app.py

'''
main python script
'''

# -*- coding: utf-8 -*-
import base64
import datetime
import io

import dash
import dash_core_components as dcc
import dash_html_components as html
import dash_table_experiments as dt
from dash.dependencies import Input, Output
import pandas as pd

# initialize dash app
app = dash.Dash()

# generates a table (reusable component)
def generate_table(dataframe, max_rows=10):
    return html.Table(
        # Header
        [html.Tr([html.Th(col) for col in dataframe.columns])] +

        # Body
        [html.Tr([
            html.Td(dataframe.iloc[i][col]) for col in dataframe.columns
        ]) for i in range(min(len(dataframe), max_rows))]
    )

# defines front-end layout
app.layout = html.Div(children=[
    html.H1(children='Bank Parser Dashboard'),

    dcc.Upload(
        id='upload-data',
        children=html.Div(children=[
            'Drag and Drop or ',
            html.A('Click to select file.')
        ]),
        style={
            'width': '100%',
            'height': '60px',
            'lineHeight': '60px',
            'borderWidth': '1px',
            'borderStyle': 'dashed',
            'borderRadius': '5px',
            'textAlign': 'center',
            'margin': '10px'
        },
        # Allow multiple files to be uploaded
        multiple=True
    ),
    html.Div(id='output-data-upload'),
    html.Div(dt.DataTable(rows=[{}]), style={'display': 'none'}),

    html.Div(children='''
        For DANY by hackNY :)
    '''),

])


def parse_contents(contents, filename, date):
    content_type, content_string = contents.split(',')
    decoded = base64.b64decode(content_string)
    try:
        if 'csv' in filename:
            # Assume that the user uploaded a CSV file
            df = pd.read_csv(
                io.StringIO(decoded.decode('utf-8')))
        elif 'xls' in filename:
            # Assume that the user uploaded an excel file
            df = pd.read_excel(io.BytesIO(decoded))
        else:
            return html.Div('Make sure the file type is .csv or .xls')
    except IOError as e:
        print(e)
        return html.Div([
            'Error occured uploading file.'
        ])

    x = [pd.to_datetime(date, format='%m/%d') for date in df['transaction_date']]
    y = [abs(float(a)) for a in df['amount']]

    return html.Div([
        html.H5(filename),
        html.H6(datetime.datetime.fromtimestamp(date)),

        # graph
        dcc.Graph(
            id='example-graph',
            figure={
                'data': [
                    {'x': x, 'y': y, 'type': 'bar', 'name': 'Transactions'}
                ],
                'layout': {
                    'title': 'Transactions'
                }
            }
        ),

        # table
        #generate_table(df)
        # Use the DataTable prototype component:
        # github.com/plotly/dash-table-experiments
        dt.DataTable(rows=df.to_dict('records'),
        row_selectable=True,
        filterable=True,
        sortable=True),

        html.Hr(),  # horizontal line

        # For debugging, display the raw contents provided by the web browser
        html.Div('Raw Content'),
        html.Pre(contents[0:200] + '...', style={
            'whiteSpace': 'pre-wrap',
            'wordBreak': 'break-all'
        })
    ])


@app.callback(Output('output-data-upload', 'children'),
              [Input('upload-data', 'contents'),
               Input('upload-data', 'filename'),
               Input('upload-data', 'last_modified')])
def update_output(list_of_contents, list_of_names, list_of_dates):
    if list_of_contents is None:
        return html.Div([
            'Parsed empty contents. This file may not be in a good bank statement format.'
            ])
    try:
        children = [
            parse_contents(c, n, d) for c, n, d in
            zip(list_of_contents, list_of_names, list_of_dates)]
        return children
    except Exception as e:
        return html.Div([
            'Error occured while parsing contents.'
            ])
# starts app from command line, run Flask server
if __name__ == '__main__':
    app.run_server(debug=True)