app.py

"""
Project: Carzam - CS 467 Capstone
Filename: app.py
Description: The routes for this application. Utilizes Flask and sets up routes and 
             what information is passed back to the html to be rendered.
"""

# Reference: 
# https://flask.palletsprojects.com/en/1.1.x/patterns/fileuploads/


# Need this so the web app can read common directory scripts
import os
import sys
import shutil
sys.path.append('./common')

# Outside dependencies
from pathlib import Path
from flask import Flask, flash, request, redirect, url_for, render_template
from werkzeug.datastructures import FileStorage
from werkzeug.utils import secure_filename

# Dependencies we created
from common.carzam import allowed_file, parse_file

# CONSTANTS - CAN BE CHANGED
OUT_DIRECTORY = "./static/outimages/"
IN_DIRECTORY = "./static/testimages/"

# Make the directories declared as constants if they do not exist
# Path(IN_DIRECTORY).mkdir(parents=True, exist_ok=True)
# Path(OUT_DIRECTORY).mkdir(parents=True, exist_ok=True)
PATH = os.getcwd()
UPLOAD_FOLDER = os.path.join(PATH, IN_DIRECTORY[2:])

app = Flask(__name__)
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER

# Max File Size Before Upload Is Aborted
app.config['MAX_CONTENT_LENGTH'] = 16 * 1024 * 1024

# Disable Cache To Display New Image On Overwrite
app.config['SEND_FILE_MAX_AGE_DEFAULT'] = 0

# Saves the uploaded file to the upload_folder and returns a string
# representative of the path to the file
def save_file_to_upload_directory(file: FileStorage):
    filename = secure_filename(file.filename)
    file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
    return os.path.join(app.config['UPLOAD_FOLDER'], filename)

#
# Routing
#

# Home Route
@app.route("/", methods=['GET', 'POST'])
def home_page():
    if request.method == 'POST':
        
        # on new upload event, remove old images from server
        shutil.rmtree(IN_DIRECTORY)
        shutil.rmtree(OUT_DIRECTORY)
        Path(IN_DIRECTORY).mkdir(parents=True, exist_ok=True)
        Path(OUT_DIRECTORY).mkdir(parents=True, exist_ok=True)

        # check if the post request has the file part
        if 'file' not in request.files:
            flash('No file')
            return redirect(request.url)
        file = request.files['file']
        # if user does not select file, browser also
        # submit an empty part without filename
        if file.filename == '':
            flash('No selected file')
            return redirect(request.url)

        # This looks like the case when the file was uploaded and it was valid
        file_type_result = allowed_file(file.filename)
        print(f"file_type_result: {file_type_result}")
        if file and file_type_result and type(file_type_result) == type(True):
            path_to_file = save_file_to_upload_directory(file)
            # pass file to carzam.py
            results = parse_file(path_to_file)
            cropped_file_list = [(path, car, conf) for path, car, conf in results]

            return render_template('index.html', filename = cropped_file_list)
            #return str(cropped_file_list)
        else:
            return render_template('index.html', filename = file_type_result)

    # return redirect(request.url)
    return render_template('index.html')

# Route To Serve Image
# changed this route
@app.route('/<filename>')
def display_image(filename):
	return redirect(url_for('static', filename = filename), code = 307)

# run app.py on local host port 8080
if __name__ == "__main__":           
#    app.debug = True
	
    # bind to dynamic PORT if defined, otherwise default to 8080
    # host '0.0.0.0' allows external programs to access the container
    envPort = int(os.environ.get('PORT', 8080))
    app.run(host='0.0.0.0', port = envPort)
    
    # host '127.0.0.1' is not accessible to Mac OS
    # however, it may be required for other OS's
    #app.run(host='127.0.0.1',port = 8080)