From 32cbe9df505bf73b1692f53eff1e5124dff740ff Mon Sep 17 00:00:00 2001
From: Robsdedude <rouven.bauer@neo4j.com>
Date: Mon, 18 Aug 2025 15:29:41 +0200
Subject: [PATCH] TestKit backend: truncate logging to avoid clogging ram

Writing to stdout in nodejs is done asynchronously. So when adding data to the
queue faster than it can be flushed, the process will eventually crash because
the system is running out of memory. By limiting the length of log messages,
this problem can be avoided.
---
 packages/testkit-backend/deno/index.ts          | 17 +++++++++++++++--
 .../src/channel/testkit-protocol.js             |  4 +++-
 .../testkit-backend/src/console.configurable.js |  8 ++++++--
 packages/testkit-backend/src/index.js           | 13 ++++++++++++-
 4 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/packages/testkit-backend/deno/index.ts b/packages/testkit-backend/deno/index.ts
index a0a248d58..e89825d8d 100644
--- a/packages/testkit-backend/deno/index.ts
+++ b/packages/testkit-backend/deno/index.ts
@@ -10,6 +10,7 @@ import {
 import channel from "./channel.ts";
 import controller from "./controller.ts";
 import { RequestHandlerMap } from "./domain.ts";
+import util from "node:util";
 
 const requestHandlers: RequestHandlerMap = handlers as RequestHandlerMap;
 
@@ -26,11 +27,23 @@ const binder = new CypherNativeBinders(neo4j);
 const descriptor = ["async", "deno"];
 const shouldRunTest = getShouldRunTest(descriptor);
 const getFeatures = createGetFeatures(descriptor);
-const logLevel = Deno.env.get("TEST_LOG_LEVEL");
+const logLevel = Deno.env.get("TEST_LOG_LEVEL") ?? "info";
 const createContext = () =>
   new Context(shouldRunTest, getFeatures, binder, logLevel);
 
-configurableConsole.install(logLevel);
+const logWrapper = (...args) => {
+  let output = args.map((arg) => {
+    if (typeof arg === "string") return arg;
+    return util.inspect(arg, { colors: Deno.stdout.isTTY });
+  }).join(" ") + "\n";
+  if (output.length > 1000 * 2 + 3) {
+    output = output.substring(0, 1000) + "..." +
+      output.substring(output.length - 1000);
+  }
+  Deno.stdout.write(new TextEncoder().encode(output));
+};
+
+configurableConsole.install(logLevel, logWrapper);
 const listener = channel.listen(9876);
 const handle = controller.createHandler(neo4j, createContext, requestHandlers);
 
diff --git a/packages/testkit-backend/src/channel/testkit-protocol.js b/packages/testkit-backend/src/channel/testkit-protocol.js
index f23c38aa2..21777e23f 100644
--- a/packages/testkit-backend/src/channel/testkit-protocol.js
+++ b/packages/testkit-backend/src/channel/testkit-protocol.js
@@ -61,8 +61,10 @@ export default class Protocol extends EventEmitter {
   }
 
   serializeResponse (response) {
+    const { name, data } = response
     const responseStr = stringify(response)
-    console.log('> writing response', responseStr)
+    console.log('> writing response' + name)
+    console.debug(data)
     return ['#response begin', responseStr, '#response end'].join('\n') + '\n'
   }
 
diff --git a/packages/testkit-backend/src/console.configurable.js b/packages/testkit-backend/src/console.configurable.js
index 3c32e9e9c..b459a3abe 100644
--- a/packages/testkit-backend/src/console.configurable.js
+++ b/packages/testkit-backend/src/console.configurable.js
@@ -20,13 +20,17 @@ const config = {
 }
 
 export default {
-  install (level = 'info') {
+  install (level = 'info', logWrapper) {
     this.setLevel(level)
     // eslint-disable-next-line no-global-assign
     console = new Proxy({}, {
       get: (_, method) => (...args) => {
         if (config.canRun(method)) {
-          originalConsole[method].apply(originalConsole, args)
+          if (logWrapper != null) {
+            logWrapper(...args)
+          } else {
+            originalConsole[method].apply(originalConsole, args)
+          }
         }
       }
     })
diff --git a/packages/testkit-backend/src/index.js b/packages/testkit-backend/src/index.js
index 6a3466fec..58f679300 100644
--- a/packages/testkit-backend/src/index.js
+++ b/packages/testkit-backend/src/index.js
@@ -9,6 +9,7 @@ import * as REQUEST_HANDLERS from './request-handlers.js'
 import * as RX_REQUEST_HANDLERS from './request-handlers-rx.js'
 import remoteConsole from './console.remote.js'
 import configurableConsole from './console.configurable.js'
+import util from 'util'
 
 const SUPPORTED_TLS = (() => {
   if (tls.DEFAULT_MAX_VERSION) {
@@ -40,7 +41,17 @@ function main () {
   const shouldRunTest = getShouldRunTest([...driverDescriptorList, sessionTypeDescriptor])
   const getFeatures = createGetFeatures([sessionTypeDescriptor], SUPPORTED_TLS)
 
-  configurableConsole.install(process.env.TEST_LOG_LEVEL || 'info')
+  const logWrapper = (...args) => {
+    let output = args.map(arg => {
+      if (typeof arg === 'string') return arg
+      return util.inspect(arg, { colors: process.stdout.isTTY })
+    }).join(' ') + '\n'
+    if (output.length > 1000 * 2 + 3) {
+      output = output.substring(0, 1000) + '...' + output.substring(output.length - 1000)
+    }
+    process.stdout.write(output)
+  }
+  configurableConsole.install(process.env.TEST_LOG_LEVEL || 'info', logWrapper)
 
   const newChannel = () => {
     if (channelType.toUpperCase() === 'WEBSOCKET') {