POST handler executed instead of GET handler

[skanderturki]

I have sent the full code below. To reproduce the strange behavior:
Run both the server and the client, send a request throw the form , check that you are sending a GET request using developer tools then, on the server check that the app.post handler is being executed. Note that there ia a problem in the form, it is not executing the js script because of a missing property in the button (type="button"), so the type of the button is by default "submit" and the request that is being sent is a GET request sending the data on the URL query part. But why is the server executing the app.post handler?

Environment information

Version:

"dependencies": {
"cors": "^2.8.5",
"dotenv": "^16.5.0",
"express": "^5.1.0",
"mysql2": "^3.14.0",
"sequelize": "^6.37.7"
}

Platform:
Microsoft Windows NT 10.0.26100.0
x64

Node.js version:
v22.14.0

Any other relevant information:
Full code is here:
Description: a server app and a client app, just add a MySQL server connection details or simply remove connection to DB as it is not relevant here:
https://drive.google.com/file/d/1P-50C95h5RAMYarO-scfUHaLLPq1mmZF/view?usp=sharing

[krzysdz]

This sounds impossible and I can't reproduce it with your example. Could you add some logging to your server's app.js to check request method and URL?

// Add this before your route definitions
app.use((req, res, next) => {
  console.log(req.method, req.url, req.headers['user-agent'])
  next()
})

BTW please don't send archives (or links to archives) on GitHub - include short snippets of code or use a separate repo/gist.

[skanderturki]

Ok, you were right, something I don't get is happening at the client side, so nothing to do with express: here is the listing you asked for, it shows that the server is actually getting a POST request:
POST /api/v1/countries/name/ert/phonecode/123 Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36

And here is a video that shows the strange behavior (caused by the client ..or my misunderstanding of what the browser is doing):
https://youtu.be/bN2DTRrZm28

[krzysdz]

The User Agent is one of a browser. Your video shows that the browser performs a fetch request to URL ending with /45 that originates from countries.js:11, just before navigating to /?name=rt&phonecode=45. This later disappears after the document loads, because Preserve log is unchecked.

I'd suggest using submit event to process form submission and prevent default behaviour.

[skanderturki]

Thank a lot that was very helpful, I am closing this thread