Create an api using dash

Dash Python
1

I have created a dashboard using plotly dash. Now I wish to create an API so that the output of the analytical calculations done to show in the dashboard can be accessed from a different platform.
I can’t find a way to directly do this using just Dash. I found a couple of articles stating how dash can be embedded into a flask app. But I was wondering if there’s a way that the api can be built using just dash.

2

You can add API endpoints to your Dash app by accessing the underlying server connection. Check out this forum post for more information.

How to add restufl api endpoints to a dash app

3

I checked out that post but the issue is that when callbacks are used, the output of the callback doesn’t get accepted by the flask endpoint function. So I can’t export those outputs. Here is a simple code I’ve been trying:

df = pd.DataFrame({‘name’: [‘A’, ‘B’, ‘C’, ‘D’],
‘value’: [10, 20, 30, 40]
})

server = Flask(name)
app = dash.Dash(name=‘app1’, server=server, url_base_pathname=’/app1/’)

app.layout = dbc.Container([
dbc.Row([
dbc.Col([
dcc.Dropdown(id=‘dropdown’,
options=[{‘label’: k, ‘value’: v} for k, v in zip(df[‘name’], df[‘value’])],
value=10)
], width=4),

    dbc.Col([
        html.P(id='ptext')
    ])
])

])

@app.callback(
Output(‘intermediate_value’, ‘data’),
Input(‘dropdown’, ‘value’)
)
def ptext(dropdown):
text = dropdown + 5
return text

@server.route(’/app1/route1’)
def app2(ptext):
text = ptext()
return text

if name == ‘main’:
server.run(debug=True, port=8050)

This code throws the error:
TypeError: app2() missing 1 required positional argument: ‘ptext’

4

Specifically look at the solution of the post. They define the class endpoint and then add it as a resource. I’m guessing from your error you the server is not calling app2 with a parameter like you defined.