# Colorize log output using Chalk

**URL:** <https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497>\
**Category:** General\
**Created:** [14 December 2020 17:03 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497 "2020-12-14T17:03:02Z")\
**Posts on this page:** 15\
**Page:** 1

<div class="post-metadata">

**Author:** ![jayheavner](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/jayheavner/32/9804_2.png) [@jayheavner](https://discourse.nodered.org/u/jayheavner)\
**Post date:** [14 December 2020 17:03 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/1 "2020-12-14T17:03:02Z")

</div>

I've added chalk  
`npm install chalk`

I've added it to functionGlobalContext

```auto
  functionGlobalContext: {
    chalk: require('chalk')
  },

```

I've restarted node-red.

I've added it to a function

```auto
var chalk = global.get('chalk');
console.log(chalk.blue('Hello world!'));

```

It's not working. The entry is logged with default color.

Specifying a color like so does change the foreground color of the log entry.

```auto
console.log('\x1b[36m%s\x1b[0m', 'cyan text');

```

I've confirmed that other packages added to functionGlobalContext work and `msg.payload = chalk.toString();` results in `payload: [object Function]`.

Am I missing something or is this just not a thing that's going to work?

---

<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [14 December 2020 17:28 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/2 "2020-12-14T17:28:27Z")

</div>

what does debug show if you do this...

function --\> debug node

```auto
var chalk = global.get('chalk');
msg.payload = chalk.blue('Hello world!');
return msg;

```

---

<div class="post-metadata">

**Author:** ![jayheavner](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/jayheavner/32/9804_2.png) [@jayheavner](https://discourse.nodered.org/u/jayheavner)\
**Post date:** [14 December 2020 17:33 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/3 "2020-12-14T17:33:13Z")

</div>

> [@Steve-Mcl](#):
>
> ```auto
> var chalk = global.get('chalk');
> msg.payload = chalk.blue('Hello world!');
> return msg;
> 
> ```

If the debug node writes to debug window it displays \>

```auto
{"_msgid":"4f58986.a69dd68","payload":"Hello world!"}

```

If the debug node writes to system console it displays \>

```auto
0|node-red | 14 Dec 12:30:22 - [info] [debug:Write Log] Hello world!

```

Neither case shows colorized output.

---

<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [14 December 2020 17:37 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/4 "2020-12-14T17:37:20Z")

</div>

Quite Strange. I would have expected to see the colour escape chars. It's like chalk isn't applying them.

What happens if you fire up a node cli from the node\_module directory and try the same thing in command line ?

Have you tried others like `color`?

---

<div class="post-metadata">

**Author:** ![jayheavner](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/jayheavner/32/9804_2.png) [@jayheavner](https://discourse.nodered.org/u/jayheavner)\
**Post date:** [14 December 2020 17:55 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/5 "2020-12-14T17:55:38Z")

</div>

I don't exactly know how to run a node command from the CLI but I created a test project on the same box using npm init and added two lines to a file.

```auto
const chalk = require('chalk');
console.log(chalk.blue('Hello world!'));

```

Installed chalk `npm i chalk`

ran it `node init.js`

and it spit out `Hello world!` in blue.

I did try colors. It also didn't work and threw error (`"TypeError: Cannot read property 'red' of undefined"`) if I tried chaining `console.log('i like cake and pies'.underline.red);`

---

<div class="post-metadata">

**Author:** ![jayheavner](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/jayheavner/32/9804_2.png) [@jayheavner](https://discourse.nodered.org/u/jayheavner)\
**Post date:** [14 December 2020 18:19 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/6 "2020-12-14T18:19:19Z")

</div>

For now, I've dumped all the color codes I want to a global and then built a subflow that colorizes output using passed params or set environment vars on the subflow. It's not great but it seems to be ok until I can resolve it.

```auto
[{"id":"e98b18f5.0a2b08","type":"subflow","name":"Colorized Output","info":"","category":"","in":[{"x":40,"y":40,"wires":[{"id":"ea5fb272.a74cb"}]}],"out":[{"x":400,"y":40,"wires":[{"id":"564fbdb9.ab76e4","port":0}]}],"env":[{"name":"color","type":"str","value":"Green"},{"name":"bgColor","type":"str","value":""},{"name":"bright","type":"bool","value":"true"},{"name":"output","type":"str","value":"Hello World"}],"color":"#DDAA99"},{"id":"564fbdb9.ab76e4","type":"function","z":"e98b18f5.0a2b08","name":"Colorize output","func":"let colors = global.get('logColors');\nlet bright = msg.bright ? colors.Bright : '';\nlet color = msg.color !== '' ? colors.fg[msg.color] : '';\nlet bgColor = msg.bgColor !== '' ? colors.bg[msg.bgColor] : '';\n\nconsole.log(bright, color, bgColor, msg.output, colors.Reset);\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","x":280,"y":40,"wires":[[]]},{"id":"ea5fb272.a74cb","type":"function","z":"e98b18f5.0a2b08","name":"Vars","func":"msg.color = msg.color || env.get(\"color\");\nmsg.bgColor = msg.bgColor || env.get(\"bgColor\");\nmsg.bright = msg.bright || env.get(\"bright\");\nmsg.ouput === msg.output || env.get(\"output\");\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","x":130,"y":40,"wires":[["564fbdb9.ab76e4"]]},{"id":"a22b39ce.1863b8","type":"template","z":"98803193.f8aa","name":"","field":"output","fieldType":"msg","format":"handlebars","syntax":"mustache","template":"{{room}} turned off.","output":"str","x":420,"y":1060,"wires":[["7a5b894.db93578"]]},{"id":"7a5b894.db93578","type":"subflow:e98b18f5.0a2b08","z":"98803193.f8aa","name":"Colorized Log Output","env":[],"x":600,"y":1060,"wires":[["325436e6.c5bd8a"]]},{"id":"769f8836.726e58","type":"inject","z":"98803193.f8aa","name":"Timestamp","props":[{"p":"payload"},{"p":"room","v":"Living Room","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":260,"y":1060,"wires":[["a22b39ce.1863b8"]]},{"id":"325436e6.c5bd8a","type":"debug","z":"98803193.f8aa","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","statusVal":"","statusType":"auto","x":790,"y":1060,"wires":[]},{"id":"bf0a73b8.1ca97","type":"template","z":"98803193.f8aa","name":"","field":"output","fieldType":"msg","format":"handlebars","syntax":"mustache","template":"{{room}} turned off.","output":"str","x":420,"y":1120,"wires":[["23b6d894.4192f8"]]},{"id":"23b6d894.4192f8","type":"subflow:e98b18f5.0a2b08","z":"98803193.f8aa","name":"Colorized Log Output","env":[],"x":600,"y":1120,"wires":[["c6252302.3f6ab"]]},{"id":"64911ff0.f763e","type":"inject","z":"98803193.f8aa","name":"Timestamp","props":[{"p":"payload"},{"p":"room","v":"Living Room","vt":"str"},{"p":"color","v":"Blue","vt":"str"},{"p":"bgColor","v":"Red","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":260,"y":1120,"wires":[["bf0a73b8.1ca97"]]},{"id":"c6252302.3f6ab","type":"debug","z":"98803193.f8aa","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","statusVal":"","statusType":"auto","x":790,"y":1120,"wires":[]}]

```

---

<div class="post-metadata">

**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [14 December 2020 21:54 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/7 "2020-12-14T21:54:14Z")

</div>

I think that the debug tab filters out the codes. They wouldn't work anyway of course since the debug tab uses HTML and not terminal colour codes.

Perhaps chalk is taking its environment into account and thinks that your terminal doesn't have colour support? How are you running Node-RED? I know that when I run it from systemd, I don't get all of the usual environment variables that you would expect from a full BASH shell and that includes the XTERM variable that you might need. Maybe try adding the appropriate variables to the systemd startup script.

---

<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [14 December 2020 22:23 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/8 "2020-12-14T22:23:14Z")

</div>

> [@TotallyInformation](#):
>
> Perhaps chalk is taking its environment into account and thinks that your terminal

I think it tries to be clever & not add the escape codes if it doesn't detect a capable console & as the node-red function node is sandboxed, i believe thats why it doesnt work.

Would be nice if there was an override flag to ignore console & output the strings regardless. there may be something in there but i dont know. would need to dig through code or ask on repo.

---

<div class="post-metadata">

**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [14 December 2020 22:24 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/9 "2020-12-14T22:24:35Z")

</div>

If the environment vars are set before starting Node-RED it might work? Maybe start it manually to see if it does.

---

<div class="post-metadata">

**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [14 December 2020 22:42 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/10 "2020-12-14T22:42:12Z")

</div>

I think if you set ` debugUseColors: true,` in settings.js then you can just use ansi colour codes

```auto
[{"id":"546a404a.1d369","type":"inject","z":"ab9333b5.f44f6","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"\\033[31;1;4mHello\\033[0m","payloadType":"str","x":120,"y":2200,"wires":[["7043a930.ca3328"]]},{"id":"7043a930.ca3328","type":"function","z":"ab9333b5.f44f6","name":"","func":"console.log(\"\\033[31;1;4mHello\\033[0m\")\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","x":300,"y":2200,"wires":[[]]}]

```

---

<div class="post-metadata">

**Author:** ![jayheavner](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/jayheavner/32/9804_2.png) [@jayheavner](https://discourse.nodered.org/u/jayheavner)\
**Post date:** [14 December 2020 23:27 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/11 "2020-12-14T23:27:20Z")

</div>

Thanks all, I will take a look at all of this later and report back.

---

<div class="post-metadata">

**Author:** ![jayheavner](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/jayheavner/32/9804_2.png) [@jayheavner](https://discourse.nodered.org/u/jayheavner)\
**Post date:** [15 December 2020 16:29 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/12 "2020-12-15T16:29:01Z")

</div>

You're 100% right. It's detecting the console and setting a level of 0 (no color). Chalk is using another package [https://github.com/chalk/supports-color](https://github.com/chalk/supports-color) to determine support. It looks like some environments are hard-coded. Otherwise it's CLI flags and environment variables.

One fix is to add the environment variable to settings.js.

```auto
process.env.FORCE_COLOR = "1";

```

However, it's also possible to instantiate the Chalk object with some startup parameters to force a color support level. I completely missed this in the README cuz I was skimming and searching the wrong phrases. It wasn't until I looked at the code and saw they were using `level` that I searched that term in the README.

```auto
var chalk = global.get('chalk');
chalk.level = 2  
console.log(chalk.green('Hello world!'));
return msg;

```

TL;DR RTFM

---

<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [15 December 2020 16:39 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/13 "2020-12-15T16:39:38Z")

</div>

I too only skimmed the readme - wasn't obvious

Working for me using the method described in the readme

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/8/c/8c8559658c1142a79e59759829008105791f2fae.png)

```auto
var chalk = global.get('chalk');
const ctx = new chalk.Instance({level: 2});
msg.payload = ctx.blue.bgRed.bold('Hello world!')
console.log(msg.payload );
return msg;

```

---

<div class="post-metadata">

**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [15 December 2020 21:04 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/14 "2020-12-15T21:04:20Z")

</div>

I'd guessed that was the problem since I've hit similar issues in the past with consoles.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [13 February 2021 21:04 UTC](https://discourse.nodered.org/t/colorize-log-output-using-chalk/37497/15 "2021-02-13T21:04:27Z")

</div>

Closed on 13 February 2021 21:04 UTC

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