Editing Test connectivity for the web service (section)

=== How to connect to the web service ===

If the service is the web server: 
* (1) Open the browser, (2) Type the address: {{kbd | key = <nowiki>http://127.0.0.1</nowiki> }} or {{kbd | key =<nowiki>http://the.domain</nowiki>}}

* Linux lynx command: 
*# (optional if lynx was not installed) {{kbd | key = <nowiki>yum install lynx</nowiki>}} for CentOS / {{kbd | key = <nowiki>sudo apt-get install lynx</nowiki>}} for Ubuntu<ref>[http://www.addictivetips.com/ubuntu-linux-tips/install-and-use-lynx-on-ubuntu/ Install and Use Lynx Browser on Ubuntu]</ref>
*# {{kbd | key = <nowiki>lynx http://127.0.0.1</nowiki>}} <ref>[http://lynx.isc.org/lynx2.8.7/lynx2-8-7/lynx_help/Lynx_users_guide.html Lynx Users Guide v2.8.7]</ref> for {{Linux}}

* telnet command
*# {{kbd | key = telnet 127.0.0.1 <PORT>}} e.g. {{kbd | key = telnet 127.0.0.1 80}} or {{kbd | key = telnet the.domain 80}}
*# (after telnet-ed the web 80 port, key in) {{kbd_plus | key1 = get | key2 = SPACE}}<ref>[http://www.simplescripts.de/http-check-port-80-telnet-command.htm HTTP Check Port 80 with the Telnet Command]</ref>

* curl<ref>[https://curl.se/docs/manpage.html curl - How To Use]</ref>: {{kbd | key = <nowiki>curl -vL http://IP:Port</nowiki>}}
** (optional if curl command was not installed) [https://help.ubidots.com/en/articles/2165289-learn-how-to-install-run-curl-on-windows-macosx-linux Learn how to install & run cURL on Windows/MacOSX/Linux | Ubidots Help Center]
** commands e.g. 
*** (1) Write output to <file> instead of stdout using {{kbd | key = <nowiki>curl -voL https://www.google.com</nowiki>}} 
*** (2) Write output to stdout using {{kbd | key = <nowiki>curl -vL https://www.google.com</nowiki>}} or {{kbd | key = <nowiki>curl -voL /dev/null https://www.google.com</nowiki>}}
*** (3) Write output to <file> with the remote file name using {{kbd | key = <nowiki>curl -vOL https://www.google.com/index.html</nowiki>}}
** If failed. It will show the message: "failed: Connection refused"

* Linux [https://www.gnu.org/software/wget/ wget] software e.g. {{kbd | key = <nowiki>wget https://www.google.com</nowiki>}}

* use the third-party website monitoring the services: [[Web Ping]] 

If the service is not the web server, use telnet instead
# (optional) [https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/cc771275(v=ws.10) Install Telnet Client | Microsoft Docs] on {{Win}}. [https://medium.com/@blackSource/bring-telnet-back-on-macos-high-sierra-11de98de1544 Bring telnet back on macOS high Sierra – Ayuth Mangmesap (blackSource) – Medium] on {{Mac}}
# {{kbd | key = telnet 127.0.0.1 <PORT>}} If failed to connect the web service. It will show the message: "telnet: Unable to connect to remote host: Connection refused"

Using alternative web services if the Python or Node.js was installed

* (for python 3.x) {{kbd | key=<nowiki>python -m http.server [port]</nowiki>}} (default port: 8000)<ref>[https://docs.python.org/3.8/library/http.server.html?highlight=http%20server#module-http.server http.server — HTTP servers — Python 3.8.1 documentation]</ref>
* (for Node.js) {{kbd | key=<nowiki>npx http-server [-p port]</nowiki>}} (default port: 8080)<ref>[https://github.com/http-party/http-server http-server: a simple static HTTP server]</ref>