Simple Web App with Flask and Heroku - Python GUI for Beginners

In this tutorial, I will show you how to create a Web Application with Flask!
This video the also the first episode of The Battle of the App Frameworks, where 🤩🤩 YOU GET TO CHOOSE THE WINNER! 🤩🤩
Today we will create a simple "Hello World" Application with Flask, which includes:
* an HTML template containing the structure of a web page
* a CSS stylesheet containing design instructions
* a Python backend that communicates with a web server
And we will also 🚀DEPLOY🚀 this application for free with Heroku! 😁
This tutorial covers all the basics of Flask, from start to finish! (excluding Javascript interactions, which we will leave for later 😜)
⏰ TIME STAMPS ⏰
00:00 - Battle of the App Frameworks
00:25 - Flask Overview
01:17 - Flask Directory Structure
01:52 - HTML Structure
06:52 - Python Backend
09:31 - Warning: this is a development server ⛳
09:42 - Message Flashing
11:04 - A secret key is required
13:38 - CSS Styling
18:05 - CSS doesn't update - Clear Cache!
20:14 - Procfile and Requirements
22:42 - Deploy Flask App with Heroku
24:43 - Thanks for watching! :)
*********************************
🐍 IMPORTANT NOTES/LINKS 🐍
Install Flask 🌶
* Anaconda: conda install -c anaconda flask
* PyPI: pip install flask
Install Green Unicorn 🦄
$ pip install gunicorn
Change Production Server to Development Server: ⛳
$ export FLASK_APP=sayHello
$ export FLASK_ENV=development
$ flask run
Complete project on Github:
github.com/MariyaSha/greeting...
Link to logo from my Kivy App:
github.com/MariyaSha/SimpleGr...
Beautiful icons are by:
www.freepik.com/
www.flaticon.com/

[@robinferizi9073]

Note: html and css are not programming languages they’re mark up languages, as there is nothing in html or css that makes them Turing complete

[@PythonSimplified]

Hi Robin 😊 Don't worry, I'm definitley aware of it! After all, "markup" is the "M" of HTML! 😃 It's just not a technicality I wanted to focus on at this point in time, especially as part of a "quick overview". If I use the term "markup language" to explain a different term - I also need to explain what it means and how it differs from a "programming language". If I were to film a video about HTML or markup languages in general - I would have probably used the technical definitions instead of an abstraction. But here's a caviat - the term "markup language" is not very well defined and I can make the argument that it overlaps with the definition of "programming language". There's an ongoing debate on this, you can actually find many different opinions on Stack Overflow and each of them has a valid logic behind it. In my opinion, markup is a subset of programming as even web pages are programs in one way or another. Even static pages without any JS interactions are encoded by a computer, so it does seem to fit the definition... but that's just my opinion 😉 Anyhow, I don't see a reason to dig so deep... 😅 just refer to "markup" as an abstraction of "programming" hahahah

[@robinferizi9073]

@@PythonSimplified yeah good point, nice vid too

[@PythonSimplified]

@@robinferizi9073 thank you so much! 😃

[@shoshanamofaz3012]

You may already know this but html and css make web pages look pretty while JavaScript is the engine that makes them work.

[@robinferizi9073]

@@shoshanamofaz3012 yeah I know what they do, and that’s the reason they are known as markup languages

[@darioalb00]

Wonderful!!! I am an old developer (61 years old) trying to learn the current technologies. Already tired of volunteer tutorials that know little about teaching, I come across this one, which in just 25 minutes, conveys all the basics I need to learn. I am amazed!!! Congratulations!!!

[@PythonSimplified]

Thank you so much for the awesome comment, Darío!! I have another Flask tutorial (but twice as long unfortunately 😅 haha) and it shows you how to combine a SQLite database with your app, creating a Groceries List application: ⭐ Flask SQLite Web Application Step by Step Tutorial - HTML, Jinja, CSS, JavaScript, Python: kzbin.info/www/bejne/rGSmhIShha-nd8U It's a bit more advanced than this tutorial, but it gives you some additional tools to use on your exciting new journey :))) If you're not yet familiar with SQLite or databases in general, I have some really nice tutorials that you may find useful: ⭐ SQLite Basics: kzbin.info/www/bejne/hZnNXnandrGlrc0 ❗you'll need to add connection.commit() after each data insertion command, I've accidentally skipped it in the tutorial above 😅 then you can practice your SQLite skills and learn how you can generate databases by automatically copying them from the web (what we call Web Scraping): ⭐ Web Scrape Databases with SQLite and Mechanical Soup: kzbin.info/www/bejne/g5yqgqCQpLKoiK8 This one includes the connection.commit() command I've mentioned above 😉 Best of luck and I hope it helps! :))

[@darioalb00]

@@PythonSimplified What a frustrating!!! Much of my illusion was to see my Flask app run in the cloud. I was waiting for the weekend to have the necessary time to carry it out, and I find that Heroku is no longer free !!! Do you know any good alternative ???

[@Andrew-Escudero]

You are great! Love the clarity, simplicity, and positivity in your videos. Look forward to learning more from you!

[@developerx962]

I am so happy because you are just given us the best statement "and since we have saved this file inside the appropriate template folder, flask will be able to find it with no issues"

[@g.rioscairo]

I simply loved this tutorial. First time using Flask and Heroku! And it all worked so smoothly, nice :)

[@Soulo_Sreeni]

The way of explanation is phenomenal ! I feel great that KZbin recommended it to me today 🤩

[@PythonSimplified]

Yeey! I'm so happy you liked it! 😀 Welcome aboard! 😁

[@spadezap9728]

Thanks so much! I have been looking everywhere on how to do this and this is the only video that explained it well!

[@DevStephenW]

Just found your videos. Such a perfect tutorial. The right speed, the right amount of explanation and detail. Great stuff.

[@janusztarnowski115]

simple application enter your details kzbin.info/www/bejne/eojRZmB7n52FY68

[@thebarryman]

Best tutorial for Flask I've seen so far, thank you!

[@ralphanthony5198]

Great video, amiga! Awesome work! I definitely love all your videos!!!

[@markus4394]

Thank you for a great tutorial. Got me to transition from making simple console apps to a real webapp!

[@BogdanAnghelina]

I'm now starting to learn Python through the Mimo mobile app. After a few chapters, I started practicing and looking for more complex projects. Your video is very explanatory and I congratulate you on that! Although I have a pretty solid background in HTML, CSS, and WordPress (PHP), I'm just now starting to understand Python and I think it's awesome what you can do with it.

[@rnseby]

Thanks for the great walkthrough. Quick and straightforward.

[@darcydonelle2340]

Great video! Deployed my version of the app, and it works wonderfully, as expected. Thank you!

[@PythonSimplified]

Yeeey!! Super happy to hear!! Thank you so much 😃

[@MichaelSwartout]

I swear this is the first time I have every seen you on a windows pc. You are such a wonderful teacher. Who likes to play some Steam games and not just code. Oh ya!

[@rrivillox]

Flask is my first framework love. It's very easy and functional. Thanks my dear teacher and lovey friend. Your videos are a fresh air on Python's tutorial. :8)

[@123arskas]

Love your energy !!! Thanks for the tutorial

[@maxwellochieng4924]

You are the BEST, I found your video at a point i was learning how to deploy my ML models in Heroku

[@fersaol]

Thanks to you I have been able to deploy a working web app, you deserves all the best in the world. Thanks a lot!!!!!

[@S0190S]

Way simpler to use Heroku than AWS. Thank you for this video! I learned Flask in my bootcamp and have been needing a simpler deployment method. Thanks again!

[@mauno91]

You can force a cache refresh on a single page: Ctrl + F5 for Windows. Shift + Reload for Safari.

[@happyjohn1656]

Wow this is amazing, so awesome to know! Thanks Mauno! 🤗 9:22 PM 2/20/2022

[@godkaboom]

Ctrl+Shift+R is what you'll need to refresh without using cache

[@TheSuperRunner]

Great tutorial! I'm trying to write a web app (with basically no web experience) for a new project of mine and this made things a lot more clear.

[@eminedogan3125]

Thank you so much for this great video. Amazing clear explanation.. I am really happy I found your channel.

[@mixschnack]

Mariya Shanti doesn't babble on forever, but says, bang, bang, do this and that and everything works. And that's how it is. Here and there, some questions arise, which she partly answers - to my full satisfaction - and partly does not. For example, she doesn't explain how she manages to get the font file loaded and displayed on every system. On her system it works without additional effort, because the font ("Shanti") is installed on her system. On other systems the font would first have to be loaded from a website or an appropriate stored font file. All in all, this video gives a good overview of the steps necessary to develop and deploy a web app and introduces some "best practices" that are common among experienced programmers. A great video. More of it please!

[@niklase5901]

Great! Just the intro i needed for this! Thanks!

[@kayodeadechinan5928]

I really like your way of teaching! Great videos!

[@trtlphnx]

I Love Your Lessons; Very Eclectic and Cogent ~ You Are Vastly Appreciated ~!

[@PythonSimplified]

Thank you so much for the lovely feedback, trtlphnx! 😁

[@renderartist]

Incredibly helpful and fun tutorial, thank you! Building some experiments with flask that I made with ChatGPT and seeing how easy it is to take it online in a nice packaged way is great. I like that there are options for easy to deploy SQL databases in Heroku. 👍🏼

[@estebanglsa]

I love these videos! You really do a great job explaining. The sad part is: Heroku no longer offer free deployment 😥

[@vigneshpadmanabhan]

Thanks a lot! Such an amazing video. I have always wanted to deploy the solutions I create on the web, but never took the step, thanks to the youtube algorithm, found this video by chance and I like your teaching approach. It's simple to follow and easy to execute. Would love to see a sequel to this video.. would it be possible for us to have a MySQL or SQLite or PostgreSQL anything you would prefer, that can store the names we type? I am interested to learn more about this. A little bit about myself, I'm a data science guy and I never got a chance to do anything beyond proof of concept at work and personally was never exposed to a platform that can host an app on the web free. So this is my start. Thanks again!

[@simonmenlah1817]

Hey! I just fell in love with you and your method of teaching and can't stop learning via your channel...

[@achinthasandaruwan9435]

Simplifying overload! Btw, I love KZbin algorithm ❤️

[@bharathkarkera3223]

explanation in best possible way.. thank you so much!!

[@evertonsston]

Thank you so much for this explanation!!

[@netbin]

Exploring python with Cécile’s videos becoming even more fun

[@mindfreaksaad]

This is a fantastic guide. Thanks!

[@HakermodOfficiel]

Just what I needed. Thank you

[@watermanli]

It's really beautiful, Amazing.......ly! You opened the door, in such a nice and clear way...

[@erickanyiri3463]

How am i just finding your channel now 😊 Great stuff

[@ashutoshdevgotra]

best ever tutorial, I am from india...keep making such easy and learning full projects

[@user-wf1rp2hp5u]

항상 잘 보고 있어요!

[@myke6972]

don't know anything about flask yet, but after I watched this video, I understand all of the parts discussed in the video, thanks alot!

[@BigPoppaJNutZ]

Another great tutorial! Thanks!

[@bicycleninja1685]

You're very talented and knowledgeable! Thanks for taking us through the steps.

[@PythonSimplified]

Thank you so much Bicycle Ninja! 😀 I have an additional Flask tutorial if you'd like to combine your app with an SQLite database: kzbin.info/www/bejne/rGSmhIShha-nd8U It's a bit longer than this one, but it's also a much more useful application 😉

[@bicycleninja1685]

@@PythonSimplified Will check it out! I also loved your Python graphics tutorial with the procedurally generated trees and landscape. Absolute genius! Helps grasp the concept and take it to another level.

[@johnwindsor5426]

So nice talk. it is a gread video tutor. I like it so much! Last about heroku part, it is super!😊👍👍👍

[@NagasakiNightmare]

I feel like no one is doing what you’re doing. I’m glad to have found this, because I can code in Python well enough, but I have never done anything front end outside of ncurses. (Old man, new tricks)😂 Thank you so much!

[@omarpalacios9734]

Awesome video! Thank you so much. Спасибо :)

[@Gorlung]

your videos broaden my knowledge and inflame my libido

[@gaudino110]

Great tutorial, simple but quite complete. Your speech is lovely, not too fast and perfectly understandable even for a non native English speaker like me. I'm in love with you, not gonna lie.

[@thomasschnitt2840]

Thanks for the video! A little remark: UTF-8 is not necessarily 8-bit. It is a variable-length character encoding standard using one to four one-byte (8-bit) code units.

[@She_cooks2023]

Great Job!!! Loved it totally

[@narbigogul5723]

Great video, thanks for sharing!

[@ianpropst-campbell6028]

Thank you for this great video!

[@meganwancura4013]

This was so helpful!!!! Thank you!!!!

[@Tobs_]

awesome, this is something I have been keen to learn from you 👍

[@PythonSimplified]

Happy to hear Tobs! 😁

[@lenapham9377]

Great teacher, wish you all the best!

[@bekiyerom62]

thanks lovely you do it in the most simplest way

[@adedoyinayobami2820]

I have a problem activating my virtual env with my windows cmd.great content enjoy your tutorial up to the virtual env moment

[@DevPasjaByDanielSmigiela]

You're amazing! I love you so much :D

[@MrThekid2009]

Liked, Subscribed & hooked for life! Kudos!

[@PythonSimplified]

Yeeey!! Super happy to hear! Welcome aboard!! 😃😃😃

[@SuperlativeCG]

Great tutorial. Very helpful.

[@gabrielfernandez9660]

I love your videotutorials!!

[@nicosaavedra82]

Thanks!! i did it!! so happy!

[@alexnefayne4266]

This is a great tutorial.. Thankyou.

[@nathanaelmehari1909]

Thank you very much i enjoyed the course because you try to make it fun as possible

[@freezoulou]

Well explain as always I repeat again and again thank you very much you help me a lot :)

[@PythonSimplified]

Thank you so much dexteuse freeman! I'm so happy to hear that! 😀😀😀

[@cesarac666]

oH my God! The only one that Run fine!! Greate Job Mariya....Thx

[@---------------__]

I really enjoyed your tutorial :)

[@NOURTCS]

Great perfect 🤩 you do beautiful coding & clean Thanks

[@PythonSimplified]

Thank you Noureddin! 😁

[@AlexanderMaynor-tt3fx]

You are a angelic human being and so smart! Thank you for making such amazing content and being a light for the world!

[@PythonSimplified]

Wow, Alexander! Thank you so much for the incredible comment!! 😀😀😀 It's a great honour to have lovely folks such as yourself supporting me on this magical journey! 😊

[@theronkasita4196]

Well explained Thank you all the way from Africa Namibia

[@yoyochris924]

Great explanation. Thanks!

[@lirostin]

Thank you for your video! I made it )

[@mightyaripage]

Love the manbearpig reference

[@mbundesmond3696]

Wow great explanation, thumbs up ☺️❤️

[@falagerifamily]

So great!! Thanks🎉🎉

[@DaveFanch1022]

Awesome explanation! I'm working on a web trading app and Heroku was a great option to deploy!

[@PythonSimplified]

Thank you so much Dave! Super glad I could help! 🙂 I'm actually going to share an even better solution than Heroku in the next few days - there's a new way to deploy your Flask/Django apps directly from the IDE! It's not out publicly yet, but I got special access and I can't wait to share it with everybody! 😃😃😃

[@SadaraxTutorials]

@@PythonSimplified Hey, love the video! Do you know when you'll be releasing the Django directly from IDE video? I'd love to see it!

[@kwamenadadson]

Thanks your video saved my life today

[@dacianfd8418]

Nice!

[@bazazoo2827]

Hello Mariya, great to see ya 8D I'll be waiting for the update on the DearPy GUI app, docs are not up for mass adoption yet

[@Blooddarkstar]

This was brilliant!

[@hichamtutorials7170]

Hi there I have a question I created a python script that extract data from web using beautifulsoup is there a way I can run it from a html web page

[@lexiepan4257]

Hi Maria, I am quite new to coding, followed all the steps you showed, but I got a different requirement.txt which contains a lot of packages and a lot of @ file .../.../.../. So I don't know the reason for this and also don't know if I should replace all the @ file .../.../.../, like the markup safe one you did in the video.

[@x-jbbj-x8107]

Thanks for the help !!!

[@udbhav3760]

I learned something new today thanks for the video ✌️

[@PythonSimplified]

Thank you Udbhav! :DDD

[@taylortoast2]

@PythonSimplified which part of this app utilizes JavaScript? Thank you for your content.

[@roshanikumbharkar6266]

thank you so much dude you're a god

[@giovannicanedoli7669]

This was so interesting, really a nice video!

[@PythonSimplified]

Thank you! 😊

[@toulasantha]

👏👏👏 charisma factor 100%

[@incaroads001]

I was just about to have my nieces watch this video. Then you greeted s-man.

[@Ozimbat]

Amazing video as usual!

[@PythonSimplified]

Thank you so much Ozimba! 😁😁😁

[@pulsarasandeepa7948]

Your content is great and simply explained💕

[@PythonSimplified]

Thank you so much! I'm super happy to help! 😃 BTW, have you seen my recent Flask tutorial where we combine an SQLite database in our app? you can check it out here: kzbin.info/www/bejne/rGSmhIShha-nd8U It's a grocery list application and it's a really fun project, especially if you're into web development 😉 I really hope you like it!

[@pulsarasandeepa7948]

Yeah definitely, I am learning to build a web app using sqlite db by watching your tutorials. Your tutorials are very interesting🎊️🔥

[@paulthomas1052]

Great work !!

[@biniyammengiste7413]

waw, very nice. Thank you!!

[@blaiseyonga9686]

I enjoy the way you explain something😄😄😄😄

[@roboxito1]

Nice to known Flash() function

[@learnincredibledesign]

Love the way of teaching

[@RocketLR]

Is there someway to get a liveserver to refresh html and css while developing? I am SOOOO tired of refreshing the browser every time i make changes to the templates.

[@Grab-Deals]

Hi I love the video thank you so much for your amazing work! I was wondering how I get HTML or CSS program language or whatever is needed on sublime, so I can make sure I'm doing this right! 😇

[@MyTubeAIFlaskApp]

This video inspired me to learn Flask Because of you, I am here.Thank You very much.