python – Where does flask look for image files?-ThrowExceptions

Exception or error:

I am setting up a local server using flask. All I want to do currently is display an image using the img tag in the index.html page. But I keep getting error

GET http://localhost:5000/
ayrton_senna_movie_wallpaper_by_bashgfx-d4cm6x6.jpg 404 (NOT FOUND)  

Where does flask look for files? A Little help would be great.
My HTML code is


    <h1>Hi Lionel Messi</h1>

  <img src= "ayrton_senna_movie_wallpaper_by_bashgfx-d4cm6x6.jpg ">



My python code is :

@app.route('/index', methods=['GET', 'POST'])
def lionel(): 
    return app.send_static_file('index.html')
How to solve:

Is the image file ayrton_senna_movie_wallpaper_by_bashgfx-d4cm6x6.jpg in your static directory? If you move it to your static directory and update your HTML as such:

<img src="/static/ayrton_senna_movie_wallpaper_by_bashgfx-d4cm6x6.jpg">

It should work.

Also, it is worth noting, there is a better way to structure this.

File structure:

from flask import Flask, render_template, url_for
app = Flask(__name__)

@app.route('/index', methods=['GET', 'POST'])
def lionel(): 
    return render_template('index.html')

if __name__ == '__main__':



    <h1>Hi Lionel Messi</h1>

  <img src="{{url_for('static', filename='ayrton_senna_movie_wallpaper_by_bashgfx-d4cm6x6.jpg')}}" />



Doing it this way ensures that you are not hard-coding a URL path for your static assets.


use absolute path where the image actually exists
(e.g) ‘/home/artitra/pictures/filename.jpg’

or create static folder inside your project directory like this

| templates
   - static/
         - images/
              - yourimagename.jpg

then do this

app = Flask(__name__, static_url_path='/static')

then you can access your image like this in index.html

src ="/static/images/yourimage.jpg" 

in img tag


From the documentation:

Dynamic web applications also need static files. That’s usually where
the CSS and JavaScript files are coming from. Ideally your web server
is configured to serve them for you, but during development Flask can
do that as well. Just create a folder called static in your package or
next to your module and it will be available at /static on the

To generate URLs for static files, use the special 'static' endpoint

url_for('static', filename='style.css')

The file has to be stored on the filesystem as static/style.css.


It took me a while to figure this out too. url_for in Flask looks for endpoints that you specified in the script.

So if you have a decorator in your file like @blah.route('/folder.subfolder') then Flask will recognize the command {{ url_for('folder.subfolder') , filename = "some_image.jpg" }} . The 'folder.subfolder' argument sends it to a Flask endpoint it recognizes.

However let us say that you stored your image file, some_image.jpg, in your subfolder, BUT did not specify this subfolder as a route endpoint in your flask, your route decorator looks like @blah.routes('/folder'). You then have to ask for your image file this way:
{{ url_for('folder'), filename = 'subfolder/some_image.jpg' }}

I.E. you tell Flask to go to the endpoint it knows, “folder”,
then direct it from there by putting the subdirectory path in the filename argument.

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