reznov11 reznov11 - 1 year ago 148
Apache Configuration Question

Why am getting Bad Request in login page and search form, FLASK?

If i want to log into my control panel am getting 400 bad request error that says:

Bad Request

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

I have also a search form , if i want to search for something through the database, am getting the same error .

The site is working on
webserver, what really interesting is that, if a ran the application using the
python runserver
command, the error won't show any more just in Apache the error showing up .

Here is how the code looks like in my

@app.route('/login/', methods=('GET', 'POST'))


def login():

if session.get('username') or session.get('is_author') == True:

flash("Already logged in .")

return redirect(url_for('index'))

form = LoginForm()

error = None

if request.method == 'GET' and request.args.get('next'):

session['next'] = request.args.get('next')

if form.validate_on_submit():

user = User.query.filter_by(

username =


if user:

if bcrypt.hashpw(, user.password) == user.password:

session['username'] =

session['is_author'] = user.is_author

if 'next' in session:

next = session.get('next')


return redirect(next)


flash('Welcome back %s'%session['username'].upper())

return redirect(url_for('index'))


error = "Incorrect username or password ."




error = "Incorrect username or username ."

return render_template('auth/login.html', form=form)

Also the search code in

def replace_last(source_string, replace_what, replace_with):

head, sep, tail = source_string.rpartition(replace_what)

return head + replace_with + tail

@app.route('/search/<query>', methods=['GET','POST'])

def search_engine(query):

user = User.query.first()


query = request.form['autocomplete']

r = replace_last(query, ' ', '')

posts = Post.query.filter('%'+r+'%')).order_by(Post.publish_date.desc())

except TypeError:

flash('No results.')

return render_template('main/search_form.html')

context = {






return render_template('main/search_form.html', **context)

Another thing to mention is that, my site is running under HTTPS , maybe this causing some problems, i really don't know !! , in fact am using Letsencrypt, in another article I've seen the people are saying that there's a certain problem when using flask and HTTPS especially when using requests like POST or GET, but i really deleted Letsencrypt from my server restarted Apache but that didn't solved the problem , am really frustrated don't know what to do.

Another thing i forgot to add, is the App.conf in /etc/apache2/site-available , maybe it help some way to know what causing the problem :

<VirtualHost *:80>
WSGIScriptAlias / /var/www/MyApp/flaskapp.wsgi
<Directory /var/www/MyApp/siteapp/>
Order allow,deny
Allow from all
Alias /static /var/www/MyApp/siteapp/static
<Directory /var/www/MyApp/siteapp/static/>
Order allow,deny
Allow from all
ErrorLog ${APACHE_LOG_DIR}/error.log
LogLevel warn
CustomLog ${APACHE_LOG_DIR}/access.log combined
RewriteEngine on
RewriteCond %{SERVER_NAME} [OR]
RewriteCond %{SERVER_NAME}
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,QSA,R=permanent]

i did a proxy redirection, so i ran my application using the
command, then inside App.conf i added these too lines of codes :

ProxyPass /
ProxyPassReverse /

So by that, the Bad Request disappeared, the wired thing now is, always i'am getting wtform error that says:

This field is required.

means its empty, practically its not, i really typing information and handling them inside my as i mentioned above .

Eventually, please any help would be a millions appreciated .

Answer Source

I solved the problem, in case you faced this unbelievable, undebugable problem do the following:

  1. remove Apache2 with all it dependencies, so :

    sudo apt-get purge apache2 apache2-utils

  2. then follow this tutorial which is about, how to deploy your flask application on nginx webserver:

That's it, I'am really truly very happy right now :) .

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