breakpo: 2023

web2mail.cloud - A service to get a webpage as attachment by email

https://www.web2mail.cloud is a service that allows you to send an email with a any website at the subject and get a reply email with this webpage as an image, jpg, png or pdf.

You can even set the width and height.

https://www.web2mail.cloud

Bypassing the error by "go get" "tls: failed to verify certificate: x509: certificate signed by unknown authority"

When I was trying to download dependencies for my go project in an old Ubuntu machine I was getting this error all the time:

"go: gopkg.in/alexcesaro/quotedprintable.v3@v3.0.0-20150716171945-2caba252f4dc: Get "https://proxy.golang.org/gopkg.in/alexcesaro/quotedprintable.v3/@v/v3.0.0-20150716171945-2caba252f4dc.mod": tls: failed to verify certificate: x509: certificate signed by unknown authority"

Which the main part of it was go get failing to authenticate: "tls: failed to verify certificate: x509: certificate signed by unknown authority"

I tried many things but couldn't make it work until I found the way:

export GOINSECURE="proxy.golang.go"

This will tell go get to ignore certification validity.

Then

export GOPROXY=direct

This will tell go get to by pass proxy

Then

git config --global http.sslverify false

And only after those I could run again:

go get

And it worked

List of software and apps that does not require registration and just works

List of software and apps that does not require registration and just works out of the box without too many ads and without need to registrations. The list of applications for Android and Linux desktop that just do the work they need to do. Nothing more. Nothing less.

K-9 Email Mail for Android
Otomusic - music mp3 player application for Android

Writing a json to smtp email proxy in go (golang) json2smtp

I wrote a json2smtp proxy server that can be self hosted in Go (golang)

See here:

https://www.c2kb.com/json2smtp

https://github.com/caviv/json2smtp

The reason why I needed to write an email proxy was because I was called to do some maintenance on an old legacy system. This system was running on Windows Server 2012, with php version 5.5.6 and Apache 2.4. Very old versions of software. The system was sending emails using the php smtp package and old libssl.dll which supports only TLSv1.0. The smtp service they were using (AWS SES Simple Email Service) has recently dropped the support for SMTP connection via TLS version 1.0. Now in order to support TLS v1.2 for emails on smtp I have to upgrade the whole system. Windows version, php version, Apache version and more - this would have taken me a very long time with many obstacles on the way.

Amazon support: https://docs.aws.amazon.com/ses/latest/dg/security-protocols.html

The solution I have chosen was to write this proxy, so calls from the php to send email will be sent as JSON object with attachments to the json2smtp proxy and from there will be sent to the smtp server using TLS 1.2

I have checked some other options that were recommended by Chat-GPT and Bard. But all of them were actually much more complicated to implement than writing my own solution which took me less than a few hours to code. If you know other similar tools and services please let me know.

Here are the tools that did not work for me:

MailSlurp is a cloud-based email proxy that allows you to receive emails in JSON format. It also provides a number of other features, such as the ability to create and manage email addresses, send emails, and track email activity. | This is an online service that costs money.

SMTP2GO is a cloud-based email service that provides a variety of features, including email proxying. It allows you to receive emails in JSON format and send emails through its own SMTP servers. | This is an online service that costs money.

Mailgun is another cloud-based email service that provides email proxying. It allows you to receive emails in JSON format and send emails through its own SMTP servers. | This is an online service that costs money.

SendGrid is a cloud-based email service that provides email proxying. It allows you to receive emails in JSON format and send emails through its own SMTP servers. | This is an online service that costs money.

In addition to these cloud-based services, there are also a number of self-hosted email proxy tools that can be used. Some of these tools include:

Postfix is a popular open-source mail server that can be used as an email proxy. It can be configured to receive emails in JSON format and send emails through its own SMTP servers. | might be ok but very hard to configure.
Exim is another popular open-source mail server that can be used as an email proxy. It can be configured to receive emails in JSON format and send emails through its own SMTP servers. | might be ok but very hard to configure.
Mailcow Dockerized is a Docker image that contains a number of email server components, including Postfix, Dovecot, and MySQL. It can be configured to receive emails in JSON format and send emails through its own SMTP servers. | Couldn't make it work

An email proxy: input: json, output: smtp call

For a legacy project I needed to have a proxy email that reads json input and execute a smtp calls in order to send emails. So I created a small proxy for emails in go (golang)
See the code on github: https://github.com/caviv/json2smtp

Download json2smtp binaries executables

Ubuntu linux: json2smtp
Windows amd64: json2smtp-amd64.exe

How it works:

Simple calling diagram:
Simple architecture of calling the json2smtp email proxy server with json and smtp calls

The json struct object

Simple object:


		curl -X POST \
 -H "Content-Type: application/json" \
 -d '{ \
"from": "john doe <john@example.com&rt;", \
"to": ["kermit@muppets.com", "oneperson@example.com"], \
"cc": ["email1@example.com"], \
"bcc": ["secret@example.com"], \
"subject": "email subject line", \
"message": "message body in text/html to be sent", \
"attachments": {"filename.pdf": "base64 file encoded", 
                "anotherfilename.txt": "base64 file encoded"}, \
 }' \
 http://localhost:8080/

Full object with smtp data:


		curl -X POST \
 -H "Content-Type: application/json" \
 -d '{ \
"from": "john doe <john@example.com&rt;", \
"to": ["kermit@muppets.com", "oneperson@ex", \
"to": ["kermit@muppets.com", "oneperson@example.com"], \
"cc": ["email1@example.com"], \
"bcc": ["secret@example.com"], \
"subject": "email subject line", \
"message": "message body in text/html to be sent", \
"attachments": {"filename.pdf": "base64 file encoded", 
                "anotherfilename.txt": "base64 file encoded"}, \
"smtphost": "smtp.example.com - optional parameter", \
"smtpport": 587 - optional paramater, \
"smtpuser": "username - optional parameter", \
"smtppassword": "password - optional parameter" \
 }' \
 http://localhost:8080/

Attachments

In order to send attachments with your json email struct you need to construct an object of base64 encoded string of your binary file.

How to install email proxy server:

Download the code and run it


	git clone https://github.com/caviv/json2smtp.git
go run ./
go run ./ --help

Build and compile

Download the code compile it and run with help command

git clone https://github.com/caviv/json2smtp.git
go build ./
./json2smtp --help

Execute smtp2json emal proxy and samples

Command line help:

json2smtp utility https://www.c2kb.com/json2smtp v1.0.1 2023-11-13
Get json input and calls smtp - function as a json to smtp proxy
Options:
  -port int
    	the port to listen on (default 8080)
  -smtphost string
    	smtp host, e.g. smtp.example.com
  -smtpoverride
    	true - allows to pass smtp parameters in the json call,
    	       false will always use the config smtp data (default true)
  -smtppassword string
    	password for the smtp user
  -smtpport int
    	the port to listen on (default 587)
  -smtpuser string
    	username for the smtp

Example:


	json2smtp --port=8200 --smtphost='smtp.example.com' 
          --smtpport=587 --smtpuser='username' 
          --smtppassword='password'
          --smtpoverride=false

Run service in the background:


	nohup json2smtp --port=8200 --smtphost='smtp.example.com'
                --smtpport=587 --smtpuser='username'
                 --smtppassword='password' >> logfile.log 2>&1 &

Simple execute smtp2json service:

In this way the calling client will have to pass the smtp server details in each call because we don't set the smtp default server for the proxy. The default port to listen on is 8080.

json2smtp

Recommended architecture to run the service:

Calling json2smtp proxy behind a caddy web server for https / tls

Libraries used

This external libraries are used in the project:

require gopkg.in/mail.v2 v2.3.1
require gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0

Taking a screenshot and creating thumbnail of webpage html as an image via command line

There are a few options to take screenshot of a webpage or save a webpage as an image on the disk via the command line. This can allow you to create a thumbnail of a web site easily by one command on the terminal.

Using chrome to save a webpage as an image:

chrome --screenshot=google.png --headless --window-size=1024,768 https://www.google.com/

Using cutycapt to screenshot a webpage:

https://cutycapt.sourceforge.net/

Using webkit2png to create site thumbnail:

https://paulhammond.org/webkit2png

You can also use Midori browser

Linux Ubuntu Installing and Using Fake Camera Stream

If you wish to create a virtual camera in Linux and stream "fake" videos during calls:

To install the loopback camera:

sudo apt update sudo apt install v4l2loopback-dkms v4l2loopback-utils

To add the loopback camera module:

sudo modprobe v4l2loopback card_label="My Fake Webcam" exclusive_caps=1

sudo modprobe v4l2loopback devices=1 video_nr=1 card_label='MyWebCam' exclusive_caps=1

Now to stream the video:

First find the list of videos device available:

v4l2-ctl --list-devices

You can check the videos by playing:

ffplay /dev/videoX ffplay Rick_Astley_Never_Gonna_Give_You_Up.mpg

Now you can stream the video to the free one:

ffmpeg -re -i Rick_Astley_Never_Gonna_Give_You_Up.mpg -map 0:v -f v4l2 /dev/videoX

ffmpeg -stream_loop -1 -re -i video.mp4 -vcodec rawvideo -threads 0 -f v4l2 /dev/videoX

To remove the module from the kernel:

sudo modprobe --remove v4l2loopback

Software for streaming:

sudo apt-add-repository ppa:obsproject/obs-studio
sudo apt-get update
sudo apt-get install ffmpeg obs-studio

Go (golang) howto not to export fields of a struct when Unmarshal to json object

Use:

typedef MyData struct {

Data string `json:"data"`

FieldName *int64 `json:"-"`

}

Adding the `json:"-"` will make the Unmarshal command disregard this field

Cleaning and resizing VM VirtualBox VDI Virtual Machine Disk

You have to do the following steps:

Run defrag in the guest (Windows only)
Nullify free space:

With a Linux Guest run this:

dd if=/dev/zero of=/var/tmp/bigemptyfile bs=4096k ; rm /var/tmp/bigemptyfile
Or:

telinit 1
mount -o remount,ro /dev/sda1
zerofree -v /dev/sda1
With a Windows Guest, download SDelete from Sysinternals and run this:

sdelete.exe c: -z
(replace C: with the drive letter of the VDI)

Shutdown the guest VM

Now run VBoxManage's modifymedium command with the --compact option:

With a Linux Host run this:

vboxmanage modifymedium --compact /path/to/thedisk.vdi
With a Windows Host run this:

VBoxManage.exe modifymedium --compact c:\path\to\thedisk.vdi
With a Mac Host run this:

VBoxManage modifymedium --compact /path/to/thedisk.vdi
This reduces the vdi size.

https://superuser.com/questions/529149/how-to-compact-virtualboxs-vdi-file-size

Some notes about caddy webserver installation on Linux

caddy

https://caddyserver.com/docs/install#debian-ubuntu-raspbian

sudo apt update

sudo apt install -y debian-keyring debian-archive-keyring apt-transport-https

curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' | sudo tee /etc/apt/trusted.gpg.d/caddy-stable.asc

curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/debian.deb.txt' | sudo tee /etc/apt/sources.list.d/caddy-stable.list

sudo apt update

sudo apt install caddy

# the code sits in /var/www

# create link to the local directory

ln -s /var/www/ /home/xxx/myprojects/web

# set the user to be xxx and the group caddy

sudo chown -R xxx:caddy ./www

# add us to caddy groups

sudo usermod -a -G caddy xxx

sudo usermod -a -G www-data xxx

Install php-fpm

sudo apt install php-cli php-fpm php-mysql php-mbstring php-curl

https://www.howtoforge.com/tutorial/ubuntu-caddy-web-server-installation/

configure caddy with php

sudo nano /etc/php/8.1/fpm/pool.d/www.conf

#change users to caddy (user, group, listen.owner, listen.group)

#take the socket name: listen = /run/php/php8.1-fpm.sock

nano php.ini # set E_ALL view all errors

sudo systemctl restart php8.1-fpm

#set socket in Caddyfile: php_fastcgi unix//run/php/php8.1-fpm.sock

sudo service caddy stop && sudo service caddy start

Caddyfile
website.com {
#:80 {
tls /var/www/fullchain.pem /var/www/privkey.pem

# Set this path to your site's directory.
root * /var/www/website.com
php_fastcgi unix//run/php/php7.4-fpm.sock

# Enable the static file server.
# file_server
rewrite /symbol/* s.php?s={path}
# rewrite /symbol/ {
# r ^/(\w+)/?$
# to /symbol.php?symbol={1}
# }
file_server

encode gzip

log {
output file /var/log/caddy/example.com.access.log {
roll_size 3MiB
roll_keep 5
roll_keep_for 48h
}
format console
}
# Another common task is to set up a reverse proxy:
# reverse_proxy localhost:8080

# Or serve a PHP site through php-fpm:
# php_fastcgi localhost:9000

#RewriteRule ^symbol/jscss/([^/]*)\.([^/]*)$ /jscss/$1.$2 [L] # no need for those since we used <base href="../" />
#RewriteRule ^symbol/images/([^/]*)\.([^/]*)$ /images/$1.$2 [L]
#rewrite /symbol/* / symbol.php?symbol={query}
}

I had the same problem whith my docker php-fpm and I fixed it by modifing parameters

in these files: /usr/local/etc/php-fpm.d/www.conf /usr/local/etc/php-fpm.d/www.conf.default

The new parameters are :

pm = dynamic
pm.max_children = 25
pm.start_servers = 10
pm.min_spare_servers = 5
pm.max_spare_servers = 20
pm.max_requests = 500

- ADD how to enabled logs in PHP

Linux terminal shell command line to show a list of just the files in the directory

find . -type f

php8 COM Exception Type Mistmtach in paramater #0 when calling MS Word COM object SaveAs

I saw this:

https://bugs.php.net/bug.php?id=73605

When calling $word->SaveAs($filename, 8);

You should change to $word->SaveAs($filename, new variant(8, VT_I4);

php 8 using ldap connectivity configuring php.ini and apache2.4

Got an error that ldap_connect is not a recognize function to use with apache 2.4, php 8 on windows

Here is a solution:

Enable extension=ldap in the php.ini

Copy .dll files from the php installation directory into the apache/bin installation directory

Please note, ldap_sort function was deprecated

Linux Ubuntu Changing the datadir (data directory) of mysql

mysqld.cnf

datadir = /new/data/dir

mysqld --user=mysql --initialize

innodb_flush_log_at_trx_commit= 0
ssl=0 # (5.7 community (self built) might not use SSL for cases. 8.0 always use ssl by default, might be slower)
innodb_doublewrite_pages=120 # (if doublewrite enabled for recent 8.0.x "on HDD")
innodb_undo_log_truncate=OFF
innodb_log_writer_threads=OFF

plugin-load-add=auth_socket.so
auth_socket=FORCE_PLUS_PERMANENT

sudo systemctl stop apparmor

sudo systemctl disable apparmor

sudo mysqldump --master-data=1 --flush-logs --single-transaction --routines --quick --all-databases > db20230116_1852.sql

CREATE USER 'XXXXX'@'%' IDENTIFIED WITH mysql_native_password BY 'XXXXXX';
GRANT ALL PRIVILEGES ON *.* TO 'XXXXX'@'%' WITH GRANT OPTION;
FLUSH PRIVILIGES;

mysql linux client get stuck on command line connecting mysql server 8.0

use

mysql --ssl-mode=DISABLED -p

breakpo