How would I create a Flask WebApp which inputs keywords and outputs data from a python script which is already written?

Question

I am trying to make a WebApp with Flask which gets an input from a user which are keywords and uses that input to scrape the keywords off another website. I have written the Python script to do this using Selenium. Currently the script runs perfectly fine on my computer and outputs printed strings. It takes ~5 seconds to run (as it opens a Firefox browser).

However, I want to take this a step further by creating a website which allows users to type in the keywords, returning them the outputted strings.

So far I have tried implementing Flask on pythonanywhere.com but am having trouble connecting my script to the WebApp.

What I have so far is the following code (mostly found online and from tutorials):

from flask import Flask
from flask import render_template, abort, jsonify, request,redirect, json
from script_to_run import main
app = Flask(__name__)
app.debug = True

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/learning', methods=['POST'])
def learning():
    data = json.loads(request.data)
    # data == {"userInput": "whatever text you entered"}
    response = main(data)
    return jsonify(response)

if __name__ == '__main__':
    app.run()

This is my main app where script_to_run is the python script i want to import to run.

e.g. it may be the following

def main():
    import selenium
    #some selenium web scraping code here
    return 'successfully returned data'

And finally I have my html code:

<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
<script src="../static/script.js"></script>

</script>
</head>

<body>
    <h1>Calculation</h1>
    <h1>Test Page</h1>
    <input id="user-input" placeholder="Type keywords here; separate them with a space. e.g. lithium gold trading halt"></input>
    <p id="results">Results will go here<p>
    <button id="submit">Submit</button>
    <script>
    $(document).ready(function(){
    $("#submit").click(function(event){
        var uInput = $("#user-input").val();
        $.ajax({
              type: "POST",
              url: '/learning',
              data: JSON.stringify({userInput: uInput}),
              contentType: 'application/json',
              success: function(response){
                   $("#results").text(response.results);
                },
          });
    });
});
    </script>

</body>
</html>

I have two main questions: 1. Is what I am trying to do possible given that my script takes about 5 seconds to run and requires Firefox 2. How would I go about fixing my current code (I am currently unable to import main from script_to_run so can't even test what I've got properly)

Please note that I am a total beginner. I am okay at python (roughly 9 months learning the basics) and have almost no knowledge of web development (but can intuitively figure out basic html). Thanks!

kemis · Answer 1 · 2017-11-10T15:58:43.797

There are two ways to do this:

1) You can import the function from the other file using import and run it as a normal python function.

2) You can run python script using subprocess.

One more thing I would add is: If your script(function) takes to long too execute it will freeze your website and it will become unresponsive so you can run the script(function) in a thread and check every few seconds if the thread has finished and then display the output.

How would I create a Flask WebApp which inputs keywords and outputs data from a python script which is already written?

1 Answers1