paveltimofeev

Powershell Hints & Tricks

Convert hex to bytes, bytes to hex

function ConvertTo-Hex([byte[]]$bytes)
{
    return ($bytes | % { $_.ToString("X2") }) -join ""
}

function ConvertTo-Bytes([string]$hex)

paveltimofeev

Bash hints, tips & tricks

Exit on Error

set -e
set -o pipefail

# -e (errexit): Abort script at first error, when a command exits with non-zero status (except in until or while loops, if-tests, list constructs)
# In case script is calling subscript inside, the pipefail option can be useful.
# -o pipefail: Causes a pipeline to return the exit status of the last command in the pipe that returned a non-zero return value.

paveltimofeev

cls

$text = "Hello <color clr=`"green`">World</color>"
write-host $text

$tag=$false
$text.ToCharArray() | % { 

    if(!$tag){ $tag = $_ -eq "<"  }
    

paveltimofeev

<?xml version="1.0" encoding="utf-16"?>
<StorableColorTheme xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <Keys>
    <string>ErrorForegroundColor</string>
    <string>ErrorBackgroundColor</string>
    <string>WarningForegroundColor</string>
    <string>WarningBackgroundColor</string>
    <string>VerboseForegroundColor</string>
    <string>VerboseBackgroundColor</string>
    <string>DebugForegroundColor</string>

paveltimofeev

Batch (CMD) hints, tips & tricks

"try-catch" for bat-files

my-command with parameters && (
  
  echo - my-command completed successfuly

  (call)
) || (

paveltimofeev

Good storing passwords' hashes strategies

Do not store users' passwords in plain text, store hash of password instead. But only hashing is not enough, use one of these techniques, to make your users' data more protected:

• simple way:

passwordHash = hash( hash(passwd) + salt )

• better one - will produce different hashes for users with the same passwords:

paveltimofeev

param(
    [Parameter(Mandatory=$true)]
    $source,
    [Parameter(Mandatory=$true)]
    $output,
    $header = "/// © Pavel Timofeev",
    $excludes = @("AssemblyInfo.cs", "*.Designer.cs", "TemporaryGeneratedFile_*" ),
    $copyAsIs = @(),        # list of filemasks that should be copy as is without merge
    $addFileNames = $false, # add names of src files 
    $leftComments = $false, # remove line commented with //

paveltimofeev

Fitnesse Hints &Tricks

Case Sensitive regexp for FitNesse:

Use =~/(?i: ... )/

-|script|
|check| eval| "CaseInsensitive"| =~/caseinsensitive/   | # fail
|check| eval| "CaseSensitive"  | =~/(?i:casesensitive)/| # success

paveltimofeev

Nginx hints, tips & tricks

Reverse Proxy with Caching

nginx.com example
nginx-caching

http {
    proxy_cache_path  /data/nginx/cache  levels=1:2  keys_zone=STATIC:10m  inactive=24h  max_size=1g;
 server {

paveltimofeev

var os = require("os");

//Create function to get CPU information
function cpuAverage() {

  //Initialise sum of idle and time of cores and fetch CPU info
  var totalIdle = 0, totalTick = 0;
  var cpus = os.cpus();

  //Loop through CPU cores