exception handling

.gitignore

@@ -1,2 +1 @@
-maintain/
-/build
+maintain/

README.md

@@ -1,14 +1,19 @@
 # Alpine :: Traefik Labels
-![size](https://img.shields.io/docker/image-size/11notes/traefik-labels/0.1.3?color=0eb305) ![version](https://img.shields.io/docker/v/11notes/traefik-labels?color=eb7a09) ![pulls](https://img.shields.io/docker/pulls/11notes/traefik-labels?color=2b75d6) ![activity](https://img.shields.io/github/commit-activity/m/11notes/docker-traefik-labels?color=c91cb8) ![commit-last](https://img.shields.io/github/last-commit/11notes/docker-traefik-labels?color=c91cb8)
+![size](https://img.shields.io/docker/image-size/11notes/traefik-labels/amd64-0.1.10?color=0eb305) ![version](https://img.shields.io/docker/v/11notes/traefik-labels/amd64-0.1.10?color=eb7a09) ![pulls](https://img.shields.io/docker/pulls/11notes/traefik-labels?color=2b75d6) ![activity](https://img.shields.io/github/commit-activity/m/11notes/docker-traefik-labels?color=c91cb8) ![commit-last](https://img.shields.io/github/last-commit/11notes/docker-traefik-labels?color=c91cb8)
 
 Run Traefik Labels based on Alpine Linux. Small, lightweight, secure and fast 🏔️
 
-What can I do with this? Simply put: It will export any traefik labels on a container on the same host as this image runs to a Redis instance. This makes it possible for a centralized Traefik load balancer to update endpoints dynamically by utilizing the docker labels, just like you would on a local installation of Traefik with labels. It is meant as an alternative and simple way to proxy requests from a Traefik load balanacer to multiple docker nodes running in different networks and locations.
+## Description
+What can I do with this? Simply put: It will export any traefik labels on a container on the same host as this image runs to a Redis instance. This makes it possible for a centralized Traefik load balancer to update endpoints dynamically by utilizing the docker labels, just like you would on a local installation of Traefik with labels. It is meant as an alternative and simple way to proxy requests from a Traefik load balancer to multiple docker nodes running in different networks and locations. The image has the ability to use nsupdate with labels too, so that not only you can add a dynamic proxy to your Traefik, but add DNS entries to your internal or external NS servers. It uses split DNS as WAN and LAN in your labels, so you can update external as well as internal DNS entries on the fly. If a container is removed the image will automatically reverse any `nsupdate update add` to `nsupdate update delete` so entrie are removed too.
 
-In order to use this image, you need to setup Traefik with a Redis provider and then point this image via REDIS_URL to the same Redis instance. Each entry will have an expire timer set in Redis, so that if a container is removed by a server crashing, Redis will automatically remove stale entries as well. Entries are refreshed every 60 seconds or on all docker container events (create, run, kill, stop, restart, ...).
+In order to use this image, you need to setup Traefik with a Redis provider and then point this image via REDIS_URL to the same Redis instance. Each entry will have an expire timer set in Redis, so that if a container is removed by a server crashing, Redis will automatically remove stale entries as well. Entries are refreshed every 300 seconds or on all docker container events (create, run, kill, stop, restart, ...). As for nsupdate, you need to setup tsig authentication in your NS servers and add the keys to the zones you want to be able to update, you can restrict the keys by using update-policy if you use BIND.
+
+This image provides the ability to call a webhook for each container for each event or poll after the data was updates in Redis and or nsupdate.
+
+## Volumes
+* **/labels/ssl** - Directory of ssl certificates for TLS<sup>1</sup>
 
 ## Run
-This will export all labels from all containers to the Redis instance specified in LABELS_REDIS_URL from the same host this container is running on.
 ```shell
 docker run --name traefik-labels \
   -v /run/docker.sock:/run/docker.sock \
@@ -16,9 +21,27 @@ docker run --name traefik-labels \
   -d 11notes/traefik-labels:[tag]
 ```
 
-This is a demo webserver that will start on :8080, all the traefik labels will be exportet to the Redis instance. They follow the exact same [syntax](https://doc.traefik.io/traefik/routing/providers/kv/) as for normal Redis and Traefik, just as labels.
 ```shell
-docker run --name demo \
+docker run --name traefik-labels \
+  -v /run/docker.sock:/run/docker.sock \
+  -e LABELS_REDIS_URL="rediss://foo:bar@10.127.198.254:6379/0" \
+  -e LABELS_WEBHOOK="https://domain.com/traefik/labels" \
+  -e LABELS_WEBHOOK_AUTH_BASIC="foo:bar" \
+  -d 11notes/traefik-labels:[tag]
+```
+
+```shell
+docker run --name traefik-labels \
+  -v .../ssl:/labels/ssl \
+  -e LABELS_REDIS_URL="rediss://foo:bar@10.127.198.254:6379/0" \
+  -e LABELS_WEBHOOK="https://domain.com/traefik/labels" \
+  -e LABELS_WEBHOOK_AUTH_BASIC="foo:bar" \
+  -d 11notes/traefik-labels:[tag]
+```
+
+## Examples
+```shell
+docker run --name traefik-demo \
   -p 8080:8080 \
   -l "traefik/http/routers/demo.domain.com/service=demo.domain.com" \
   -l "traefik/http/routers/demo.domain.com/rule=Host(`demo.domain.com`)" \
@@ -28,6 +51,24 @@ docker run --name demo \
   -d 11notes/nginx:stable
 ```
 
+```shell
+docker run --name traefik-rfc2136-demo \
+  -p 8080:8080 \
+  -l "traefik/http/routers/demo.domain.com/service=demo.domain.com" \
+  -l "traefik/http/routers/demo.domain.com/rule=Host(`demo.domain.com`)" \
+  -l "traefik/http/routers/demo.domain.com/tls=true" \
+  -l "traefik/http/routers/demo.domain.com/entrypoints=https" \
+  -l "traefik/http/services/demo.domain.com/loadbalancer/servers/0/url=http://fqdn-of-docker-node:8080" \
+  -l "rfc2136/WAN/server=ns.domain.com" \
+  -l "rfc2136/WAN/key=algo:name:secret" \
+  -l "rfc2136/WAN/nsupdate=update add foo.domain.com 300 A 175.12.41.11" \
+  -l "rfc2136/WAN/nsupdate=update add foo.domain.com 300 TXT \"hello from traefik-labels!\"" \
+  -l "rfc2136/LAN/server=ns.domain.local" \
+  -l "rfc2136/LAN/key=algo:name:secret" \
+  -l "rfc2136/LAN/nsupdate=update add foo.domain.local 300 A 192.168.12.54" \
+  -d 11notes/nginx:stable
+```
+
 ## Defaults
 | Parameter | Value | Description |
 | --- | --- | --- |
@@ -35,18 +76,29 @@ docker run --name demo \
 | `uid` | 1000 | user id 1000 |
 | `gid` | 1000 | group id 1000 |
 | `home` | /labels | home directory of user docker |
+| `api` | https://${IP}:5000 | HTTPS endpoint of Docker registry |
+| `ca.crt` | /labels/ssl/ca.crt | Certificate of CA for TLS<sup>1</sup> |
+| `labels.crt` | /labels/ssl/labels.crt | Certificate of client for TLS<sup>1</sup> |
+| `labels.key` | /labels/ssl/labels.key | Private key of client for TLS<sup>1</sup> |
 
 ## Environment
 | Parameter | Value | Default |
 | --- | --- | --- |
+| `TZ` | [Time Zone](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones) | |
+| `DEBUG` | Show debug information | |
 | `LABELS_REDIS_URL` | the redis URL to connect, use rediss:// for SSL | rediss://localhost:6379/0 |
-| `LABELS_INTERVAL` | in what interval container information is pulled | 300 |
-| `LABELS_TIMEOUT` | how many seconds after an interval the keys should stay till they expire | 30 |
+| `LABELS_INTERVAL` | in what interval container information is pulled in seconds | 300 |
+| `LABELS_TIMEOUT` | how many seconds after an interval the keys should stay till they expire in seconds | 30 |
+| `LABELS_WEBHOOK` | URL to call on each event or poll for each container |  |
+| `LABELS_WEBHOOK_AUTH_BASIC` | Basic authentication to use in the form of "username:password" for the webhook |  |
+| `LABELS_RFC2136_ONLY_UPDATE_ON_CHANGE` | Only update DNS entries if they are new or changed (will use dig on each call to the set server) |  |
+| `LABELS_DOCKER_IP` | Used for TLS<sup>1</sup> authentication against dockerd | localhost |
+| `LABELS_DOCKER_PORT` | Used for TLS<sup>1</sup> authentication against dockerd | 2376 |
 
 ## Parent image
-* [11notes/node:stable](https://github.com/11notes/docker-node)
+* [11notes/node:stable](https://hub.docker.com/r/11notes/node)
 
-## Built with and thanks to
+## Built with (thanks to)
 * [npm::redis](https://www.npmjs.com/package/redis)
 * [npm::dockerode](https://www.npmjs.com/package/dockerode)
 * [nodejs](https://nodejs.org/en)
@@ -55,4 +107,18 @@ docker run --name demo \
 ## Tips
 * Only use rootless container runtime (podman, rootless docker)
 * Don't bind to ports < 1024 (requires root), use NAT/reverse proxy (haproxy, traefik, nginx)
-* Do not access docker.sock as root
+* Do not access docker.sock as root
+* Use TLS if you can't access docker.sock as non-root
+
+## Disclaimers
+* <sup>1</sup> For TLS to work you need proper certificates in place for your dockerd and your clients. The CN in the certificate needs to match the FQDN or IP you have set on the docker node, you can set multiple by using SAN. See an example of a daemon.json configuration to enable TLS.
+```json
+{
+  "tls": true,
+  "tlsverify": true,
+  "tlscacert": "/etc/docker/ca.crt",
+  "tlscert": "/etc/docker/server.crt",
+  "tlskey": "/etc/docker/server.key",
+  "hosts": ["unix:///var/run/docker.sock", "tcp://0.0.0.0:2376"]
+}
+```

amd64.dockerfile

@@ -1,3 +1,11 @@
+# :: Util
+  FROM alpine as util
+
+  RUN set -ex; \
+    apk add --no-cache \
+      git; \
+    git clone https://github.com/11notes/util.git;
+
 # :: Header
   FROM 11notes/node:stable
   ENV APP_ROOT=/labels
@@ -7,13 +15,19 @@
 
   # :: prepare image
     RUN set -ex; \
-      mkdir -p ${APP_ROOT};
+      mkdir -p ${APP_ROOT}/lib; \
+      apk --no-cache add \
+        bind-tools; \
+      apk --no-cache upgrade;
+
+    COPY --from=util /util/node/util.js /labels/lib
 
   # :: install
     RUN set -ex; \
       cd ${APP_ROOT}; \
       npm --save install \
         redis@4.6.11 \
+        js-yaml@4.1.0 \
         dockerode@4.0.0;
 
   # :: update image

arm64v8.dockerfile

@@ -0,0 +1,52 @@
+# :: Util
+  FROM alpine as util
+
+  RUN set -ex; \
+    apk add --no-cache \
+      git; \
+    git clone https://github.com/11notes/util.git;
+
+# :: Builder
+  FROM alpine AS qemu
+  ENV QEMU_URL https://github.com/balena-io/qemu/releases/download/v3.0.0%2Bresin/qemu-3.0.0+resin-aarch64.tar.gz
+  RUN apk add curl && curl -L ${QEMU_URL} | tar zxvf - -C . && mv qemu-3.0.0+resin-aarch64/qemu-aarch64-static .
+
+# :: Header
+  FROM arm64v8/node:20.10.0-alpine3.19
+  COPY --from=qemu qemu-aarch64-static /usr/bin
+  ENV APP_ROOT=/labels
+
+# :: Run
+  USER root
+
+  # :: prepare image
+    RUN set -ex; \
+      mkdir -p ${APP_ROOT}/lib; \
+      apk --no-cache add \
+        bind-tools; \
+      apk --no-cache upgrade;
+
+    COPY --from=util /util/node/util.js /labels/lib
+
+  # :: install
+    RUN set -ex; \
+      cd ${APP_ROOT}; \
+      npm --save install \
+        redis@4.6.11 \
+        js-yaml@4.1.0 \
+        dockerode@4.0.0;
+
+  # :: update image
+    RUN set -ex; \
+      apk --no-cache upgrade;
+
+  # :: copy root filesystem changes and set correct permissions
+    COPY ./rootfs /
+    RUN set -ex; \
+      chmod +x -R /usr/local/bin; \
+      chown -R 1000:1000 \
+        ${APP_ROOT};
+
+# :: Start
+  USER docker
+  ENTRYPOINT ["/usr/local/bin/entrypoint.sh"]

hooks/post_push

@@ -0,0 +1,4 @@
+#!/bin/bash
+curl -Lo manifest-tool https://github.com/estesp/manifest-tool/releases/download/v0.9.0/manifest-tool-linux-amd64
+chmod +x manifest-tool
+./manifest-tool push from-spec multi-arch-manifest.yaml

hooks/pre_build

@@ -0,0 +1,2 @@
+#!/bin/bash
+  docker run --rm --privileged multiarch/qemu-user-static:register --reset

multi-arch-manifest.yaml

@@ -0,0 +1,11 @@
+image: 11notes/traefik-labels:latest
+manifests:
+  - image: 11notes/traefik-labels:amd64-0.2.0
+    platform:
+      architecture: amd64
+      os: linux
+  - image: 11notes/traefik-labels:arm64v8-0.2.0
+    platform:
+      architecture: arm64
+      os: linux
+      variant: v8

rootfs/labels/app.js

@@ -1,116 +0,0 @@
-const Docker = require('dockerode');
-const redis = require('redis');
-const ERROR = 1;
-
-class Labels{
-  #docker;
-  #redis;
-  #poll = false;
-
-  constructor(){
-    this.#docker = new Docker({socketPath: '/run/docker.sock'});
-  }
-
-  #log(message, error){
-    console.log(JSON.stringify({
-      time:new Date().toISOString(),
-      type:(error === ERROR) ? 'ERROR' : 'INFO',
-      message:message,
-    }));
-  }
-
-  async watch(){
-    this.#redis = await redis.createClient({
-      url:process.env.LABELS_REDIS_URL,
-      pingInterval:30000,
-      socket:{
-        rejectUnauthorized: false,
-      }
-    });
-
-    this.#redis.connect();
-    this.#redis.on('ready', ()=>{
-      this.#log('successfully connected to redis database');
-      (async() => {
-        await this.dockerPoll();
-      })();
-      this.dockerEvents();
-    });
-
-    this.#redis.on('error', error =>{
-      this.#log(error, ERROR);
-    });
-
-    setInterval(async() => {
-      await this.dockerPoll();
-    }, parseInt(process.env.LABELS_INTERVAL)*1000);
-  }
-
-  dockerEvents(){
-    this.#docker.getEvents({}, (error, data) => {
-      if(error){
-        this.#log(error, ERROR);
-      }else{
-        data.on('data', async(chunk) => {
-          const event = JSON.parse(chunk.toString('utf8'));
-          if(/Container/i.test(event?.Type) && /^(start|stop|restart|kill|die|destroy)$/i.test(event?.status)){
-            await this.dockerInspect(event.id, event.status);
-          }
-        });
-      }
-    });
-  }
-
-  async dockerPoll(){
-    if(!this.#poll){
-      try{
-        this.#poll = true;
-        this.#log(`poll start (interval:${process.env.LABELS_INTERVAL})}`);
-        this.#docker.listContainers((error, containers) => {
-          containers.forEach(async(container) => {
-            await this.dockerInspect(container.Id);
-          });
-        });
-      }catch(e){
-        this.#log(e, ERROR);
-      }finally{
-        this.#log('poll end');
-        this.#poll = false;
-      }
-    }
-  }
-
-  dockerInspect(id, status = null){
-    return(new Promise((resolve, reject) => {
-      let log = false;
-      const container = this.#docker.getContainer(id);
-      container.inspect(async(error, data) => {
-        if(error){
-          reject(error);
-        }
-        for(const label in data?.Config?.Labels){
-          if(/traefik\//i.test(label)){
-            if(!log){
-              this.#log(`inspect container ${data.Name.replace(/^\//i, '')}${(
-                (null === status) ? '' : ` event[${status}]`
-              )}`);
-              log = true;
-            }
-            switch(true){
-              case /start|restart/i.test(status):
-                await this.#redis.set(label, data?.Config?.Labels[label], {EX:parseInt(process.env.LABELS_INTERVAL) + parseInt(process.env.LABELS_TIMEOUT)});
-              break;
-
-              case /stop|kill|die|destroy/i.test(status):
-                await this.#redis.del(label);
-              break;
-            }
-          }
-        }
-        resolve(true);
-      });
-    }));
-  }
-}
-
-new Labels().watch();

rootfs/labels/dig.js

@@ -0,0 +1,27 @@
+const { spawn } = require('node:child_process');
+const { elevenLogJSON } = require('/labels/lib/util.js');
+
+exports.dig = async(resolver, type, record) => {
+  return(new Promise((resolve, reject) => {
+    const dig = spawn('/usr/bin/dig', ['+short', '+answer', type, record, `@${resolver}`]);
+    const io = {stdout:'', stderr:''};
+    dig.stderr.on('data', data => {io.stderr += data.toString()});
+    dig.stdout.on('data', data => {io.stdout += (data.toString()).replace(/[\r\n]*$/ig, '')});
+    dig.on('error', error => {reject(error)});
+    dig.on('close', code =>{
+      elevenLogJSON('debug', {method:'dig()', params:{resolver:resolver, type:type, record:record}, io:io});
+      switch(true){
+        case /no servers could be reached/ig.test(io.stdout): io.stderr += io.stdout; break;
+      }
+      if(code === 0){
+        if(io.stderr.length > 0){
+          reject(io.stderr);
+        }else{
+          resolve(io.stdout);
+        }
+      }else{
+        reject(io.stderr);
+      }
+    });
+  }));
+}

rootfs/labels/etc/config.yaml

@@ -0,0 +1,20 @@
+labels:
+  redis:
+    url: rediss://foo:bar@10.127.198.254:6379/0
+  webhook:
+    url: https://my.cool.webhook/v1
+    auth:
+      basic: labels:*****
+  nodes:
+    - 192.168.18.12
+    - 10.14.120.1
+  rfc2136:
+    update-only: true
+  poll:
+    interval: 300
+  ping:
+    interval: 2.5
+  tls:
+    ca: /labels/ssl/ca.crt
+    crt: /labels/ssl/server.crt
+    key: /labels/ssl/server.key

rootfs/labels/main.js

@@ -1,18 +1,262 @@
-process.once('SIGTERM', () => process.exit(0));
-process.once('SIGINT', () => process.exit(0));
-const { fork } = require('node:child_process');
-const child = fork(`${__dirname}/app.js`, [], {
-  env:{
-    LABELS_REDIS_URL:process.env?.LABELS_REDIS_URL || 'rediss://localhost:6379/0',
-    LABELS_INTERVAL:parseInt(process.env?.LABELS_INTERVAL || 300),
-    LABELS_TIMEOUT:parseInt(process.env?.LABELS_TIMEOUT|| 30),
+const fs = require('fs');
+const util = require('util');
+const Docker = require('dockerode');
+const yaml = require('js-yaml');
+const redis = require('redis');
+const { nsupdate } = require('./nsupdate');
+const { dig } = require('./dig');
+const { elevenLogJSON } = require('/labels/lib/util.js');
+
+class Labels{
+  #config = yaml.load(fs.readFileSync(`${process.env.APP_ROOT}/etc/config.yaml`, 'utf8'))?.labels;
+  #defaults = {
+      tls:{
+        ca:`${process.env.APP_ROOT}/ssl/ca.crt`,
+        crt:`${process.env.APP_ROOT}/ssl/labels.crt`,
+        key:`${process.env.APP_ROOT}/ssl/labels.key`,
+        port:2376
+      },poll:{interval:300}, ping:{interval:2.5}, redis:{url:'rediss://localhost:6379/0'}, rfc2136:{'update-only':false}};
+  #intervals = {ping:false, poll:false};
+  #loops = {ping:false, poll:false};
+  #redis;
+  #nodes = {};
+
+  constructor(){
+    for(const node of this.#config?.nodes){
+      this.#nodes[node] = new Docker({
+        protocol:'https',
+        host:node,
+        port:this.#config?.tls?.port || this.#defaults.tls.port,
+        ca:fs.readFileSync(this.#config?.tls?.ca || this.#defaults.tls.ca),
+        cert:fs.readFileSync(this.#config?.tls?.crt || this.#defaults.tls.crt),
+        key:fs.readFileSync(this.#config?.tls?.key || this.#defaults.tls.key),
+      });
+      this.#nodes[node].labels = {ping:false, firstConnect:true};
+    }
+
+    if(this.#config?.webhook?.url){
+      this.#config.webhook.headers = {'Content-Type':'application/json'};
+      switch(true){
+        case this.#config?.webhook?.auth?.basic:
+          this.#config.webhook.headers['Authorization'] = 'Basic ' + Buffer.from(this.#config.webhook.auth.basic).toString('base64');
+          break;
+      }      
+    }
   }
-});
-child.on('error', (error) =>{
-  console.error(error);
-  process.exit(1);
-});
-child.on('close', (code) =>{
-  console.warn(`child process closed with exit code ${code}`);
-  process.exit(code);
-});
+
+  async watch(){  
+    this.#redis = await redis.createClient({
+      url:this.#config?.redis?.url || this.#defaults.redis.url,
+      pingInterval:30000,
+      socket:{
+        rejectUnauthorized: false,
+      }
+    });
+
+    this.#redis.on('ready', async()=>{
+      elevenLogJSON('info', `connected to redis`);
+      await this.#ping();
+      await this.#poll();
+    });
+
+    this.#redis.on('error', error =>{
+      elevenLogJSON('error', JSON.stringify({redis:{exception:e.toString()}}));
+    });
+
+    this.#redis.connect();
+  }
+
+  async #ping(){
+    if(!this.#intervals.ping){
+      this.#intervals.ping = true;
+      setInterval(async() => {
+        if(!this.#loops.ping){
+          this.#loops.ping = true;
+          try{
+            await this.#ping()
+          }catch(e){
+            elevenLogJSON('error', JSON.stringify({ping:{exception:e.toString()}}));
+          }finally{
+            this.#loops.ping = false;
+          }
+        }
+      }, (this.#config?.ping?.interval || this.#defaults.ping.interval)*1000);
+    }
+
+    for(const node in this.#nodes){
+      try{
+        await this.#nodes[node].ping();
+        if(!this.#nodes[node].labels.ping){
+          elevenLogJSON('info', `connected to node [${node}]`);
+          this.#nodes[node].getEvents({}, (error, data) => {
+            if(!error){
+              data.on('data', async(chunk) =>{
+                const event = JSON.parse(chunk.toString('utf8'));
+                if(/Container/i.test(event?.Type) && /^(start|die)$/i.test(event?.status)){
+                  await this.#inspect(node, event.id, event.status);
+                }
+              });
+            }else{
+              elevenLogJSON('error', JSON.stringify({getEvents:{exception:error.toString()}}));
+            }
+          });
+        }
+        this.#nodes[node].labels.ping = true;
+      }catch(e){
+        elevenLogJSON('error', JSON.stringify({ping:{exception:e.toString()}}));
+        if(this.#nodes[node].labels.ping){
+          elevenLogJSON('warning', `connection to node [${node}] lost!`);
+        }else if(this.#nodes[node].labels.firstConnect){
+          this.#nodes[node].labels.firstConnect = false;
+          elevenLogJSON('warning', `connection to node [${node}] failed!`);
+        }
+        this.#nodes[node].labels.ping = false;
+      }
+    }
+  }
+
+  async #poll(){
+    if(!this.#intervals.poll){
+      this.#intervals.poll = true;
+      setInterval(async() => {
+        if(!this.#loops.poll){
+          this.#loops.poll = true;
+          try{
+            await this.#poll()
+          }catch(e){
+            elevenLogJSON('error', JSON.stringify({poll:{exception:e.toString()}}));
+          }finally{
+            this.#loops.poll = false;
+          }
+        }
+      }, (this.#config?.poll?.interval || this.#defaults.poll.interval)*1000);
+    }
+
+    for(const node in this.#nodes){
+      try{
+        await this.#nodes[node].listContainers((error, containers) => {
+          if(!error){
+            containers.forEach(async(container) => {
+              await this.#inspect(node, container.Id, 'poll');
+            });
+          }
+        });
+      }catch(e){
+        elevenLogJSON('error', JSON.stringify({listContainers:{exception:e.toString()}}));
+      }
+    }
+  }
+
+  async #inspect(node, id, event){
+    return(new Promise((resolve, reject) => {
+      const container = this.#nodes[node].getContainer(id);
+      container.inspect(async(error, data) => {
+        if(!error){
+          const container = {
+            name:(data?.Name || data?.id).replace(/^\//i, ''),
+            event:event,
+            run:(/start|poll/i.test(event)) ? true : false,
+            labels:{
+              traefik:[],
+              rfc2136:[],
+            },
+          };
+
+          elevenLogJSON('info', `[${node}] container [${container.name}] event [${container.event}]`);
+
+          const rfc2136 = {
+            WAN:{server:'', key:'', commands:[]},
+            LAN:{server:'', key:'', commands:[]},
+          }
+          
+          for(const label in data?.Config?.Labels){
+            switch(true){
+              case /traefik\//i.test(label):
+                if(container.run){
+                  await this.#redis.set(label, data.Config.Labels[label], {EX:(this.#config?.poll?.interval || this.#defaults.poll.interval) + 30});
+                }else{
+                  await this.#redis.del(label);
+                }
+                container.labels.traefik[label] = data.Config.Labels[label];
+              break;
+
+              case /rfc2136\//i.test(label):
+                container.labels.rfc2136[label] = data.Config.Labels[label];
+                const type = ((label.match(/rfc2136\/WAN\//i)) ? 'WAN' : 'LAN');
+                switch(true){
+                  case /rfc2136\/\S+\/server/i.test(label):
+                    rfc2136[type].server = data.Config.Labels[label];
+                  break;
+
+                  case /rfc2136\/\S+\/key/i.test(label):
+                    rfc2136[type].key = data.Config.Labels[label];
+                  break;
+
+                  default:
+                    if(!container.run){
+                      data.Config.Labels[label] = data.Config.Labels[label].replace(/update add/i, 'update delete');
+                    }
+                    rfc2136[type].commands.push(data.Config.Labels[label]);
+                }
+              break;
+            }
+          }
+
+          if(rfc2136.LAN.commands.length > 0 || rfc2136.WAN.commands.length){
+            await this.#rfc2136(rfc2136);
+          }
+
+          if(this.#config?.webhook?.url){
+            await this.#webhook(container);
+          }
+        }
+      })
+      resolve(true);
+    }));
+  }
+
+  async #rfc2136(rfc2136){
+    for(const type in rfc2136){
+      if(rfc2136[type].commands.length > 0 && rfc2136[type].server && rfc2136[type].key){
+        if(this.#config?.rfc2136?.['update-only'] || this.#defaults?.rfc2136?.['update-only']){
+          for(let i=0; i<rfc2136[type].commands.length; i++){
+            if(await this.#rfc2136knownRecord(rfc2136[type].server, rfc2136[type].commands[i])){
+              rfc2136[type].commands.splice(i, 1);
+            }
+          }
+        }
+        try{
+          if(rfc2136[type].commands.length > 0){
+            await nsupdate(rfc2136[type].server, rfc2136[type].key, rfc2136[type].commands);
+          }
+        }catch(e){
+          elevenLogJSON('error', JSON.stringify({nsupdate:{exception:e.toString()}}));
+        }
+      }
+    }
+  }
+
+  async #rfc2136knownRecord(server, nsupdate){
+    const matches = nsupdate.match(/update add (\S+) \d+ (\S+) (\S+)/i);
+    if(matches && matches.length >= 4){
+      try{
+        const record = await dig(server, matches[2], matches[1]);
+        return((record.match(new RegExp(matches[3], 'ig'))));
+      }catch(e){
+        return(false);
+      }
+    }    
+  }
+
+  async #webhook(container){
+    try{
+      await fetch(this.#config.webhook.url, {method:(
+        (container.run) ? 'PUT' : 'DELETE'
+      ), body:JSON.stringify(container), headers:this.#config.webhook.headers, signal:AbortSignal.timeout(2500)});
+    }catch(e){
+      elevenLogJSON('error', JSON.stringify({webhook:{exception:e.toString()}}));
+    }
+  }
+}
+
+new Labels().watch();

rootfs/labels/nsupdate.js

@@ -0,0 +1,33 @@
+const { spawn } = require('node:child_process');
+const { elevenLogJSON } = require('/labels/lib/util.js');
+
+exports.nsupdate = async(server, key, commands) => {
+
+  commands.unshift(`server ${server}`);
+  commands.push('send');
+  commands.push('quit');
+
+  return(new Promise((resolve, reject) => {
+    elevenLogJSON('debug', {method:'nsupdate()', params:{server:server, key:'******', commands:commands}});
+    const nsupdate = spawn('/usr/bin/nsupdate', ['-y', key]);
+    const io = {stdout:'', stderr:''};
+    nsupdate.stderr.on('data', data => {io.stderr += data.toString()});
+    nsupdate.stdout.on('data', data => {io.stdout += (data.toString()).replace(/[\r\n]*$/ig, '')});
+    nsupdate.on('error', error => {reject(error)});
+    nsupdate.on('close', code =>{
+      if(code === 0){
+        if(io.stderr.length > 0){
+          reject(io.stderr);
+        }else{
+          resolve(io.stdout);
+        }
+      }else{
+        reject(io.stderr);
+      }
+    });
+    for(const command of commands){
+      nsupdate.stdin.write(`${command}\n`);
+    }
+    nsupdate.stdin.end();
+  }));
+}