Newer alternative is at https://squid.diladele.com/ and my config(just changed dns server ips for work) (secret gist https://gist.github.com/Kambaa/2f189a70ef3bf26ad5410947bcfefb4d)

squid-server

An OLDER, simple working squid server for windows, not very secure, some config editing needed.

instructions

• unzip to a <YOUR_DIR>
• open <YOUR_DIR>/squid/etc/squid.conf file
• replace all <YOUR_DIR> with appropriate directory(that squid folder is in)
• go to https://www.web2generators.com/apache-tools/htpasswd-generator create htpasswd text according to given user and password (or https://hostingcanada.org/htpasswd-generator/ on mode field, select Apache specific salted MD5 (insecure but common))
• copy generated user pass info text to squid/etc/passwd file(replace with everything)
• open <YOUR_DIR>/squid/sbin folder in terminal
• use run.bat file or
  • run command below to create cache stuff(edit where your squid folder is and cd to it first)

.\squid.exe -z -f <YOUR_DIR>/squid/etc/squid.conf

• run command below to start cache server(or run the start.bat file in the main squid directory-edit where your squid folder is and cd to it first)

.\squid.exe -f <YOUR_DIR>\squid\etc\squid.conf -d 2

• use proxy like this:

<squid's running local ip address>:3128

USAGE

git

setup no auth:

git config --global http.proxy http://ip:port

setup with auth:

git config --global http.proxy http://username:password@ip:port

revert/reset setting:

git config --global --unset http.proxy

maven

add this to your settings.xml

<settings>
 ... OTHER SETTINGS ...
<proxies>
   <proxy>
      <id>worklaptopproxy</id>
      <active>true</active>
      <protocol>http</protocol>
      <host>YOUR IP ADDRESS</host>
      <port>3128</port>
      <username>user</username><!-- enter username here -->
      <password>pass</password><!-- enter password here -->
      <!-- <nonProxyHosts>www.google.com|*.example.com</nonProxyHosts> -->
    </proxy>
  </proxies>
</settings>

browsers

• use an addon Foxyproxy(My favorite, defining domain names and it uses proxy automatically),SwitchyOmega etc.
• add your proxy like <IP>:3128 (with user pass info)

other

• find proxy setup and set it to: <IP>:3128
• Running java apps (not tested) command line : java -Dhttp.proxyHost=YOURIP -Dhttp.proxyPort=3128 (from https://docs.oracle.com/javase/1.5.0/docs/guide/net/proxies.html)

Somethings to read about this:

• https://techencyclopedia.wordpress.com/2018/04/07/how-to-install-and-configure-squid-proxy-on-windows/
• https://stackoverflow.com/questions/28677228/using-proxy-server-for-java-application
• https://docs.oracle.com/javase/1.5.0/docs/guide/net/proxies.html
• https://www.baeldung.com/java-connect-via-proxy-server
• https://chrome.google.com/webstore/detail/proxy-switchyomega/padekgcemlokbadohgkifijomclgjgif/related?hl=en
• psf/requests#881
• https://elatov.github.io/2019/01/using-squid-to-proxy-ssl-sites/
• https://stackoverflow.com/questions/120797/how-do-i-set-the-proxy-to-be-used-by-the-jvm
• https://docs.oracle.com/javase/6/docs/technotes/guides/net/proxies.html
• https://stackoverflow.com/a/62311039
• https://gist.github.com/evantoli/f8c23a37eb3558ab8765