The browser (or proxy) sent a request that this server could not understand.

Question

Problem :

I am trying to do the file upload & enter the data task into my MongoDB using a flask but I had below error when I filled my form & upload my image:

“Bad Request The browser (or proxy) sent a request that this server could not understand.”

 My Python Code:

@app.route('/', methods=['GET', 'POST'])
def index():
   mytarget = os.path.join(app_root, 'static/img/')
    if not os.path.isdir(mytarget):
        os.mkdir(mytarget)
    if request.method == 'POST':
        myname = request.form['u_name']
        mypassword = request.form['u_pass']
        myemail = request.form['u_email']
        file_name = ''
        for file in request.form['u_img']:
            file_name = file.filename
            mydestination = '/'.join([mytarget, file_name])
            file.save(mydestination)
        mongo.db.employee_entry.insert({'name': myname, 'password': mypassword, 'email': myemail, 'img_name': file_name})
        return render_template('index.html')
    else:
        return render_template('index.html')

 

Answer 1

Your error is resulting from the BadRequestKeyError because of access to the key that doesn't exist in your request.form.

ipdb> request.form['u_img']
*** BadRequestKeyError: 400 Bad Request: The browser (or proxy) sent a request that this server could not understand.

Uploaded files are keyed under the request.files and not the request.form dictionary. Also, you need to use the loop as the value keyed under u_img is the instance of FileStorage and not at all iterable.

Please refer below updated code that will help you in resolving all of the issues.

@app.route('/', methods=['GET', 'POST'])
def index():
    mytarget = os.path.join(app_root, 'static/img/')
    if not os.path.isdir(mytarget):
        os.makedirs(mytarget)
    if request.method == 'POST':
        ...
        file = request.files['u_img']
        file_name = file.myfilename or ''
        mydestination = '/'.join([mytarget, file_name])
        file.save(mydestination)
        ...
    return render_template('index.html')