Skip to main content

How can I display a message or loading animation while flask.send_from_directory is processing?

I have a simple web application that calls the Spotify API, and, among other things, allows a user to download their "Liked Songs". The 'download' view writes a csv file of the 'Liked Songs' to a tmp directory and then downloads that file using flask.send_from_directory.

@bp.route('/download', methods=['GET'])
@login_required
def download():
    ...
# Edited with more details below

    return send_from_directory(
        temp_dir,
        target[0],
        as_attachment=True,
        attachment_filename=file_name
    )

It all works as intended but can take a while if a user has many thousands of Liked Songs. During that 20+ seconds I would like to give the user some feedback that the task is processing -- a message or loading animation. I have written a loading animation used elsewhere in my site, but in those cases the view ends with a redirect. I also can reveal a modal with javascript. However, a modal or animation will not automatically close when the "Open Liked Songs.csv" window pops up asking the user to "Open" or "Save", nor after one of those is selected (i.e., when the download view is completed).

Is there a way to trigger an event in the Browser Object Model using the window object for the "Open Liked Songs.csv" pop-up window? I do not know how to identify that specific window. Any other suggestions?

UPDATE: Thanks to @v25 I realize more details are needed. Here is my code again:

@bp.route('/download', methods=['GET'])
@login_required
def download(backup=False):
    ...

    if backup:  # For download of 'Liked Songs'
        playlist_id = '000library'
        file_name = 'Liked Songs.csv'
        url = get_endpoint("get-user-saved-tracks")
        query_limit = 50

    count = 0
    tracks = []

# The Spotify endpoint is limited at maximum of 50
# so I need to iterate with offsets.
# I think this is what is causing the delay.

    while not len(tracks) % query_limit:
        params["limit"] = query_limit
        params["offset"] = query_limit * count
        section = sh.get_playlist_tracks(header, url, **params)
        tracks += section["items"]
        count += 1

    if not tracks:
        flash("Something went wrong. We couldn't get your playlist.")
        return redirect(url_for('routes.profile'))

    with NamedTemporaryFile(
                        mode='w+t',
                        encoding='utf8',
                        newline='',
                        prefix=playlist_id + '.',
                        dir=temp_dir,
                        delete=False,
                                        ) as csvfile:
           ...  

          # Writes csv file to temp directory

    ...
    return send_from_directory(
        temp_dir,
        target[0],
        as_attachment=True,
        attachment_filename=file_name
    )

When I monitor this process with my browser's (FireFox) dev tools 'Network' tab, I can see that it takes a while before status code 200 is returned for my '/download' request. At that point the 'Open Liked Songs.csv' window appears. I think I need some way to trigger my javascript closeModal() when status 200 is returned (polling?). As @v25 suggests below, I am pretty sure it is the iteration of 50-track chunks at the Spotify API that is slowing this down.

Via Active questions tagged javascript - Stack Overflow https://ift.tt/2FdjaAW

Comments

Popular posts from this blog

Confusion between commands.Bot and discord.Client | Which one should I use?

Whenever you look at YouTube tutorials or code from this website there is a real variation. Some developers use client = discord.Client(intents=intents) while the others use bot = commands.Bot(command_prefix="something", intents=intents) . Now I know slightly about the difference but I get errors from different places from my code when I use either of them and its confusing. Especially since there has a few changes over the years in discord.py it is hard to find the real difference. I tried sticking to discord.Client then I found that there are more features in commands.Bot . Then I found errors when using commands.Bot . An example of this is: When I try to use commands.Bot client = commands.Bot(command_prefix=">",intents=intents) async def load(): for filename in os.listdir("./Cogs"): if filename.endswith(".py"): client.load_extension(f"Cogs.{filename[:-3]}") The above doesnt giveany response from my Cogs ...

How to show number of registered users in Laravel based on usertype?

i'm trying to display data from the database in the admin dashboard i used this: <?php use Illuminate\Support\Facades\DB; $users = DB::table('users')->count(); echo $users; ?> and i have successfully get the correct data from the database but what if i want to display a specific data for example in this user table there is "usertype" that specify if the user is normal user or admin i want to user the same code above but to display a specific usertype i tried this: <?php use Illuminate\Support\Facades\DB; $users = DB::table('users')->count()->WHERE usertype =admin; echo $users; ?> but it didn't work, what am i doing wrong? source https://stackoverflow.com/questions/68199726/how-to-show-number-of-registered-users-in-laravel-based-on-usertype

Where and how is this Laravel kernel constructor called? [closed]

Where and how is this Laravel kernel constructor called? public fucntion __construct(Application $app, $Router $roouter) { } I have read the documentation and some online tutorial but I can find any clear explanation. I am learning Laravel and I am wondering where does this kernel constructor receives its arguments from. "POSTMOTERM" CLARIFICATION: Here is more clarity.I have checked the boostrap/app.php and it is only used for boostrapping the interfaces into the container class. What is not clear to me is where and how the Kernel class is instatiated and the arguments passed to the object calling the constructor.Something similar to; obj = new kernel(arg1,arg2) or, is the framework using some magic functions somewhere? Special gratitude to those who burn their eyeballs and brain cells on this trivia before it goes into a full blown menopause alias "MARKED AS DUPLICATE". To some of the itchy-finger keyboard warriors, a.k.a The mods,because I believe in th...