Open a H2 database :

 java -jar com.h2database.h2-2.1.214.jar

or squirrelSQL

add driver with com.h2database.h2-2.1.214.jar.

Default credentials

login : sa
password : password

UPDATE OCTOER 2022

If you want to quickly start the Restore process and don't care about having that option always enabled, then just fire up the Developer console on the browser and run this while on the Restore page

    var modelimport = new Ai1wm.Import();

var storage = Ai1wm.Util.random(12);
var options = Ai1wm.Util.form('#ai1wm-backups-form').concat({ name: 'storage', value: storage }).concat({ name: 'archive', value: 'REPLACE-WITH-ARCHIVE-NAME'});

// Set global params
modelimport.setParams(options);

// Start import
modelimport.start();

Limits the used bandwidth, specified in Kbit/s.

scp -l 1000 file user@remote:/path/to/dest/

Reminder classloader, classname :

Exit0.class.getSimpleName() = Exit0
Exit0.class.getCanonicalName() = com.gorki.Exit0
<instance>.getClass().getSimpleName() = 
<instance>.getClass().getCanonicalName() = null
<instance>.getClass().getName() = com.gorki.Exit0$1
<instance>.getClass().getTypeName() = com.gorki.Exit0$1
<instance>.getClass().getPackage().getName() = com.gorki
<instance>.getClass().isAnonymousClass() = true

With :

package com.gorki;

import java.util.ArrayList;
import java.util.Random;

public class Exit0 {

    public static void main(String... args) {

        Runnable t = new Runnable() {
            @Override
            public void run() {
            }
        };

        System.out.println("Exit0.class.getSimpleName() = " + Exit0.class.getSimpleName());
        System.out.println("Exit0.class.getCanonicalName() = " + Exit0.class.getCanonicalName());
        System.out.println("<instance>.getClass().getSimpleName() = " + t.getClass().getSimpleName());
        System.out.println("<instance>.getClass().getCanonicalName() = " + t.getClass().getCanonicalName());
        System.out.println("<instance>.getClass().getName() = " + t.getClass().getName());
        System.out.println("<instance>.getClass().getTypeName() = " + t.getClass().getTypeName());
        System.out.println("<instance>.getClass().getPackage().getName() = " + t.getClass().getPackage().getName());
        System.out.println("<instance>.getClass().isAnonymousClass() = " + t.getClass().isAnonymousClass());
    }
}

pop culture

merci sebsauvage (comment souvent)

Search for microsoft activation kit (official online download and installation)

 https://github.com/massgravel/

See licence key at

https://www.cjs-cdkeys.com

Best practices shell, to improve :

When printing error messages, please redirect to stderr.
Use echo 'Something unexpected happened' >&2 for this.

And also :

Use set -o xtrace, with a check on $TRACE env variable.

For copy-paste: if [[ "${TRACE-0}" == "1" ]]; then set -o xtrace; fi.
This helps in debugging your scripts, a lot. Like, really lot.
People can now enable debug mode, by running your script as TRACE=1 ./script.sh instead of ./script.sh.

The problem is most engineers don’t want to do operations work. 

So true ! I'm interested in. I want to know how OPs work. I don't want to do it every day :D

Test htaccess rules

Outil de comparaison voiture électrique/thermique :

https://evfootprint.org/simulator

Epub

Generate a self certificate without adding altName with the IP can lead to an error

The reason this error in java 1.8.0_181 is because this update includes security improvements for LDAP support

-Dcom.sun.jndi.ldap.object.disableEndpointIdentification=true

Java class to test SSL

Additional parameter :

 -Djavax.net.debug=ssl,handshake
 -Djavax.net.debug=ssl,manager
 -Djavax.net.debug=all

A lire
Architecture logicielle

DWService

# check that name is a valid variable name:
# note: this code does not support variable_name[index]
shopt -s globasciiranges
[[ "$name" == [a-zA-Z_]*([a-zA-Z_0-9]) ]] || exit

value='babibab'
eval "$name"='$value'  # carefully escape the right-hand side!
echo "$var_37"  # outputs “babibab”

Detect virtualized platform

systemd-detect-virt
hostnamectl
lshw -class system
dmidecode -s system-product-name

Pour avoir la description d'une méthode version bytecode :

import java.lang.reflect.Constructor;
import java.lang.reflect.Executable;
import java.lang.reflect.Method;
import java.util.concurrent.ThreadPoolExecutor;

public class ByteCodeDescriptor {

    public static void main(String... args) {

        Class clazz = ThreadPoolExecutor.class;

        String result=     ByteCodeDescriptor.getDescriptorForClass(clazz);
        System.out.println("class = " + result);

        for (Method m : ThreadPoolExecutor.class.getMethods()) {
            String resultM= ByteCodeDescriptor.getDescriptor(m);
            System.out.println("method = " + m);
            System.out.println("method result = " + m.getName() + resultM);
        }

        for (Constructor c :     ThreadPoolExecutor.class.getConstructors()) {
        String resultM= ByteCodeDescriptor.getDescriptor(c);
        System.out.println("constructor = " + c);
        System.out.println("constructor result = " + resultM);
    }

}

static String getDescriptorForClass(final Class c)
{
    if(c.isPrimitive())
    {
        if(c==byte.class)
            return "B";
        if(c==char.class)
            return "C";
        if(c==double.class)
            return "D";
        if(c==float.class)
            return "F";
        if(c==int.class)
            return "I";
        if(c==long.class)
            return "J";
        if(c==short.class)
            return "S";
        if(c==boolean.class)
            return "Z";
        if(c==void.class)
            return "V";
        throw new RuntimeException("Unrecognized primitive "+c);
    }
    if(c.isArray()) return c.getName().replace('.', '/');
    return ('L'+c.getName()+';').replace('.', '/');
}

static String getDescriptor(Executable e) {
    String s = "(";
    for (final Class c : e.getParameterTypes())
        s += getDescriptorForClass(c);
    s += ')';
    if (e instanceof Method) {
        Method m = (Method) e;
        return m.getName() + s + getDescriptorForClass(m.getReturnType());
    } else if (e instanceof Constructor) {
        Constructor c = (Constructor) e;
        return "<init>" + s + getDescriptorForClass(void.class);
    }
    throw new RuntimeException("Unrecognized primitive "+e);
}
}

Reminder

python3 -m http.server 5051

Notes for openssl

Private key :

# Add a password to a PEM private key file
openssl rsa -aes256 -in unprotected.pem -out protected.pem -passout "pass:toto"
# Read a PEM private key file with password
openssl rsa -in  password.pem -passin "pass:toto"
openssl rsa -in  password.pem -passin "file:password.txt"

Certificate :

# Read a certificate PEM file
openssl x509 -in certificate.pem
# Fingerprint for the certificate
openssl x509 -noout -in certificate.pem -sha256 -fingerprint
# Certificate chain
openssl x509 -noout -subject -issuer -in  certificate.pem

Verify certificate

# sign fil with private key
openssl dgst -sha256 -sign tstpri.pem -out tst.sig fil
# verify the signature with matching public key
openssl dgst -sha256 -verify tstpub.pem -signature tst.sig fil

File extensions can be (very) loosely seen as a type system.

.pem

a base64 encoding with header and footer lines. 
The contents of the PEM are detailed in the header and footer line 
[Examples](https://stackoverflow.com/questions/5215771/how-can-i-check-if-the-certificate-file-i-have-is-in-pem-format)
 CRT
 -----BEGIN CERTIFICATE-----
 -----END CERTIFICATE-----
 PEM
 -----BEGIN RSA PRIVATE KEY-----
 -----END RSA PRIVATE KEY----

.der

as PEM this is binary encoding method, conversion : 
openssl x509 -in example.pem -out example.der -outform DER

.key

can be any kind of key, but usually it is the private key.
OpenSSL can wrap private keys for all algorithms (RSA, DSA, EC) in a generic and standard PKCS#8 structure 
the encoding could be PEM or DER, both can protect the key with password-based 

.crt or .cer

stands simply for certificate, usually an X509v3 certificate, 
the encoding could be PEM or DER
a certificate contains the public key, but it contains much more information (most importantly the signature by the Certificate Authority over the data and public key, of course).

.csr or .req or sometimes .p10

stands for Certificate Signing Request as defined in PKCS#10; 
the encoding could be PEM or DER
it contains information such as the public key and common name required by a Certificate Authority to create and sign a certificate for the requester, 

.p12 or .pfx

is a PKCS#12 defined key store, commonly password protected. 
It can contain trusted certificates, private key(s) and their certificate chain(s), but also other information such as secret keys and (
p12 is usually binary / DER encoded. 

.crl

is a Certificate Revocation List which is defined within the X.509v3 certificate specifications, and this is usually DER encoded as well.