cpursley

PostgreSQL is Enough

• Simplify: move code into database functions
• Just Use Postgres for Everything
• PostgreSQL is the worlds’ best database
• Postgres is eating the database world
• Hacker News discussion

Background and Cron Jobs

luizomf

Upscale 1080p to 4k using ffmpeg

Just use the command below:

ffmpeg -i INPUT_FILE \
  -vf scale=3840x2160:flags=lanczos \
  -c:v libx264 \
  -crf 13 \
 -c:a aac -b:a 512k \

ryanflorence

Everything I Know About UI Routing

Definitions

1. Location - The location of the application. Usually just a URL, but the location can contain multiple pieces of information that can be used by an app
   1. pathname - The "file/directory" portion of the URL, like invoices/123
   2. search - The stuff after ? in a URL like /assignments?showGrades=1.
   3. query - A parsed version of search, usually an object but not a standard browser feature.
   4. hash - The # portion of the URL. This is not available to servers in request.url so its client only. By default it means which part of the page the user should be scrolled to, but developers use it for various things.
   5. state - Object associated with a location. Think of it like a hidden URL query. It's state you want to keep with a specific location, but you don't want it to be visible in the URL.

bbennett36

import pandas as pd
import numpy as np

def test_cutoffs(start_amount, start_price, buy_fee, sell_fee, end_price):
    bought_fee = start_amount*buy_fee
    bought_amt = (start_amount-bought_fee) / start_price
    
    sold = bought_amt*end_price
    sold_fee = sold*sell_fee
    sold = sold-sold_fee

crpietschmann

# Generate Private Key and Certificate using RSA 256 encryption (4096-bit key)
openssl req -x509 -newkey rsa:4096 -keyout privatekey.pem -out certificate.pem -days 365
# Alternatively, setting the "-newkey" parameter to "rsa:2048" will generate a 2048-bit key.

# Generate PKCS#12 (P12) file for cert; combines both key and certificate together
openssl pkcs12 -export -inkey privatekey.pem -in certificate.pem -out cert.pfx

# Generate SHA256 Fingerprint for Certificate and export to a file
openssl x509 -noout -fingerprint -sha256 -inform pem -in certificate.pem >> fingerprint.txt

francisrstokes

import React from 'react';

export class StateDispatcher extends React.Component {
  constructor(props) {
    super(props);
    this.state = props.state || {};
    this._dispatch = this.dispatch.bind(this);
  }

  dispatch(action) {

davideicardi

Avro serialization

There are 4 possible serialization format when using avro:

• Avro Json encoding
• Avro Data Serialization (https://avro.apache.org/docs/current/spec.html#Data+Serialization) Binary format with an header that contains the full schema, this is the format usually used when writing Avro files
• Avro Single Object Encoding (https://avro.apache.org/docs/current/spec.html#single_object_encoding) Binary format with an header with only the fingerprint/id of the schema, this it the format used by Kafka (see this
• Avro Binary Encoding (https://avro.apache.org/docs/current/spec.html#binary_encoding)

sergiobd

# Script to convert a list of files using ffmpeg and powershell. This example converts to .ogv files (theora/vorbis as video/audio codecs)
# Please note that, if you havent done so, you should set the execution policy of powershell in order to be able to run this script.
# The easiest way to run this script without messing to much with execution policies is to set it for a single powershell session:
# powershell.exe -ExecutionPolicy Unrestricted
# Check: https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_execution_policies

$filenames = "1","2", "3", "4", "5","6","7"
$filepath = "C:\Users\Oculus\Documents\Videos\Menu\"
$extension = ".mp4"

chukaofili

apiVersion: v1
kind: Namespace
metadata:
  name: echoserver
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: echoserver
  namespace: echoserver

elizarov

// Inspired by http://akarnokd.blogspot.ru/2017/09/rxjava-vs-kotlin-coroutines-quick-look.html
// Requires Kotlin 1.2.30 or later
// Uses kotlinx.coroutines library

import kotlinx.coroutines.experimental.*
import kotlin.system.*

suspend fun f1(i: Int): Int {
    println("f1 attempt $i")
    delay(if (i != 3) 2000 else 200)