I'm currently in the process of making a program to upload and read csv files. I'm throwing a key error when submitting a file to be uploaded and can't really seem to figure out why and was hoping for some help. It uploaded and saved the file before I tried adding the read file functionality but after that, it started having issues. The error is saying that 'filename' is a key error even though it seemed to work fine before I tried reading the file. Help or leading me down the right path would be greatly appreciated. Thanks so much!
Views.py
from flask import render_template, request, redirect
from app import app
import os
import csv
@app.route('/', methods=["GET", "POST"])
def index():
data = []
if request.method == 'POST':
if request.files:
uploaded_file = request.files['filename'] # This line uses the same variable and worked fine
uploaded_file.save(os.path.join(app.config['FILE_UPLOADS'], uploaded_file.filename))
f = request.form['filename'] # This is the line throwing the error
with open(f) as file:
csv_file = csv.reader(file)
for row in csv_file:
data.append(row)
return redirect(request.url)
return render_template('index.html', data=data)
@app.route('/help')
def help():
return render_template('help.html')
app.config['FILE_UPLOADS'] = "C:\\Users\\Zachary\\Documents\\VSCode_Projects\\monday_webapp\\app\\static\\file\\uploads"
Index.html
{% extends "base.html" %}
{% block title %}Home{% endblock %}
{% block body %}
<div class="jumbotron">
<h1 style='text-align: center'>Zach's Web Application</h1>
</div>
<div>
<p class="lead">Upload a csv file to view its data.</p>
<form method="POST" enctype="multipart/form-data" action="/">
<input type="file" id="myFile" name="filename" accept=".csv">
<input type="submit">
</form>
</div>
<div>
{{ data }}
</div>
<div>
{% endblock %}
In flask request.form["input_name"] is used to get the input data, but not for input type=files which are accesible through request.files["input_name"], always using enctype=multipart/form-data in the form. You can get more info in the oficial documentation:
https://flask.palletsprojects.com/en/1.1.x/patterns/fileuploads/
On the other hand, request.files['filename'] is a FileStorage type, the function open(f) expects str, bytes or os.PathLike object, not FileStorage.
The following code should works:
from flask import render_template, request, redirect
from app import app
import os
import csv
@app.route('/', methods=["GET", "POST"])
def index():
data = []
if request.method == 'POST':
if request.files:
uploaded_file = request.files['filename'] # This line uses the same variable and worked fine
filepath = os.path.join(app.config['FILE_UPLOADS'], uploaded_file.filename)
uploaded_file.save(filepath)
with open(filepath) as file:
csv_file = csv.reader(file)
for row in csv_file:
data.append(row)
return redirect(request.url)
return render_template('index.html', data=data)
@app.route('/help')
def help():
return render_template('help.html')
app.config['FILE_UPLOADS'] = "C:\\Users\\Zachary\\Documents\\VSCode_Projects\\monday_webapp\\app\\static\\file\\uploads"