2023-dev-notes

intercept-proxy-mitmweb.md

2023.02.03

Intercept proxy mitmweb

mitmweb: proxy server that able to intercept(pause/modify) http requests/responses for web/android/ios development

1. Install mitmweb and start it by mitmweb -p 3033
2. Setup proxy on android emulator setting -> proxy and set hostname to your local ip by $ ipconfig and 3033 port
3. Open browser navigate to mitmweb localhost:8081 and on pause filter type ~u apikeyword

portable-python-in-electron.md

portable-python-in-electron.md

2023.05.19 electron packed portable python v3 and git example

ExpressLRS Configurator 1.5.9 https://github.com/ExpressLRS/ExpressLRS-Configurator/releases/tag/v1.5.9

on macOS, it installed portable python and git with electron installer to

~/Applications/ExpressLRS Configurator.app/Contents/dependencies/darwin_amd64/python-portable-darwin-3.8.4/

and

~/Applications/ExpressLRS Configurator.app/Contents/dependencies/darwin_amd64/git-2.29.2/

related code

const portableGitLocation = path.join(
      dependenciesPath,
      'darwin_amd64/git-2.29.2/bin'
    );
    PATH = prependPATH(PATH, portablePythonLocation);
    PATH = prependPATH(PATH, portableGitLocation);
    localApiServerEnv.GIT_EXEC_PATH = path.join(
      dependenciesPath,
      'darwin_amd64/git-2.29.2/libexec/git-core'
    );
  }

https://github.com/ExpressLRS/ExpressLRS-Configurator/blob/85d9b51eda73619b9feb0a38b4fcf2af69e9507a/src/main.dev.ts#L312-L322

      "extraFiles": [
        "dependencies/darwin_amd64",
        "dependencies/get-platformio.py"
      ]

https://github.com/ExpressLRS/ExpressLRS-Configurator/blob/85d9b51eda73619b9feb0a38b4fcf2af69e9507a/package.json#L65-L67

found by fd

same-site-respoinse-header.md

2023.01.04

Same site response header

Refers to this article, as of Feb, 2020, setting 'samesite=none' in Set-Cookie http response header is necessary for Chrome browser.

I'm working on a react frontend app to a php server powered by symphony right now and the cookie and the cross-site http request is not working.

After testing:

It would work if response header set-cookie is set-cookie: connect.sid=s%3A0dEY7p75z15C_S4zafGq3aEnii6EayEg.nwM4BV%2BKGo8e9y9cMEtfFQZfnAZH51LiliJaPsaAJio; Path=/; HttpOnly; Secure; SameSite=None (tested on express.js)

It WON'T work if response header set-cookie is Set-Cookie: PHPSESSID=t4ejuk7sse0lir5v7juasj28b0; path=/; HttpOnly. (tested on symphony)

Secure; SameSite=None in set-cookie is a must for cross-site http request now.

Reproduce Steps

1. Run a server with a domain that https enabled(nginx+cloudflare in my case)

server.js(node.js)

//@ts-nocheck

import express from 'express';
import session from 'express-session';
import cors from 'cors';

const app = express();

app.set('trust proxy', 1);
app.use(
  session({
    secret: 'keyboard cat',
    cookie: {
      secure: true,
      sameSite: 'none',
    },
  }),
);

app.use(cors({ credentials: true, origin: true }));

app.get('/', (req, res) => {
  if (req.session.test === 1) {
    return res.send('you got session id already it ');
  }
  req.session.test = 1;
  return res.send('just got session');
});

app.listen(3001, () => {
  console.log('listening to 3001');
});

client.js(chrome browser)

fetch('https://yourdomain.com/', {
  method: 'GET',
  redirect: 'follow',
  credentials: 'include',
})
  .then((response) => response.text())
  .then((result) => console.log(result))
  .catch((error) => console.log('error', error));

You should see just got session at the first request on client then see 'you got session id already it ' on second request since the cookie is attached cross-domain successfully

sqlcipher-open-db-file.md

sqlcipher-open-db-file.md

db file path: ~/Desktop/mydb

make sure sqlcipher is installed, my version is SQLite version 3.42.0 2023-05-16 12:36:15 (SQLCipher 4.5.5 community)

1. open the db file sqlcipher ~/Desktop/mydb
2. PRAGMA key = 'your_password';
3. it should reply ok
4. try .tables to see tables or .schema to see schema

throttle-in-dart.md

The Generics type Function(T a) is only allowed one paramter now. Not sure how to improve the type yet.

Usage

$ dart ./main.dart

0
2
4
6
8

main.dart

import 'dart:async';
import './throttle.dart';


void main() async {
  var f = Throttle.create((int n) {
    print(n);
  }, duration: const Duration(milliseconds: 1000));

  for (int i = 0; i < 10; i++) {
    f(i);
    await Future.delayed(Duration(milliseconds: 500));
  }
}

throttle.dart

import 'dart:async';

typedef ThrottledFunction<T> = Function(T a);

class Throttle<T> {
  Duration duration;
  Timer? _timer;
  ThrottledFunction<T>? _throttledFunction;

  Throttle(this._throttledFunction,
      {this.duration = const Duration(milliseconds: 500)});

  void call(T a) {
    if (_timer == null || !_timer!.isActive) {
      _timer = Timer(duration, () {
        _throttledFunction!(a);
        _timer = null;
      });
    }
  }

  static Throttle<T> create<T>(ThrottledFunction<T> function,
      {duration = const Duration(milliseconds: 500)}) {
    return Throttle(function, duration: duration);
  }
}