Flask Error 404

[poonamhr]

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Hello! I'm working on cs50 project.When I try to open the link provided after executing flask run it shows the webpage is not found.HTTP ERROR 404.Although my code is correct.This error is appearing on my other projects as well, the ones that I had already submitted many days before.I tried reinstalling flask and it working but now again on the problem.How can I solve this issue?Please HELP!
Thank You!

[poonamhr]

Hello! I'm still having the same issue.The flask link sometimes loads and sometimes not. I tried every way but still don't understand why this happens. The link my flask provides me in the terminal is: https://silver-xylophone-695vxp9p9gv2567w-5000.app.github.dev/login Thank You!

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On Fri, 5 Apr 2024, 21:31 Giovanni Vicentin, ***@***.***> wrote: Hello poonamhr, It sounds like you're encountering a persistent HTTP 404 error when trying to access your Flask applications, even on projects that previously worked fine. This typically indicates that the URL you're trying to reach does not correspond to a valid route in your Flask application. Here are a few steps you can take to troubleshoot and potentially solve this issue: 1. *Check Your Routes*: Ensure that the URL you are trying to access matches a route defined in your Flask application. Pay close attention to any typos or mismatches in the route path. 2. *Debug Mode*: Run your Flask application in debug mode by setting app.debug = True or running Flask with the environment variable FLASK_ENV=development. This can provide more detailed error messages that might point to the source of the issue. 3. *Environment Variables*: If you've reinstalled Flask or made changes to your environment, ensure that all necessary environment variables are correctly set. For CS50 projects, make sure you're following the setup instructions exactly as provided in the course materials. 4. *Virtual Environment*: Consider using a Python virtual environment if you aren't already. This can help isolate your project dependencies and avoid conflicts. You can create one with python -m venv env and activate it with source env/bin/activate on Unix/macOS or env\Scripts\activate on Windows. 5. *Review Flask Application Structure*: Ensure your Flask application's structure is set up correctly, including the __init__.py file in your project folders, as Flask uses these to recognize package boundaries. 6. *Logs and Error Messages*: Look at the terminal or command prompt from which you're running your Flask application for any error messages or warnings that could give clues about what's wrong. 7. *Revisit Working Commit*: If your projects are version-controlled with Git, consider reverting to a commit where you know the application was working. This can help determine whether recent changes have introduced the issue. 8. *CS50 IDE Specifics*: If you're using CS50 IDE, ensure that you're accessing your application through the IDE's web preview feature. URLs typically have a specific format in CS50 IDE, often including your workspace ID. 9. *Flask Extensions and Dependencies*: If your Flask application relies on extensions or external libraries, ensure they are installed and up to date. Sometimes, issues can arise from incompatibilities or updates in these dependencies. 10. *Community and Documentation*: Don't hesitate to consult the Flask documentation or search for similar issues in Flask communities or forums. Sometimes, the solution lies in a small detail easily overlooked. If after trying these steps the issue persists, consider providing more detailed information about your Flask application's structure, the specific routes you're trying to access, and any error messages you're seeing in the terminal. This additional context can be crucial in diagnosing more complex issues. Best of luck with your CS50 project, and I hope you find a resolution soon! Best regards. — Reply to this email directly, view it on GitHub <#116947 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BDNKOEGFIFCM37XLLN4JV2DY33UZHAVCNFSM6AAAAABFZSE6BSVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4TAMRUHE3TG> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[Moinuddin-lgtm]

Response #2

[hzhuo8880]

Hi! I am having the same issue. flask run hasn't been working for me since yesterday. I also found out that http-server has the same exact issue. They both just return http error 404.

Please let me know if you found any solutions. Thank you!!

[poonamhr]

Hello! I apologise if I disturbed. But I want to share something. Firstly I had an error 404 with flask, now when I opened my file it had code included which didn't write. I have written my code in English and those "included" words were in Greek. Is it hacked? it's CS50 codespace. Thank You!

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On Fri, 5 Apr 2024, 21:31 Giovanni Vicentin, ***@***.***> wrote: Hello poonamhr, It sounds like you're encountering a persistent HTTP 404 error when trying to access your Flask applications, even on projects that previously worked fine. This typically indicates that the URL you're trying to reach does not correspond to a valid route in your Flask application. Here are a few steps you can take to troubleshoot and potentially solve this issue: 1. *Check Your Routes*: Ensure that the URL you are trying to access matches a route defined in your Flask application. Pay close attention to any typos or mismatches in the route path. 2. *Debug Mode*: Run your Flask application in debug mode by setting app.debug = True or running Flask with the environment variable FLASK_ENV=development. This can provide more detailed error messages that might point to the source of the issue. 3. *Environment Variables*: If you've reinstalled Flask or made changes to your environment, ensure that all necessary environment variables are correctly set. For CS50 projects, make sure you're following the setup instructions exactly as provided in the course materials. 4. *Virtual Environment*: Consider using a Python virtual environment if you aren't already. This can help isolate your project dependencies and avoid conflicts. You can create one with python -m venv env and activate it with source env/bin/activate on Unix/macOS or env\Scripts\activate on Windows. 5. *Review Flask Application Structure*: Ensure your Flask application's structure is set up correctly, including the __init__.py file in your project folders, as Flask uses these to recognize package boundaries. 6. *Logs and Error Messages*: Look at the terminal or command prompt from which you're running your Flask application for any error messages or warnings that could give clues about what's wrong. 7. *Revisit Working Commit*: If your projects are version-controlled with Git, consider reverting to a commit where you know the application was working. This can help determine whether recent changes have introduced the issue. 8. *CS50 IDE Specifics*: If you're using CS50 IDE, ensure that you're accessing your application through the IDE's web preview feature. URLs typically have a specific format in CS50 IDE, often including your workspace ID. 9. *Flask Extensions and Dependencies*: If your Flask application relies on extensions or external libraries, ensure they are installed and up to date. Sometimes, issues can arise from incompatibilities or updates in these dependencies. 10. *Community and Documentation*: Don't hesitate to consult the Flask documentation or search for similar issues in Flask communities or forums. Sometimes, the solution lies in a small detail easily overlooked. If after trying these steps the issue persists, consider providing more detailed information about your Flask application's structure, the specific routes you're trying to access, and any error messages you're seeing in the terminal. This additional context can be crucial in diagnosing more complex issues. Best of luck with your CS50 project, and I hope you find a resolution soon! Best regards. — Reply to this email directly, view it on GitHub <#116947 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BDNKOEGFIFCM37XLLN4JV2DY33UZHAVCNFSM6AAAAABFZSE6BSVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4TAMRUHE3TG> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[Marakasss]

Hi!
The same problem occurred to me. Open the PORTS window in the terminal and look for the port with the link provided by FLASK. In my case, it's port 5000. However, it was missing from the list of ports. When I manually added it, everything started working.