Dash: Shows dcc.Location atributes available in dcc.Link

dcc_Location.py

import dash
import dash_core_components as dcc
import dash_html_components as html

print(dcc.__version__) # 0.6.0 or above is required

external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']

app = dash.Dash(__name__, external_stylesheets=external_stylesheets)

app.layout = html.Div([
    # represents the URL bar, doesn't render anything
    dcc.Location(id='url', refresh=False),

    dcc.Link('Navigate to "/"', href='/'),
    html.Br(),
    dcc.Link('Navigate to "/page-2"', href='/page-2'),

    # content will be rendered in this element
    html.Div(id='href'),
    html.Div(id='page-content'),
    html.Div(id='qs'),
    html.Div(id='hash')
])


@app.callback(dash.dependencies.Output('page-content', 'children'),
              [dash.dependencies.Input('url', 'pathname')])
def display_page(pathname):
    return html.Div([
        html.H3('You are on page {}'.format(pathname))
    ])


@app.callback(dash.dependencies.Output('href', 'children'),
              [dash.dependencies.Input('url', 'href')])
def display_page(href):
    return html.Div([
        html.H3('This is the href: {}'.format(href))
    ])


@app.callback(dash.dependencies.Output('qs', 'children'),
              [dash.dependencies.Input('url', 'search')])
def display_page(qs):
    # Surprinsingly, this callback is called with search = None
    # before to be called again with the actual url :S
    print ('This is the query string: {}'.format(qs))
    # This callback should not be called when the query string of the url isnt affected!!!
    return html.Div([
        html.H3('This is the query string: {}'.format(qs))
    ])

# Same here, this callback gets triggered every time with first hash=None and
#  then hash = actual value and the callback gets called everytime the path
#  changes, also when the *hash* part hasn't been modified.
@app.callback(dash.dependencies.Output('hash', 'children'),
              [dash.dependencies.Input('url', 'hash')])
def display_page(hash_url):
    print ('This is the url hash: {}'.format(hash_url))
    return html.Div([
        html.H3('This is the url hash: {}'.format(hash_url))
    ])


if __name__ == '__main__':
    app.run_server(debug=True)