function flash() not working with redirect()

Here’s the example:

from flask import Flask, flash, get_flashed_messages, redirect, url_for

app = Flask(__name__)
app.secret_key = 'some_secret'

@app.route('/')
def index():
    app.logger.debug(get_flashed_messages())
    return 'Hello world'

@app.route('/generate/success')
def page_success():
    flash('This message will be visible!')
    return str(get_flashed_messages())

@app.route('/generate/fail',)
def page_fail():
    flash('This message will be lost!')
    return redirect(url_for('index'))

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

As you can see flash() fails when using redirect. Tried with SERVER_NAME both set and unset. Using Flask==0.10.1.

Please resolve the issue ASAP since it’s a top blocker in my project.

[robin92]

Okay, I got it. The issue was caused by setting APPLICATION_ROOT which is discouraged in the Wiki so the fault was undoubtedly on my side. Sorry for bothering you. I’m gonna close this issue now.

[karissame]

I am having the same issue and I don’t have an APPLICATION_ROOT in my project. After flashing a message, if I return redirect('/ ') the message doesn’t appear on the redirected page but if I comment out the redirect and use return render_template("index.html") the message does display.

Setting cache timeout to 0 “fixes” this but this site relies on caching for performance reasons so if there is some way to get message flashing to work on redirect and WITH caching enabled, please let me know. Thanks!!