close chidl processes when parent exits

packages/api/src/controllers/connections.js

@@ -27,7 +27,12 @@ module.exports = {
   },
   test(req, res) {
     const subprocess = fork(process.argv[1], ['connectProcess']);
-    subprocess.on('message', (resp) => res.json(resp));
+    subprocess.on('message', (resp) => {
+      const { msgtype } = res;
+      if (msgtype == 'connected' || msgtype == 'error') {
+        res.json(resp);
+      }
+    });
     subprocess.send(req.body);
   },
 

packages/api/src/controllers/databaseConnections.js

@@ -24,6 +24,7 @@ module.exports = {
     resolve(response);
     delete this.requests[msgid];
   },
+  handle_ping() {},
 
   async ensureOpened(conid, database) {
     const existing = this.opened.find((x) => x.conid == conid && x.database == database);

packages/api/src/controllers/serverConnections.js

@@ -14,6 +14,8 @@ module.exports = {
   handle_error(conid, { error }) {
     console.log(`Error in server connection ${conid}: ${error}`);
   },
+  handle_ping() {
+  },
 
   async ensureOpened(conid) {
     const existing = this.opened.find(x => x.conid == conid);

packages/api/src/controllers/sessions.js

@@ -58,6 +58,8 @@ module.exports = {
     jsldata.notifyChangedStats(stats);
   },
 
+  handle_ping() {},
+
   create_meta: 'post',
   async create({ conid, database }) {
     const sesid = uuidv1();

packages/api/src/proc/connectProcess.js

@@ -1,13 +1,15 @@
 const engines = require('@dbgate/engines');
 const driverConnect = require('../utility/driverConnect');
+const childProcessChecker = require('../utility/childProcessChecker');
 
 function start() {
-  process.on('message', async connection => {
+  childProcessChecker();
+  process.on('message', async (connection) => {
     try {
       const driver = engines(connection);
       const conn = await driverConnect(driver, connection);
       const res = await driver.getVersion(conn);
-      process.send(res);
+      process.send({ msgtype: 'connected', ...res });
     } catch (e) {
       console.log(e);
       process.send({ msgtype: 'error', error: e.message });

packages/api/src/proc/databaseConnectionProcess.js

@@ -1,5 +1,6 @@
 const engines = require('@dbgate/engines');
 const driverConnect = require('../utility/driverConnect');
+const childProcessChecker = require('../utility/childProcessChecker');
 
 let systemConnection;
 let storedConnection;
@@ -67,6 +68,7 @@ async function handleMessage({ msgtype, ...other }) {
 }
 
 function start() {
+  childProcessChecker();
   process.on('message', async (message) => {
     try {
       await handleMessage(message);

packages/api/src/proc/serverConnectionProcess.js

@@ -1,5 +1,6 @@
 const engines = require('@dbgate/engines');
 const driverConnect = require('../utility/driverConnect');
+const childProcessChecker = require('../utility/childProcessChecker');
 
 let systemConnection;
 let storedConnection;
@@ -29,7 +30,8 @@ async function handleMessage({ msgtype, ...other }) {
 }
 
 function start() {
-  process.on('message', async message => {
+  childProcessChecker();
+  process.on('message', async (message) => {
     try {
       await handleMessage(message);
     } catch (e) {

packages/api/src/proc/sessionProcess.js

@@ -3,6 +3,7 @@ const uuidv1 = require('uuid/v1');
 const path = require('path');
 const fs = require('fs');
 const _ = require('lodash');
+const childProcessChecker = require('../utility/childProcessChecker');
 
 const driverConnect = require('../utility/driverConnect');
 const { jsldir } = require('../utility/directories');
@@ -132,6 +133,7 @@ async function handleMessage({ msgtype, ...other }) {
 }
 
 function start() {
+  childProcessChecker();
   process.on('message', async (message) => {
     try {
       await handleMessage(message);

packages/api/src/utility/childProcessChecker.js

@@ -0,0 +1,17 @@
+let counter = 0;
+ 
+function childProcessChecker() {
+  setInterval(() => {
+    try {
+      process.send({ msgtype: 'ping', counter: counter++ });
+    } catch (ex) {
+      // This will come once parent dies.
+      // One way can be to check for error code ERR_IPC_CHANNEL_CLOSED
+      //     and call process.exit()
+      console.log('parent died', ex.toString());
+      process.exit();
+    }
+  }, 1000);
+}
+
+module.exports = childProcessChecker;