Recently I deleted yarn.lock file manually on the monorepo and there are tons of dependencies compatibility issue.

And I found yarn upgrade and yarn outdated are useful commands.

Turned out yarn install or just yarn would only update yarn.lock whenever dependencies in package.json changed. It won't update all packages to the latest stable version ( a.b.c, fixed a, and latest b and c ).

We can and should manually upgrade by yarn upgrade or npm upgrade.

This command updates dependencies to their latest version based on the version range specified in the package.json file. The yarn.lock file will be recreated as well.

Timing for me to use some yarn commands

yarn install or yarn -> on local dev

yarn install --frozen-lockfile --prefer-offline -> on ci

yarn outdated or yarn upgrade -> when we have time and wanna improve code quality by updating dependencies to latest stable version

https://classic.yarnpkg.com/lang/en/docs/cli/upgrade/

https://docs.npmjs.com/updating-packages-downloaded-from-the-registry

Sometimes I need a quick https setup for development environment.

Caddy used to be my go-to but I expereienced ssl3 error on v2.x a few times and found no way to solve it.

I have just tried this docker-nginx-auto-ssl in docker-compose.yml and it worked in 1 min.

docker-compose.yml

# docker-compose.yml
version: '2'
services:
  nginx:
    image: valian/docker-nginx-auto-ssl
    restart: on-failure
    volumes:
      - ssl_data:/etc/resty-auto-ssl
    environment:
      ALLOWED_DOMAINS: 'example.com'
      SITES: 'example.com=localhost:3001'
    network_mode: 'host'

volumes:
  ssl_data:
~

Pattern properties in json schema is useful when validating random amount of objects key.

for example, a users object contains 0 to n users data key by user id.

data

{
   "userid1":{...},
   "userid100":{...}
}

test.js

const fjs = require('fluent-json-schema');
const Ajv = require('ajv');

const schema = fjs
  .object()
  .additionalProperties(false)
  //   .prop('prop')
  .patternProperties({ '^fo.*$': fjs.string() });

console.log('schema.valueOf()', schema.valueOf());
const ajv = new Ajv({ allErrors: true });
const validate = ajv.compile(schema.valueOf());

const data = {
  foo: 'pass',
};

let valid = validate(data);
console.log({ valid });
console.log('validate.errors', validate.errors);

const data2 = {
  test: 'test',
};

let valid2 = validate(data2);
console.log({ valid2 });
console.log('validate.errors', validate.errors);

node v16.14.0

"ajv": "^8.11.0"

"fluent-json-schema": "^3.1.0"

references:

https://stackoverflow.com/a/30809082/6414615

https://github.com/fastify/fluent-json-schema/blob/master/src/ObjectSchema.test.js#L421-L435

requirement: print 1 page only and hlaf of the page should be the same content

The jsfiddle that fits my needs. /39 below

HTML

<div class="box1">
  box1
</div>

<div class="box2">
  box2
</div>

css

  @page {
    margin: 0;
    size: A4;
  }

  body {
    -webkit-print-color-adjust: exact;
  }
  

  html,
  body {
    margin: 0;
    height: 297mm;
    width: 210mm;
    position: relative;
  }


  .box1 {
    margin-top:10mm;
    box-sizing: border-box;
    margin-left: 5mm;
    border-bottom: 1px solid red;
    position: absolute;
    top: 0;
    /* background-color: grey; */
    width: 200mm;
  }

  .box2 {
    margin-top:16mm;
    box-sizing: border-box;
    margin-left: 5mm;
    border-bottom: 1px solid blue;
    position: absolute;
    top: 50%;
    /* background-color: grey; */
    width: 200mm;
  }

2022.06.20

print test 4

https://jsfiddle.net/jasonHsieh/tsnv714e/39/ -> works ! manually add 6 mm margin top on box 2

https://jsfiddle.net/jasonHsieh/tsnv714e/39/ -> works ! manually add 6 mm margin top on box 2


print test 3

https://jsfiddle.net/jasonHsieh/tsnv714e/32/ -> works and default 1 page but box2 margin top has missing 6mm shorter after printing

print test 2

https://jsfiddle.net/jasonHsieh/tsnv714e/20/ -> works but default 2 pages

https://jsfiddle.net/jasonHsieh/tsnv714e/20/ -> works but default 2 pages



https://jsfiddle.net/jasonHsieh/tsnv714e/25/ -> wrong middle height size

based on:

jsfiddle http://jsfiddle.net/mturjak/2wk6Q/1949/

backup jsfiddle http://jsfiddle.net/jasonHsieh/op6uwscg/

from:

https://stackoverflow.com/a/16650459/6414615

There are 2 methods I found on the internet to inspect the memory usage on a node.js process.

1. Maximum resident set size (kbytes) by executing nodejs script ( ubuntu 18 works )
2. process.memoryUsage() in node.js API

1. /usr/bin/time -pv node --max-old-space-size=200 ./test.js
2. /usr/bin/time -pv node --max-old-space-size=4096 ./test.js

test.js

const memoryLeakAllocations = [];

const field = 'heapUsed';
const allocationStep = 10000 * 1024; // 10MB

const TIME_INTERVAL_IN_MSEC = 40;

setInterval(() => {
  const allocation = allocateMemory(allocationStep);

  memoryLeakAllocations.push(allocation);

  const mu = process.memoryUsage();
  // # bytes / KB / MB / GB
  const gbNow = mu[field] / 1024 / 1024 / 1024;
  const gbRounded = Math.round(gbNow * 100) / 100;

  console.log(`Heap allocated ${gbRounded} GB`);
}, TIME_INTERVAL_IN_MSEC);

function allocateMemory(size) {
  // Simulate allocation of bytes
  const numbers = size / 8;
  const arr = [];
  arr.length = numbers;
  for (let i = 0; i < numbers; i++) {
    arr[i] = i;
  }
  return arr;
}

references:

https://nodejs.org/en/docs/guides/backpressuring-in-streams/

https://blog.appsignal.com/2021/12/08/nodejs-memory-limits-what-you-should-know.html

/usr/local/etc/nginx.conf or /etc/nginx/nginx.conf

Below config would serve /somewhere directory files

.....
location / {
            autoindex on;
            alias /somewhere;
            # root /somewhere;
             
}
.....

htpasswd -bdc basic-auth-file admin 12345

cat basic-auth-file

location / {
            auth_basic            "Restricted Area for Private Use Only";
            auth_basic_user_file  /basic-auth-file;
            autoindex on;
            root /somewhere;
        }

add below to top of nginx.conf

daemon off;
error_log /dev/stdout info;

now run nginx would run without daemon

from: https://stackoverflow.com/a/23328458/6414615 https://docs.nginx.com/nginx/admin-guide/web-server/serving-static-content/ https://stackoverflow.com/questions/9454150/nginx-password-protected-dir-with-autoindex-feature https://www.jianshu.com/p/1c0691c9ad3c

Usually it writes to path /etc/logrotate.d/pm2-root

https://github.com/Unitech/pm2/blob/master/lib/templates/logrotate.d/pm2

%HOME_PATH%/pm2.log %HOME_PATH%/logs/*.log {
        rotate 12
        weekly
        missingok
        notifempty
        compress
        delaycompress
        copytruncate
        create 0640 %USER% %USER%
}

https://github.com/keymetrics/pm2-logrotate

pm2-logrotate is easier than editing manually in /etc/logrotate.d/pm2-root

Useful for javscript/typescript monorepo to copy previous installed node_modules.

My use case is on gitlab-runner shell executor to faster yarn install without messing with problematic gitlab-runner cache setting.

rsync -a -m --include="*/" --include="**/node_modules/**" --exclude="*" ./ ~/git/test/rsync-test

https://github.com/JaosnHsieh/my-next-ts-electron-template

https://github.com/JaosnHsieh/my-next-ts-electron-template

A HTTP POST API /log for hobby apps.

1. log rotate by /etc/logrotate.d/nginx without extra configuring
2. api limit by limit_req_zone
3. app client might add a sample rate to prevent abuse requests such as sentry javascript sdk sample rate 0 to 1

/etc/nginx/sites-enable/default.conf

.....

limit_req_zone $binary_remote_addr zone=mytracking:10m rate=10r/s;

log_format my-tracking-format escape=json '$remote_addr - $remote_user [$time_local] '
                       '"$request" $status $bytes_sent '
                       '"$http_referer" "$http_user_agent" "$request_body"';

server {
  listen 80 default_server;
  
.....

location = /log {
  limit_req zone=mytracking burst=20 nodelay;
  access_log /mnt/logs/nginx/my-tracking.access.log my-tracking-format;
  proxy_pass http://localhost:80/empty;
}

location = /empty {
  access_log off;
  return 200 'logged';
}

.....
}

server {
  listen 443 ssl;
  
  .....
  
  location = /log {
    limit_req zone=mytracking burst=20 nodelay;
    access_log /mnt/logs/nginx/my-tracking.access.log my-tracking-format;
    proxy_pass http://localhost:80/empty;
  }
  .....
}

version: nginx version: nginx/1.14.0 (Ubuntu)

request

curl -d '{"key1":"value1", "key2":"value2"}' -H "Content-Type: application/json" -X POST https://yourserver.com/log

checking log

tail -f /var/log/nginx/my-tracking.access.log

references:

https://stackoverflow.com/questions/17609472/really-logging-the-post-request-body-instead-of-with-nginx

https://stackoverflow.com/a/14034744/6414615

Built-in functions in browser and node.js v16 atob and btoa are not utf8 compatible.

And the btoa npm module is not throwing the error as browser, node.js does.

reproduce.js

const utf8Str = `style=“color:white”`;
const encodedStr = btoa(utf8Str);
const decodedStr = atob(encodedStr);
console.log(decodedStr === utf8Str);
VM111:2 Uncaught DOMException: Failed to execute 'btoa' on 'Window': The string to be encoded contains characters outside of the Latin1 range.
    at <anonymous>:2:20

Solution:

https://stackoverflow.com/a/30106551/6414615

Some userful, maybe runnable WebRTC code I found on the internet.

1. MDN signaling flow with very detailed article and code. Stopped updating though

article https://developer.mozilla.org/en-US/docs/Web/API/WebRTC_API/Signaling_and_video_calling

code https://github.com/mdn/samples-server/tree/master/s/webrtc-from-chat

2. WebRTC organization, many samples and some are experimental APIs with E2E testing, little explanations, up to date.

demo https://webrtc.github.io/samples/

code https://github.com/webrtc/samples

3. Pino ( Golang WebRTC implmentation ) with same javascript and golang runnable samples. up to date.

https://github.com/pion/example-webrtc-applications