Option to disable puppeteer in unfurler

unfurler/config.sample.json

@@ -9,6 +9,7 @@
     "NETWORK": "bitcoin" // "bitcoin" | "liquid" | "bisq" (optional - defaults to "bitcoin")
   },
   "PUPPETEER": {
+    "DISABLE": false, // optional, boolean, disables puppeteer and /render endpoints
     "CLUSTER_SIZE": 2,
     "EXEC_PATH": "/usr/local/bin/chrome", // optional
     "MAX_PAGE_AGE": 86400, // maximum lifetime of a page session (in seconds)

unfurler/src/config.ts

@@ -11,6 +11,7 @@ interface IConfig {
     NETWORK?: string;
   };
   PUPPETEER: {
+    DISABLE: boolean;
     CLUSTER_SIZE: number;
     EXEC_PATH?: string;
     MAX_PAGE_AGE?: number;
@@ -28,6 +29,7 @@ const defaults: IConfig = {
     'HTTP_PORT': 4200,
   },
   'PUPPETEER': {
+    'DISABLE': false,
     'CLUSTER_SIZE': 1,
   },
 };

unfurler/src/index.ts

@@ -37,12 +37,14 @@ class Server {
       .use(express.text())
       ;
 
+    if (!config.PUPPETEER.DISABLE) {
       this.cluster = await Cluster.launch({
           concurrency: ReusablePage,
           maxConcurrency: config.PUPPETEER.CLUSTER_SIZE,
           puppeteerOptions: puppeteerConfig,
       });
       await this.cluster?.task(async (args) => { return this.clusterTask(args) });
+    }
 
     this.setUpRoutes();
 
@@ -64,7 +66,11 @@ class Server {
   }
 
   setUpRoutes() {
+    if (!config.PUPPETEER.DISABLE) {
       this.app.get('/render*', async (req, res) => { return this.renderPreview(req, res) })
+    } else {
+      this.app.get('/render*', async (req, res) => { return this.renderDisabled(req, res) })
+    }
     this.app.get('*', (req, res) => { return this.renderHTML(req, res) })
   }
 
@@ -111,6 +117,10 @@ class Server {
     }
   }
 
+  async renderDisabled(req, res) {
+    res.status(500).send("preview rendering disabled");
+  }
+
   async renderPreview(req, res) {
     try {
       const path = req.params[0]