add webhook

README.md

@@ -7,8 +7,9 @@ What can I do with this? Simply put: It will export any traefik labels on a cont
 
 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, ...).
 
+This image provides the ability to call a webhook for each container for each event or poll after the data was updates in Redis.
+
 ## 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 \
@@ -16,6 +17,15 @@ docker run --name traefik-labels \
   -d 11notes/traefik-labels:[tag]
 ```
 
+```shell
+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]
+```
+
 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 \
@@ -40,8 +50,10 @@ docker run --name demo \
 | Parameter | Value | Default |
 | --- | --- | --- |
 | `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 |  |
 
 ## Parent image
 * [11notes/node:stable](https://github.com/11notes/docker-node)

rootfs/labels/app.js

@@ -8,7 +8,7 @@ class Labels{
   #poll = false;
 
   constructor(){
-    this.#docker = new Docker({socketPath: '/run/docker.sock'});
+    this.#docker = new Docker({socketPath:'/run/docker.sock'});
   }
 
   #log(message, error){
@@ -20,6 +20,10 @@ class Labels{
   }
 
   async watch(){
+    if('' !== process.env.LABELS_WEBHOOK){
+      this.#log(`using webhook ${process.env.LABELS_WEBHOOK}`);
+    }
+
     this.#redis = await redis.createClient({
       url:process.env.LABELS_REDIS_URL,
       pingInterval:30000,
@@ -82,31 +86,48 @@ class Labels{
 
   dockerInspect(id, status = null){
     return(new Promise((resolve, reject) => {
-      let log = false;
       const container = this.#docker.getContainer(id);
       container.inspect(async(error, data) => {
+
+        let update = false;
+        const webHook = {event:status, labels:{}}; 
+        const headers = {'Content-Type':'application/json'};
+
+        if('' !== process.env.LABELS_WEBHOOK_AUTH_BASIC){
+          headers['Authorization'] = 'Basic ' + Buffer.from(process.env.LABELS_WEBHOOK_AUTH_BASIC).toString('base64')
+        }
+
         if(error){
           reject(error);
         }
+
+        this.#log(`inspect container ${data.Name.replace(/^\//i, '')}${(
+          (null === status) ? '' : ` event[${status}]`
+        )}`);
+
+        if(/start|restart/i.test(status)){
+          update = true;
+        }
+     
         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;
+            webHook.labels[label] = data?.Config?.Labels[label];
+            if(update){
+              await this.#redis.set(label, data?.Config?.Labels[label], {EX:parseInt(process.env.LABELS_INTERVAL) + parseInt(process.env.LABELS_TIMEOUT)});
+            }else{
+              await this.#redis.del(label);
             }
           }
         }
+        if('' !== process.env.LABELS_WEBHOOK){
+          try{
+            const webHookCall = await fetch(process.env.LABELS_WEBHOOK, {method:(
+              (update) ? 'PUT' : 'DELETE'
+            ), body:JSON.stringify(webHook), headers:headers});
+          }catch(e){
+            this.#log(e, ERROR);
+          }
+        }
         resolve(true);
       });
     }));

rootfs/labels/main.js

@@ -6,6 +6,8 @@ const child = fork(`${__dirname}/app.js`, [], {
     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),
+    LABELS_WEBHOOK:process.env?.LABELS_WEBHOOK || '',
+    LABELS_WEBHOOK_AUTH_BASIC:process.env?.LABELS_WEBHOOK_AUTH_BASIC || '',
   }
 });
 child.on('error', (error) =>{