Can’t debug functions if they have an error in it?

Dash Python
9

I looked at this answer: DatePickerRange to Update Data Table

But I think there is an error in it as there is no df.to_dict(‘rows’). It probably should be 'records' to update data in a DataTable

But I get the point that data and columns need to update separately. So I reorganized my layout and callbacks and i’m still failing silently.
Part of my layout:

DataTable(
        id="conversion-table",
        data=[],
        style_cell={'textAlign': 'left'},
        style_data_conditional=[{
            'if': {'row_index': 'odd'},
            'backgroundColor': 'rgb(248,248,248)'
        }],
        style_header={
            'backgroundColor': 'rgb(230,230,230)',
            'fontWeight': 'bold'
        },
    ),
    html.Div(
        html.H5("Nutrients")
    ),
    html.Br(),
    DataTable(
        id="nutrients-table",
        data=[],
        style_cell_conditional=[{
            'if': {'column_id': c},
            'textAlign': 'left'
        } for c in ['Name']
        ],
        style_data_conditional=[{
            'if': {'row_index': 'odd'},
            'backgroundColor': 'rgb(248,248,248)'
        }],
        style_header={
            'backgroundColor': 'rgb(230,230,230)',
            'fontWeight': 'bold'
        },
    ),

and my callbacks, not even to update but just to show the tables as they start off blank with data=[] me thinks.

@app.callback(
        Output('table-foodgroup-source', 'children'),
        Output('conversion-table', 'data'),
        Output('conversions-table', 'columns'),
        Output('nutrients-table', 'data'),
        Output('nutrients-table', 'columns'),
        Input('search-ingredient', 'value')
    )
    def show_tables(ingredient):
        '''
        return top table, conversions table, nutrients table, yield table,
        refuse table
        '''
        food_id = food_to_id_dict[ingredient]
        food = CNFFoodName.objects.get(id=str(food_id))
        food_grp = food.food_group.name
        food_src = food.food_source.description
        food_sci_name = "n/a"
        if food.scientific_name:
            food_sci_name = food.scientific_name
        # table for food group, source, scientific name
        food_group_table = html.Table([
                                html.Thead([
                                    html.Tr([html.Th("Group"), html.Th("Source"), html.Th("Scientific Name")])
                                ]),
                                html.Tbody([
                                    html.Tr([
                                        html.Td(food_grp),html.Td(food_src),html.Td(food_sci_name)
                                    ])
                                ])
                            ])

        conversions_df = make_conversions_df(food_id)
        #conversions_cols = [{"id": i, "name": conversions_df.columns[i]} for i in range(len(conversions_df.columns))]
        conversions_cols = [{"name": i, "id": i} for i in conversions_df.columns]
        conversions_data = conversions_df.to_dict('records')

        nutrients_df = make_nutrients_df(food_id)
        #nutrients_cols = [{"id": i, "name": nutrients_df.columns[i]} for i in range(len(nutrients_df.columns))]
        nutrients_cols = [{"name": i, "id": i} for i in nutrients_df.columns]
        nutrients_data = nutrients_df.to_dict('records')
        #nutrients_table = make_nutrients_table(nutrients_df)

        return food_group_table, conversions_data, conversions_cols,\
               nutrients_data, nutrients_cols

Not even that first food-group table that is a plaint html.Table is outputting. My other callback that depends on the same input is working. This is sad.