 @@ func initClient() {
 	}
 	logger.Debug("cfClient initialized successfully")
 }
+
+func initProbes() {
+	health := healthcheck.NewHandler()
+	// If app cannot reach 1.1.1.1, readiness probe will fail
+	checkPublicIpResolver := func() error {
+		resp, err := http.Get(ddns.PublicIpPage)
+		if err != nil {
+			return err
+		}
+		if resp.StatusCode < 200 || resp.StatusCode > 299 {
+			return fmt.Errorf("public IP resolver (%s) returned status code %d",
+				ddns.PublicIpPage, resp.StatusCode)
+		}
+		return nil
+	}
+	health.AddReadinessCheck("public-ip-resolver-webpage", checkPublicIpResolver)
+	go func() {
+		err := http.ListenAndServe("0.0.0.0:8086", health)
+		if err != nil {
+			logger.Fatalf("cannot start webserver on port 8086")
+		}
+		logger.Debug("probes started successfully")
+	}()
+}