bcherny

Notes on Martin Kleppmann's excellent Designing Data-Intensive Applications.

Chapter 1: Reliable, Scalable, and Maintainable Applications

• Data Systems
  • Dimensions to consider when thinking about data systems: access patterns, performance characteristics, implementations.
  • Modern data systems often blur the lines between databases, caches, streams, etc.
• Reliability
  • Systems should perform the expected function at a given level of performance, and be tolerant to faults and user mistakes
• Fault: One component of a system deviating from its spec. Prefer tolerating faults over preventing them (except for things like security issues). Faults stem from hardware failures, software failures, and human error (in a study, config errors caused most outages).

christophengelmayer

<div class="relative" style="padding-top: 56.25%">
  <iframe class="absolute inset-0 w-full h-full" src="https://www.youtube-nocookie.com/embed/FMrtSHAAPhM" frameborder="0" …></iframe>
</div>

kanzitelli

version: '3'

services:
  reverse-proxy:
    image: traefik:v2.0
    container_name: traefik
    command: --api --providers.docker
    ports:
      - "6969:80"
      - "6970:8080"

letsjump

-- 1. Install ADB on your computer
-- 2. adb backup -noapk com.freestylelibre.app.it
-- 3. Decompress data with zlib support:
--    printf "\x1f\x8b\x08\x00\x00\x00\x00\x00" |cat - /tmp/data |gzip -dc >/tmp/out 
-- 4. go to apps/com.freestylelibre.app.it/f/
-- 5. open apollo.db and sas.db in a sqlite editor 
-- 6. copy notes.data into sas.db
-- 7. run this query to have a diary with sensor scans and notes:

SELECT strftime('%d/%m/%Y %H:%M:%S', datetime(timestampLocal/1000, 'unixepoch')), comment, glucoseValue, fastInsulinDose, slowInsulinDose, foodCarbs, foodType

bcherny

type None = {
  flatMap<U>(f: (value: null) => Option<U>): None
  getOrElse<U>(def: U): U
  isEmpty(): true
  map<U>(f: (value: null) => U): None
  nonEmpty(): false
  orElse<U>(alternative: Option<U>): Option<U>
}

type Some<T> = {

erikras

import React, { Component, PropTypes } from 'react'

class RichTextMarkdown extends Component {
  static propTypes = {
    input: PropTypes.shape({
      onChange: PropTypes.func.isRequired,
      value: PropTypes.string
    }).isRequired
  }

darklight721

Using MobX with decorators in React Native

The following instructions should work with React Native v0.32:

1. Install mobx libraries.

   npm install mobx --save
   npm install mobx-react --save

joostvanveen

# Get available disk space
df -h

# Get the top 10 biggest folders in the current directory
du -h --max-depth=1 | sort -rh | head -10

# Get the top 10 biggest folders in the current directory and their first child directories
du -h --max-depth=2 | sort -rh | head -10

# Get sizes of all folders in the current directory

gorangajic

update object

var state = {
    id: 1,
    points: 100,
    name: "Goran"
};

var newState = {

tobiasstrebitzer

{
  "name": "polymer-globals-behavior",
  "dependencies": {
    "polymer": "Polymer/polymer#~1.0.5"
  }
}