1 déc. 2017

[Code] Équivalence Bash vs Powershell


Excellent tableau comparatif entre Bash (scripting shell) et PowerShell (scripting PowerShell
windows) qui peut être intéressant de voir si on connait l'un des deux langages et que l'on souhaite se mettre à l'autre !



Source : http://cecs.wright.edu/~pmateti/Courses/233/Labs/Scripting/bashVsPowerShellTable.html


bashPowerShellDescription
Scripting Basics
Put a "shebang" at the beginning of the file: 
#!/bin/bash

Change permissions on script file to allow execution.
Give the file a ps1 extension. For downloaded scripts, unblock the file under file properties in Windows Explorer.Steps for making scripting files run. In PowerShell, the first time you do scripting, you will need to set the appropriate security settings: run PowerShell as administrator and type set-executionpolicy remotesigned.
source (or) ..shell built-in: execute the commands in a file
echo Stringecho String (or)
Write-Host String
Prints String to the screen. In PowerShell, Write-Hostforces the output to the screen instead of being a return value.
var=0
(No spaces around =)
$var = 0Creates a variable $var. In BASH, do not put whitespace around the equals sign, and do not use a $ in the variable assignment.
let var=$var+5 (or)
var=$(( $var + 5 ))
$var += 5Add 5 to $var
commentcommentA comment
Strings
= !=-eq -ne -ceq -cneString comparisons. In BASH, be sure the strings litereals are in quotes.
"" | gmGet a list of non-static string members
[string] | gm -staticGet a list of static string members
${string#text_to_remove}string.TrimStart("characters")Removes the specified characters/text from the beginning of the string.
${string%text_to_remove}string.TrimEnd("characters")Removes the specified characters/text from the end of the string.  Suppose $fnm == helloThere.txt; then ${fnm%.???} is helloThere
Pattern Matching
grepselect-stringprint lines matching a pattern
sed-replaceperforms string transformations
Booleans and Conditions
true  false$true  $falseBoolean literals
-lt -gt -le -ge -eq -ne-lt -gt -le -ge -eq -neArithmetic relational operators
-likeTrue if a string matches a wildcard pattern
-matchTrue if a string matches a regular expressions
Where-Object { condition }Used to filter input by a condition. Remember that $_ refers to the current object being tested.
-z $var$var -eq $nullTrue if $var is null
-n $var$var -ne $nullTrue if $var is not null (contains one or more characters)
-o -a-or -andLogical or and and
-e fileTest-Path fileTrue if file exists.
! -e file! (Test-Path file)True if file does not exist.
-d filefile.PSISContainerTrue if file is a directory. In PowerShell, if file is not a file variable, be sure to get the file object first with gi.
-s fileTrue if file exists and has a size greater than zero.
file1 -nt file2True if file1 is newer (according to modification date) than file2
file1 -ot file2True if file1 is older (according to modification date) than file2
Control Structures
if [ condition ]
then
   codeblock
fi
if (condition) {
   codeblock
}
If statement. In BASH, be sure to leave a space between the condition and the bracket.
if [ condition ]
then
   codeblock
elif [ condition ]
then
   codeblock
else
   codeblock
fi
if (condition) {
   codeblock
}
elseif (condition) {
   codeblock
}
else {
   codeblock
}
If - else if - else statement
var=0
while [ $var -lt 10 ]
do
   echo $var
   var=$(( $var + 1 ))
done
$var = 0
while ($var -lt 10) {
   echo $var
   $var++
}
Prints numbers 0 through 9.
for ((i=0; i < 10; i++)) do
   echo $i
done
for ($i=0;$i -lt 10; $i++)
{
   echo $i
}
Prints numbers 0 through 9.
for var in $array
do
   codeblock
done
foreach ($var in $array)
{
   codeblock
}
For each loop
continue  breakcontinue  breakLoop controls: continue stops current loop iteration and begins the next; break exits the loop currently being executed.
basename filefile.nameThe name of file without the path. In PowerShell, remember to first get the file object.
dirname filefile.directorynameThe name directory file is in. In PowerShell, remember to first get the file object.
stat -c%s $file (or)
$(stat -c%s $file)
file.lengthThe number of bytes in file. In PowerShell, remember to first get the file object.
file.LastWriteTimeThe last modified time for file. Remember to first get the file object.
files=`ls` (or)
files=$(ls) (or)
files=*
$files = Get-Item *Store a list of the files in the current working directory in $files. In PowerShell, check out the -exclude flag as well as the Get-ChildItem cmdlet.
|  >  >>  2>  2>>|  >  >>  2>  2>>Piping, output and error redirection. In BASH, output redirected to /dev/null is gone. In PowerShell, output redirected to $null is gone.
printArg()
{
   echo $1
}
function printArg
{
   param ($p1)
   echo $p1
}
function to print the first argument to the screen.
return_five()
{
   return 5
}

return_five
echo $?
function return_five
{
   echo 5
  (or)  return 5
}

$value = return_five
echo $value
Function returns 5, which is printed after the function call. In PowerShell, any output in a function that is not caught is returned. The return statement merely ends the function. The return value of a BASH function is stored in the variable $?.
File Information/Operations
lsListing of files. For bash, learn the options of -lisa, -r, -R.
lsListing of files. For PowerShell, learn -f, -r, -filter,and -exclude
treetreeGraphically displays the directory structure of a drive or path.
catcatList the contents of a file on the stdout
moremoreList the contents of a file on the stdout, pausing after each page
mkdirmkdirCreates a directory.
rmdirrmdirDeletes a folder if it is empty
pwdpwdprint working directory
cdcdChange the current directory to the one given as argument.
pushdpushdSaves the current directory name on the stack, and then cd's the one given as argument.
popdpopdPop off the top-most name on the stack, and then cd to it
mvmvMoves or renames files. In PowerShell, check out the -force and -WhatIf flags. In BASH, check out the -f flag.
cp -rcp -rCopies files and directory trees recursively.
cpcpCopies files. In PowerShell, check out the -force and -WhatIf flags. In BASH, check out the -f flag.
rmrmDeletes a file. Check out the -r flag. In PowerShell, check out the -force and -WhatIf flags. In BASH, check out the -f flag.
catcatshow the contents of each file in sequence
moremorepagination
rmrmRemove files
lnLink (hard or soft) to an existing file.
mklinkLink (hard or soft) to an existing file. Type cmd /c mklinkto use it in PowerShell
chmodattribChange file permissions/attributes
icaclsDisplays or modifies access control lists (ACLs) of files
chownicaclsChange ownership of a file. In PowerShell, multiple steps are necessary
umaskget/set the file mode creation mask; packed vector of bits controlling the initial permissions on a newly created file
dumeasureDisk space Used. In PowerShell, try gci . -r | measure -property length -sum
wcMeasure-Objectword count, etc.
odOctal dump of file content. Almost always used with -x for hexadecimal dump
trTranslate/substitute characters; useful in improving interoperability
assocList associations of commands with extensions. Type cmd /c assoc to use it in PowerShell
fileHeuristically determine the type of file content
grepselect-stringSearch for a string in a file's content. For now, learn it without regexp.
findgciLocate a file. By name, etc. For now, learn it without regexp.
whichGives the full path name of a command
whereGives the full path name of a command.  Type cmd /c where to use it in PowerShell
diffdiffList the differences between two text files
cmp, diffcompare, diffshow the differences between two files
gci . -r | sort length -descending | select -first 10get a list of the 10 largest files in the current directory (recursive)
vivimA powerful text editor. For now, learn to edit simple text files with it.
kate, leafpadnotepadSimple text editors.
emacsemacsA very powerful multi-purpose text editor. For now, learn to edit simple text files with it.
Processes
timeMeasure-Commandtimes commands, etc.
pspsshows current processes
gps | sort ws | select -last 5Get a list of the 5 processes using the most memory
gsv | where {$_.Status -eq "Stopped"}Get a list of stopped services
toplike ps, but with continuous updates
bgplace a STOPped process in the background
fgbring a backgrounded process to foreground
killkillkills a running program
ltraceshow lib calls made
straceshow sys calls made
System
manmanshow reference pages
setsetset the values of shell variables
setgvget and show the values of shell variables
envls env:\lists the current environment variables
$PATH$env:paththe search path
linksWWW/News/Mail browser
sftp, filezilla filezillatransfer files securely to/from a remote machine
ssh, putty sshclient, puttyremote login securely
wwho is on the system, and what they are doing
dfgdrshow mounted volumes, etc.

[Elasticsearch] installer et configurer Shield

Shield est un plugin fournissant une couche de sécurité d'Elasticsearch.
Dans les versions plus récente d'Elasticsearch Shield est embarqué dans X-PACK

1) Pré-requis

  • Java 7 or later
  • Elasticsearch 2.4.4
  • Elasticsearch License 2.4.4 plugin
  • Kibana 
  • CentOS 7.1

2) Installer le plugin Shield

Préalablement télécharger la licence 2.4.4 et le plugin shield 2.4.4
https://download.elastic.co/elasticsearch/release/org/elasticsearch/plugin/license/2.4.4/license-2.4.4.zip
https://download.elastic.co/elasticsearch/release/org/elasticsearch/plugin/shield/2.4.4/shield-2.4.4.zip

Se positionner dans le répertoire de /usr/share/elasticsearch/bin
# ./plugin install file:///path/to/file/license-2.4.4.zip
# ./plugin install file:///path/to/file/shield-2.4.4.zip

3) Etat des lieux post-install

Après l'installation le répertoire d'installation de shield se trouve ici :
/usr/share/elasticsearch/plugins/shield/
automaton-1.11-8.jar
config
LICENSE.txt
NOTICE.txt
plugin-descriptor.properties
plugin-security.policy
shield-2.4.4.jar
unboundid-ldapsdk-2.3.8.jar
et les binaires :
/usr/share/elasticsearch/bin/shield/
esusers
esusers.bat
migrate
migrate.bat
syskeygen
syskeygen.bat

4) Configuration Shield

4.1) Créer un compte utilisateur Admin
# ./bin/shield/esusers useradd es_admin -r admin
4.2) Restart elasticsearch
# systemctl restart elasticsearch
4.3) Tester l'authentification
# curl -u es_admin -XGET 'http://localhost:9200/'

Bibliographie:

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