new toy

split-proxy/index.js

@@ -0,0 +1,101 @@
+const express = require('express');
+const config = require('./config');
+const logger = require('./logger');
+const RPCProxy = require('./proxy');
+
+const app = express();
+const proxy = new RPCProxy();
+
+// Middleware to parse JSON bodies
+app.use(express.json({
+  limit: '50mb',
+  type: 'application/json'
+}));
+
+// Health check endpoint
+app.get('/health', (req, res) => {
+  res.json({
+    status: 'ok',
+    primaryEndpoint: config.primaryRpc,
+    secondaryEndpoint: config.secondaryRpc,
+    primaryRole: config.primaryRole,
+    currentStreamEndpoint: proxy.streamEndpoint,
+    currentCompareEndpoint: proxy.compareEndpoint,
+  });
+});
+
+// Main JSON-RPC endpoint
+app.post('/', async (req, res) => {
+  await proxy.handleRequest(req, res);
+});
+
+// Error handling middleware
+app.use((err, req, res, next) => {
+  logger.error({
+    error: err.message,
+    stack: err.stack,
+  }, 'Unhandled error');
+
+  if (!res.headersSent) {
+    res.status(500).json({
+      jsonrpc: '2.0',
+      error: {
+        code: -32603,
+        message: 'Internal error',
+      },
+      id: req.body?.id,
+    });
+  }
+});
+
+// Start server
+const server = app.listen(config.port, () => {
+  logger.info({
+    port: config.port,
+    primaryRpc: config.primaryRpc,
+    secondaryRpc: config.secondaryRpc,
+    primaryRole: config.primaryRole,
+    latencyThreshold: config.latencyThresholdMs,
+    sizeDiffThreshold: config.sizeDiffThreshold,
+  }, 'ETH JSON-RPC proxy started');
+});
+
+// Graceful shutdown
+process.on('SIGTERM', () => {
+  logger.info('SIGTERM received, shutting down gracefully');
+  server.close(() => {
+    logger.info('Server closed');
+    process.exit(0);
+  });
+});
+
+process.on('SIGINT', () => {
+  logger.info('SIGINT received, shutting down gracefully');
+  server.close(() => {
+    logger.info('Server closed');
+    process.exit(0);
+  });
+});
+
+// Dynamic role switching with SIGUSR1
+process.on('SIGUSR1', () => {
+  logger.info('SIGUSR1 received, switching primary/secondary roles');
+  try {
+    const newConfig = proxy.switchRoles();
+    logger.info({
+      ...newConfig,
+      signal: 'SIGUSR1',
+    }, 'Successfully switched roles');
+  } catch (error) {
+    logger.error({
+      error: error.message,
+      signal: 'SIGUSR1',
+    }, 'Failed to switch roles');
+  }
+});
+
+// Log instructions for role switching on startup
+logger.info('To switch primary/secondary roles at runtime, send SIGUSR1 signal:');
+logger.info('  kill -USR1 <pid>  OR  docker kill -s USR1 <container>');
+
+module.exports = app;