# Flask-user and dash?

**URL:** <https://community.plotly.com/t/flask-user-and-dash/12225>\
**Category:** Dash Python\
**Created:** [July 30, 2018, 7:56pm UTC](https://community.plotly.com/t/flask-user-and-dash/12225 "2018-07-30T19:56:35Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Wonko](https://avatars.discourse-cdn.com/v4/letter/w/8dc957/32.png) [@Wonko](https://community.plotly.com/u/Wonko)\
**Post date:** [July 30, 2018, 7:56pm UTC](https://community.plotly.com/t/flask-user-and-dash/12225/1 "2018-07-30T19:56:35Z")

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Hi,

I’m building a flask-app that really needs different user access-levels assigned to roles. This works very well with flask-user [https://flask-user.readthedocs.io/en/latest/](https://flask-user.readthedocs.io/en/latest/)

Only trouble is dash integration. As I can’t use decorators in dash as with flask-user there seem to be only three options:

- use of iframes making the role model for users useless,
- using a different library to render graphs - something I’d really like to avoid

Any ideas? And password behind password with using [https://dash.plot.ly/authentication](https://dash.plot.ly/authentication) doesn’t seem like a great idea.

Best regards,  
Wonko.

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**Author:** ![radekwlsk](https://sea2.discourse-cdn.com/flex024/user_avatar/community.plotly.com/radekwlsk/32/1385_2.png) [@radekwlsk](https://community.plotly.com/u/radekwlsk)\
**Post date:** [July 31, 2018, 7:54am UTC](https://community.plotly.com/t/flask-user-and-dash/12225/2 "2018-07-31T07:54:04Z")

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My multi-page callback, that based on `location` picks right layout and places it in `children` of `html.Div(id='page')` first checks if user is authenticated, if not, it returns login layout by default.

What I am doing is keep a `dict` of something like:

```python
pages_dict = {
    'index': {'url'='/', 'layout'=pages.index.layout},
    'view1': {'url'='/view1', 'layout'=pages.view_one.layout}
}

```

and match `pathname` of `location` to `url`, if it matches pick `layout`. You could also set URL’s as dictionary keys as I am not doing it for different reasons.

The callback is then:

```python
@app.callback(
    Output('page', 'children'),
    [Input('location', 'pathname')])
def display_content(pathname: str):
    if pathname is None:
        return html.Div()
    if current_user.is_authenticated:
        matched = [c for c in pages.keys()
                   if re.fullmatch(pages[c]['url'], pathname)]
        if matched:
            page_content = pages[matched[0]]['layout']
        else:
            page_content = [
                html.H1("Not found"),
                html.P("Requested URL '{}' was not found".format(pathname))
            ]
        content = html.Div(page_content)
    else:
        content = pages['login']['layout']
    return content

```

You can check if user is authenticated and has required role for selected url. Allowed roles could be kept in the dict as a list.

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<div class="post-metadata">

**Author:** ![Wonko](https://avatars.discourse-cdn.com/v4/letter/w/8dc957/32.png) [@Wonko](https://community.plotly.com/u/Wonko)\
**Post date:** [July 31, 2018, 10:59am UTC](https://community.plotly.com/t/flask-user-and-dash/12225/3 "2018-07-31T10:59:13Z")

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Thanks a lot for this. I will try… looks very interesting!