Update server/status.js

Add blockchain height to Fulcrum status

server/status.js

@@ -4,70 +4,62 @@ const net = require('net');
 const port = 8080;
 const fulcrumTimeoutMs = 3000;
 
-function checkFulcrum(fulcrumUrl) {
+function queryFulcrum(fulcrumUrl, method, params = []) {
 return new Promise((resolve) => {
 if (!fulcrumUrl) {
 resolve({
-        configured: false,
+ok: false,
-        connected: false,
+result: null,
-        url: null,
 });
 return;
 }
 
+```
 let parsed;
 
 try {
   parsed = new URL(fulcrumUrl);
 } catch {
   resolve({
-        configured: true,
+    ok: false,
-        connected: false,
+    result: null,
-        url: fulcrumUrl,
   });
   return;
 }
 
 if (parsed.protocol !== 'tcp:') {
   resolve({
-        configured: true,
+    ok: false,
-        connected: false,
+    result: null,
-        url: fulcrumUrl,
   });
   return;
 }
 
 const host = parsed.hostname;
-    const port = Number(parsed.port);
+const fulcrumPort = Number(parsed.port);
 
-    if (!host || !port) {
+if (!host || !fulcrumPort) {
   resolve({
-        configured: true,
+    ok: false,
-        connected: false,
+    result: null,
-        url: fulcrumUrl,
   });
   return;
 }
 
 const socket = net.createConnection({
   host,
-      port,
+  port: fulcrumPort,
 });
 
 let response = '';
 let settled = false;
 
-    const finish = (connected) => {
+const finish = (value) => {
   if (settled) return;
   settled = true;
 
   socket.destroy();
-
+  resolve(value);
-      resolve({
-        configured: true,
-        connected,
-        url: fulcrumUrl,
-      });
 };
 
 socket.setTimeout(fulcrumTimeoutMs);
@@ -77,8 +69,8 @@ function checkFulcrum(fulcrumUrl) {
     `${JSON.stringify({
       jsonrpc: '2.0',
       id: 1,
-          method: 'server.version',
+      method,
-          params: ['Munin Bitcoin', '1.4'],
+      params,
     })}\n`,
   );
 });
@@ -86,22 +78,100 @@ function checkFulcrum(fulcrumUrl) {
 socket.on('data', (data) => {
   response += data.toString();
 
-      if (response.includes('"result"')) {
+  const lines = response.split('\n');
-        finish(true);
+
-      } else if (response.includes('"error"')) {
+  for (const line of lines) {
-        finish(false);
+    if (!line.trim()) continue;
+
+    let message;
+
+    try {
+      message = JSON.parse(line);
+    } catch {
+      continue;
+    }
+
+    if (message.error) {
+      finish({
+        ok: false,
+        result: null,
+      });
+      return;
+    }
+
+    if (Object.prototype.hasOwnProperty.call(message, 'result')) {
+      finish({
+        ok: true,
+        result: message.result,
+      });
+      return;
+    }
   }
 });
 
-    socket.on('timeout', () => finish(false));
+socket.on('timeout', () => {
-    socket.on('error', () => finish(false));
+  finish({
-    socket.on('close', () => finish(false));
+    ok: false,
+    result: null,
   });
+});
+
+socket.on('error', () => {
+  finish({
+    ok: false,
+    result: null,
+  });
+});
+
+socket.on('close', () => {
+  finish({
+    ok: false,
+    result: null,
+  });
+});
+```
+
+});
+}
+
+async function getFulcrumStatus(fulcrumUrl) {
+const version = await queryFulcrum(
+fulcrumUrl,
+'server.version',
+['Munin Bitcoin', '1.4'],
+);
+
+if (!version.ok) {
+return {
+configured: Boolean(fulcrumUrl),
+connected: false,
+url: fulcrumUrl,
+serverVersion: null,
+blockchainHeight: null,
+};
+}
+
+const headers = await queryFulcrum(
+fulcrumUrl,
+'blockchain.headers.subscribe',
+[],
+);
+
+return {
+configured: Boolean(fulcrumUrl),
+connected: true,
+url: fulcrumUrl,
+serverVersion: version.result,
+blockchainHeight:
+headers.ok && headers.result
+? headers.result.height ?? null
+: null,
+};
 }
 
 async function getStatus() {
 const fulcrumUrl = process.env.MUNIN_FULCRUM_URL || null;
-  const fulcrum = await checkFulcrum(fulcrumUrl);
+const fulcrum = await getFulcrumStatus(fulcrumUrl);
 
 return {
 service: 'running',
@@ -118,6 +188,7 @@ const server = http.createServer(async (req, res) => {
 try {
 const status = await getStatus();
 
+```
   res.writeHead(200, {
     'Content-Type': 'application/json',
   });
@@ -139,6 +210,8 @@ const server = http.createServer(async (req, res) => {
 }
 
 return;
+```
+
 }
 
 res.writeHead(404);