viz.py

"""This module contains the 'Viz' objects

These objects represent the backend of all the visualizations that
Superset can render.
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

from collections import defaultdict
import copy
from datetime import datetime, timedelta
import hashlib
import inspect
from itertools import product
import logging
import traceback
import uuid
import zlib

from dateutil import relativedelta as rdelta
from flask import request
from flask_babel import lazy_gettext as _
import geohash
from markdown import markdown
import numpy as np
import pandas as pd
from pandas.tseries.frequencies import to_offset
import simplejson as json
from six import PY3, string_types, text_type
from six.moves import reduce

from superset import app, cache, get_manifest_file, utils
from superset.utils import DTTM_ALIAS, merge_extra_filters

config = app.config
stats_logger = config.get('STATS_LOGGER')


class BaseViz(object):

    """All visualizations derive this base class"""

    viz_type = None
    verbose_name = 'Base Viz'
    credits = ''
    is_timeseries = False
    default_fillna = 0

    def __init__(self, datasource, form_data):
        if not datasource:
            raise Exception(_('Viz is missing a datasource'))
        self.datasource = datasource
        self.request = request
        self.viz_type = form_data.get('viz_type')
        self.form_data = form_data

        self.query = ''
        self.token = self.form_data.get(
            'token', 'token_' + uuid.uuid4().hex[:8])
        self.metrics = self.form_data.get('metrics') or []
        self.groupby = self.form_data.get('groupby') or []
        self.annotation_layers = []

        self.status = None
        self.error_message = None

    def get_fillna_for_type(self, col_type):
        """Returns the value for use as filler for a specific Column.type"""
        if col_type:
            if col_type == 'TEXT' or col_type.startswith('VARCHAR'):
                return ' NULL'
        return self.default_fillna

    def get_fillna_for_columns(self, columns=None):
        """Returns a dict or scalar that can be passed to DataFrame.fillna"""
        if columns is None:
            return self.default_fillna
        columns_types = self.datasource.columns_types
        fillna = {c: self.get_fillna_for_type(columns_types.get(c)) for c in columns}
        return fillna

    def get_df(self, query_obj=None):
        """Returns a pandas dataframe based on the query object"""
        if not query_obj:
            query_obj = self.query_obj()

        self.error_msg = ''
        self.results = None

        timestamp_format = None
        if self.datasource.type == 'table':
            dttm_col = self.datasource.get_col(query_obj['granularity'])
            if dttm_col:
                timestamp_format = dttm_col.python_date_format

        # The datasource here can be different backend but the interface is common
        self.results = self.datasource.query(query_obj)
        self.query = self.results.query
        self.status = self.results.status
        self.error_message = self.results.error_message

        df = self.results.df
        # Transform the timestamp we received from database to pandas supported
        # datetime format. If no python_date_format is specified, the pattern will
        # be considered as the default ISO date format
        # If the datetime format is unix, the parse will use the corresponding
        # parsing logic.
        if df is None or df.empty:
            self.status = utils.QueryStatus.FAILED
            if not self.error_message:
                self.error_message = 'No data.'
            return pd.DataFrame()
        else:
            if DTTM_ALIAS in df.columns:
                if timestamp_format in ('epoch_s', 'epoch_ms'):
                    df[DTTM_ALIAS] = pd.to_datetime(df[DTTM_ALIAS], utc=False)
                else:
                    df[DTTM_ALIAS] = pd.to_datetime(
                        df[DTTM_ALIAS], utc=False, format=timestamp_format)
                if self.datasource.offset:
                    df[DTTM_ALIAS] += timedelta(hours=self.datasource.offset)
            df.replace([np.inf, -np.inf], np.nan)
            fillna = self.get_fillna_for_columns(df.columns)
            df = df.fillna(fillna)
        return df

    def query_obj(self):
        """Building a query object"""
        form_data = self.form_data
        gb = form_data.get('groupby') or []
        metrics = form_data.get('metrics') or []
        columns = form_data.get('columns') or []
        groupby = []
        for o in gb + columns:
            if o not in groupby:
                groupby.append(o)

        is_timeseries = self.is_timeseries
        if DTTM_ALIAS in groupby:
            groupby.remove(DTTM_ALIAS)
            is_timeseries = True

        # Add extra filters into the query form data
        merge_extra_filters(form_data)

        granularity = (
            form_data.get('granularity') or
            form_data.get('granularity_sqla')
        )
        limit = int(form_data.get('limit') or 0)
        timeseries_limit_metric = form_data.get('timeseries_limit_metric')
        row_limit = int(form_data.get('row_limit') or config.get('ROW_LIMIT'))

        # default order direction
        order_desc = form_data.get('order_desc', True)

        since = form_data.get('since', '')
        until = form_data.get('until', 'now')

        # Backward compatibility hack
        if since:
            since_words = since.split(' ')
            grains = ['days', 'years', 'hours', 'day', 'year', 'weeks']
            if (len(since_words) == 2 and since_words[1] in grains):
                since += ' ago'

        from_dttm = utils.parse_human_datetime(since)

        to_dttm = utils.parse_human_datetime(until)
        if from_dttm and to_dttm and from_dttm > to_dttm:
            raise Exception(_('From date cannot be larger than to date'))

        self.from_dttm = from_dttm
        self.to_dttm = to_dttm
        self.annotation_layers = form_data.get('annotation_layers') or []

        # extras are used to query elements specific to a datasource type
        # for instance the extra where clause that applies only to Tables
        extras = {
            'where': form_data.get('where', ''),
            'having': form_data.get('having', ''),
            'having_druid': form_data.get('having_filters', []),
            'time_grain_sqla': form_data.get('time_grain_sqla', ''),
            'druid_time_origin': form_data.get('druid_time_origin', ''),
        }
        filters = form_data.get('filters', [])
        d = {
            'granularity': granularity,
            'from_dttm': from_dttm,
            'to_dttm': to_dttm,
            'is_timeseries': is_timeseries,
            'groupby': groupby,
            'metrics': metrics,
            'row_limit': row_limit,
            'filter': filters,
            'timeseries_limit': limit,
            'extras': extras,
            'timeseries_limit_metric': timeseries_limit_metric,
            'form_data': form_data,
            'order_desc': order_desc,
        }
        return d

    @property
    def cache_timeout(self):
        if self.form_data.get('cache_timeout'):
            return int(self.form_data.get('cache_timeout'))
        if self.datasource.cache_timeout:
            return self.datasource.cache_timeout
        if (
                hasattr(self.datasource, 'database') and
                self.datasource.database.cache_timeout):
            return self.datasource.database.cache_timeout
        return config.get('CACHE_DEFAULT_TIMEOUT')

    def get_json(self, force=False):
        return json.dumps(
            self.get_payload(force),
            default=utils.json_int_dttm_ser, ignore_nan=True)

    @property
    def cache_key(self):
        form_data = self.form_data.copy()
        merge_extra_filters(form_data)
        s = str([(k, form_data[k]) for k in sorted(form_data.keys())])
        return hashlib.md5(s.encode('utf-8')).hexdigest()

    def get_annotations(self):
        """Fetches the annotations for the specified layers and date range"""
        annotations = []
        if self.annotation_layers:
            from superset.models.annotations import Annotation
            from superset import db
            qry = (
                db.session
                .query(Annotation)
                .filter(Annotation.layer_id.in_(self.annotation_layers)))
            if self.from_dttm:
                qry = qry.filter(Annotation.start_dttm >= self.from_dttm)
            if self.to_dttm:
                qry = qry.filter(Annotation.end_dttm <= self.to_dttm)
            annotations = [o.data for o in qry.all()]
        return annotations

    def get_payload(self, force=False):
        """Handles caching around the json payload retrieval"""
        cache_key = self.cache_key
        payload = None
        if not force and cache:
            payload = cache.get(cache_key)

        if payload:
            stats_logger.incr('loaded_from_cache')
            is_cached = True
            try:
                cached_data = zlib.decompress(payload)
                if PY3:
                    cached_data = cached_data.decode('utf-8')
                payload = json.loads(cached_data)
            except Exception as e:
                logging.error('Error reading cache: ' +
                              utils.error_msg_from_exception(e))
                payload = None
                return []
            logging.info('Serving from cache')

        if not payload:
            stats_logger.incr('loaded_from_source')
            data = None
            is_cached = False
            cache_timeout = self.cache_timeout
            stacktrace = None
            annotations = []
            rowcount = None
            try:
                df = self.get_df()
                if not self.error_message:
                    data = self.get_data(df)
                annotations = self.get_annotations()
                rowcount = len(df.index)
            except Exception as e:
                logging.exception(e)
                if not self.error_message:
                    self.error_message = str(e)
                self.status = utils.QueryStatus.FAILED
                data = None
                stacktrace = traceback.format_exc()
            payload = {
                'cache_key': cache_key,
                'cache_timeout': cache_timeout,
                'data': data,
                'error': self.error_message,
                'form_data': self.form_data,
                'query': self.query,
                'status': self.status,
                'stacktrace': stacktrace,
                'annotations': annotations,
                'rowcount': rowcount,
            }
            payload['cached_dttm'] = datetime.utcnow().isoformat().split('.')[0]
            logging.info('Caching for the next {} seconds'.format(
                cache_timeout))
            data = self.json_dumps(payload)
            if PY3:
                data = bytes(data, 'utf-8')
            if cache and self.status != utils.QueryStatus.FAILED:
                try:
                    cache.set(
                        cache_key,
                        zlib.compress(data),
                        timeout=cache_timeout)
                except Exception as e:
                    # cache.set call can fail if the backend is down or if
                    # the key is too large or whatever other reasons
                    logging.warning('Could not cache key {}'.format(cache_key))
                    logging.exception(e)
                    cache.delete(cache_key)
        payload['is_cached'] = is_cached
        return payload

    def json_dumps(self, obj):
        return json.dumps(obj, default=utils.json_int_dttm_ser, ignore_nan=True)

    @property
    def data(self):
        """This is the data object serialized to the js layer"""
        content = {
            'form_data': self.form_data,
            'token': self.token,
            'viz_name': self.viz_type,
            'filter_select_enabled': self.datasource.filter_select_enabled,
        }
        return content

    def get_csv(self):
        df = self.get_df()
        include_index = not isinstance(df.index, pd.RangeIndex)
        return df.to_csv(index=include_index, **config.get('CSV_EXPORT'))

    def get_data(self, df):
        return []

    @property
    def json_data(self):
        return json.dumps(self.data)


class TableViz(BaseViz):

    """A basic html table that is sortable and searchable"""

    viz_type = 'table'
    verbose_name = _('Table View')
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'
    is_timeseries = False

    def should_be_timeseries(self):
        fd = self.form_data
        # TODO handle datasource-type-specific code in datasource
        conditions_met = (
            (fd.get('granularity') and fd.get('granularity') != 'all') or
            (fd.get('granularity_sqla') and fd.get('time_grain_sqla'))
        )
        if fd.get('include_time') and not conditions_met:
            raise Exception(_(
                'Pick a granularity in the Time section or '
                "uncheck 'Include Time'"))
        return fd.get('include_time')

    def query_obj(self):
        d = super(TableViz, self).query_obj()
        fd = self.form_data

        if fd.get('all_columns') and (fd.get('groupby') or fd.get('metrics')):
            raise Exception(_(
                'Choose either fields to [Group By] and [Metrics] or '
                '[Columns], not both'))

        sort_by = fd.get('timeseries_limit_metric')
        if fd.get('all_columns'):
            d['columns'] = fd.get('all_columns')
            d['groupby'] = []
            order_by_cols = fd.get('order_by_cols') or []
            d['orderby'] = [json.loads(t) for t in order_by_cols]
        elif sort_by:
            if sort_by not in d['metrics']:
                d['metrics'] += [sort_by]
            d['orderby'] = [(sort_by, not fd.get('order_desc', True))]

        # Add all percent metrics that are not already in the list
        if 'percent_metrics' in fd:
            d['metrics'] = d['metrics'] + list(filter(
                lambda m: m not in d['metrics'],
                fd['percent_metrics'],
            ))

        d['is_timeseries'] = self.should_be_timeseries()
        return d

    def get_data(self, df):
        fd = self.form_data
        if not self.should_be_timeseries() and DTTM_ALIAS in df:
            del df[DTTM_ALIAS]

        # Sum up and compute percentages for all percent metrics
        percent_metrics = fd.get('percent_metrics', [])
        if len(percent_metrics):
            percent_metrics = list(filter(lambda m: m in df, percent_metrics))
            metric_sums = {
                m: reduce(lambda a, b: a + b, df[m])
                for m in percent_metrics
            }
            metric_percents = {
                m: list(map(lambda a: a / metric_sums[m], df[m]))
                for m in percent_metrics
            }
            for m in percent_metrics:
                m_name = '%' + m
                df[m_name] = pd.Series(metric_percents[m], name=m_name)
            # Remove metrics that are not in the main metrics list
            for m in filter(
                lambda m: m not in fd['metrics'] and m in df.columns,
                percent_metrics,
            ):
                del df[m]

        return dict(
            records=df.to_dict(orient='records'),
            columns=list(df.columns),
        )

    def json_dumps(self, obj):
        if self.form_data.get('all_columns'):
            return json.dumps(obj, default=utils.json_iso_dttm_ser)
        else:
            return super(TableViz, self).json_dumps(obj)


class TimeTableViz(BaseViz):

    """A data table with rich time-series related columns"""

    viz_type = 'time_table'
    verbose_name = _('Time Table View')
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'
    is_timeseries = True

    def query_obj(self):
        d = super(TimeTableViz, self).query_obj()
        fd = self.form_data

        if not fd.get('metrics'):
            raise Exception(_('Pick at least one metric'))

        if fd.get('groupby') and len(fd.get('metrics')) > 1:
            raise Exception(_(
                "When using 'Group By' you are limited to use a single metric"))
        return d

    def get_data(self, df):
        fd = self.form_data
        values = self.metrics
        columns = None
        if fd.get('groupby'):
            values = self.metrics[0]
            columns = fd.get('groupby')
        pt = df.pivot_table(
            index=DTTM_ALIAS,
            columns=columns,
            values=values)
        pt.index = pt.index.map(str)
        pt = pt.sort_index()
        return dict(
            records=pt.to_dict(orient='index'),
            columns=list(pt.columns),
            is_group_by=len(fd.get('groupby')) > 0,
        )


class PivotTableViz(BaseViz):

    """A pivot table view, define your rows, columns and metrics"""

    viz_type = 'pivot_table'
    verbose_name = _('Pivot Table')
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'
    is_timeseries = False

    def query_obj(self):
        d = super(PivotTableViz, self).query_obj()
        groupby = self.form_data.get('groupby')
        columns = self.form_data.get('columns')
        metrics = self.form_data.get('metrics')
        if not columns:
            columns = []
        if not groupby:
            groupby = []
        if not groupby:
            raise Exception(_("Please choose at least one 'Group by' field "))
        if not metrics:
            raise Exception(_('Please choose at least one metric'))
        if (
                any(v in groupby for v in columns) or
                any(v in columns for v in groupby)):
            raise Exception(_("Group By' and 'Columns' can't overlap"))
        return d

    def get_data(self, df):
        if (
                self.form_data.get('granularity') == 'all' and
                DTTM_ALIAS in df):
            del df[DTTM_ALIAS]
        df = df.pivot_table(
            index=self.form_data.get('groupby'),
            columns=self.form_data.get('columns'),
            values=self.form_data.get('metrics'),
            aggfunc=self.form_data.get('pandas_aggfunc'),
            margins=self.form_data.get('pivot_margins'),
        )
        # Display metrics side by side with each column
        if self.form_data.get('combine_metric'):
            df = df.stack(0).unstack()
        return dict(
            columns=list(df.columns),
            html=df.to_html(
                na_rep='',
                classes=(
                    'dataframe table table-striped table-bordered '
                    'table-condensed table-hover').split(' ')),
        )


class MarkupViz(BaseViz):

    """Use html or markdown to create a free form widget"""

    viz_type = 'markup'
    verbose_name = _('Markup')
    is_timeseries = False

    def get_df(self):
        return True

    def get_data(self, df):
        markup_type = self.form_data.get('markup_type')
        code = self.form_data.get('code', '')
        if markup_type == 'markdown':
            code = markdown(code)
        return dict(html=code, theme_css=get_manifest_file('theme.css'))


class SeparatorViz(MarkupViz):

    """Use to create section headers in a dashboard, similar to `Markup`"""

    viz_type = 'separator'
    verbose_name = _('Separator')


class WordCloudViz(BaseViz):

    """Build a colorful word cloud

    Uses the nice library at:
    https://github.com/jasondavies/d3-cloud
    """

    viz_type = 'word_cloud'
    verbose_name = _('Word Cloud')
    is_timeseries = False

    def query_obj(self):
        d = super(WordCloudViz, self).query_obj()

        d['metrics'] = [self.form_data.get('metric')]
        d['groupby'] = [self.form_data.get('series')]
        return d

    def get_data(self, df):
        # Ordering the columns
        df = df[[self.form_data.get('series'), self.form_data.get('metric')]]
        # Labeling the columns for uniform json schema
        df.columns = ['text', 'size']
        return df.to_dict(orient='records')


class TreemapViz(BaseViz):

    """Tree map visualisation for hierarchical data."""

    viz_type = 'treemap'
    verbose_name = _('Treemap')
    credits = '<a href="https://d3js.org">d3.js</a>'
    is_timeseries = False

    def _nest(self, metric, df):
        nlevels = df.index.nlevels
        if nlevels == 1:
            result = [{'name': n, 'value': v}
                      for n, v in zip(df.index, df[metric])]
        else:
            result = [{'name': l, 'children': self._nest(metric, df.loc[l])}
                      for l in df.index.levels[0]]
        return result

    def get_data(self, df):
        df = df.set_index(self.form_data.get('groupby'))
        chart_data = [{'name': metric, 'children': self._nest(metric, df)}
                      for metric in df.columns]
        return chart_data


class CalHeatmapViz(BaseViz):

    """Calendar heatmap."""

    viz_type = 'cal_heatmap'
    verbose_name = _('Calendar Heatmap')
    credits = (
        '<a href=https://github.com/wa0x6e/cal-heatmap>cal-heatmap</a>')
    is_timeseries = True

    def get_data(self, df):
        form_data = self.form_data

        df.columns = ['timestamp', 'metric']
        timestamps = {str(obj['timestamp'].value / 10**9):
                      obj.get('metric') for obj in df.to_dict('records')}

        start = utils.parse_human_datetime(form_data.get('since'))
        end = utils.parse_human_datetime(form_data.get('until'))
        domain = form_data.get('domain_granularity')
        diff_delta = rdelta.relativedelta(end, start)
        diff_secs = (end - start).total_seconds()

        if domain == 'year':
            range_ = diff_delta.years + 1
        elif domain == 'month':
            range_ = diff_delta.years * 12 + diff_delta.months + 1
        elif domain == 'week':
            range_ = diff_delta.years * 53 + diff_delta.weeks + 1
        elif domain == 'day':
            range_ = diff_secs // (24 * 60 * 60) + 1
        else:
            range_ = diff_secs // (60 * 60) + 1

        return {
            'timestamps': timestamps,
            'start': start,
            'domain': domain,
            'subdomain': form_data.get('subdomain_granularity'),
            'range': range_,
        }

    def query_obj(self):
        qry = super(CalHeatmapViz, self).query_obj()
        qry['metrics'] = [self.form_data['metric']]
        return qry


class NVD3Viz(BaseViz):

    """Base class for all nvd3 vizs"""

    credits = '<a href="http://nvd3.org/">NVD3.org</a>'
    viz_type = None
    verbose_name = 'Base NVD3 Viz'
    is_timeseries = False


class BoxPlotViz(NVD3Viz):

    """Box plot viz from ND3"""

    viz_type = 'box_plot'
    verbose_name = _('Box Plot')
    sort_series = False
    is_timeseries = True

    def to_series(self, df, classed='', title_suffix=''):
        label_sep = ' - '
        chart_data = []
        for index_value, row in zip(df.index, df.to_dict(orient='records')):
            if isinstance(index_value, tuple):
                index_value = label_sep.join(index_value)
            boxes = defaultdict(dict)
            for (label, key), value in row.items():
                if key == 'median':
                    key = 'Q2'
                boxes[label][key] = value
            for label, box in boxes.items():
                if len(self.form_data.get('metrics')) > 1:
                    # need to render data labels with metrics
                    chart_label = label_sep.join([index_value, label])
                else:
                    chart_label = index_value
                chart_data.append({
                    'label': chart_label,
                    'values': box,
                })
        return chart_data

    def get_data(self, df):
        form_data = self.form_data
        df = df.fillna(0)

        # conform to NVD3 names
        def Q1(series):  # need to be named functions - can't use lambdas
            return np.percentile(series, 25)

        def Q3(series):
            return np.percentile(series, 75)

        whisker_type = form_data.get('whisker_options')
        if whisker_type == 'Tukey':

            def whisker_high(series):
                upper_outer_lim = Q3(series) + 1.5 * (Q3(series) - Q1(series))
                series = series[series <= upper_outer_lim]
                return series[np.abs(series - upper_outer_lim).argmin()]

            def whisker_low(series):
                lower_outer_lim = Q1(series) - 1.5 * (Q3(series) - Q1(series))
                # find the closest value above the lower outer limit
                series = series[series >= lower_outer_lim]
                return series[np.abs(series - lower_outer_lim).argmin()]

        elif whisker_type == 'Min/max (no outliers)':

            def whisker_high(series):
                return series.max()

            def whisker_low(series):
                return series.min()

        elif ' percentiles' in whisker_type:
            low, high = whisker_type.replace(' percentiles', '').split('/')

            def whisker_high(series):
                return np.percentile(series, int(high))

            def whisker_low(series):
                return np.percentile(series, int(low))

        else:
            raise ValueError('Unknown whisker type: {}'.format(whisker_type))

        def outliers(series):
            above = series[series > whisker_high(series)]
            below = series[series < whisker_low(series)]
            # pandas sometimes doesn't like getting lists back here
            return set(above.tolist() + below.tolist())

        aggregate = [Q1, np.median, Q3, whisker_high, whisker_low, outliers]
        df = df.groupby(form_data.get('groupby')).agg(aggregate)
        chart_data = self.to_series(df)
        return chart_data


class BubbleViz(NVD3Viz):

    """Based on the NVD3 bubble chart"""

    viz_type = 'bubble'
    verbose_name = _('Bubble Chart')
    is_timeseries = False

    def query_obj(self):
        form_data = self.form_data
        d = super(BubbleViz, self).query_obj()
        d['groupby'] = [
            form_data.get('entity'),
        ]
        if form_data.get('series'):
            d['groupby'].append(form_data.get('series'))
        self.x_metric = form_data.get('x')
        self.y_metric = form_data.get('y')
        self.z_metric = form_data.get('size')
        self.entity = form_data.get('entity')
        self.series = form_data.get('series') or self.entity
        d['row_limit'] = form_data.get('limit')

        d['metrics'] = [
            self.z_metric,
            self.x_metric,
            self.y_metric,
        ]
        if not all(d['metrics'] + [self.entity]):
            raise Exception(_('Pick a metric for x, y and size'))
        return d

    def get_data(self, df):
        df['x'] = df[[self.x_metric]]
        df['y'] = df[[self.y_metric]]
        df['size'] = df[[self.z_metric]]
        df['shape'] = 'circle'
        df['group'] = df[[self.series]]

        series = defaultdict(list)
        for row in df.to_dict(orient='records'):
            series[row['group']].append(row)
        chart_data = []
        for k, v in series.items():
            chart_data.append({
                'key': k,
                'values': v})
        return chart_data


class BulletViz(NVD3Viz):

    """Based on the NVD3 bullet chart"""

    viz_type = 'bullet'
    verbose_name = _('Bullet Chart')
    is_timeseries = False

    def query_obj(self):
        form_data = self.form_data
        d = super(BulletViz, self).query_obj()
        self.metric = form_data.get('metric')

        def as_strings(field):
            value = form_data.get(field)
            return value.split(',') if value else []

        def as_floats(field):
            return [float(x) for x in as_strings(field)]

        self.ranges = as_floats('ranges')
        self.range_labels = as_strings('range_labels')
        self.markers = as_floats('markers')
        self.marker_labels = as_strings('marker_labels')
        self.marker_lines = as_floats('marker_lines')
        self.marker_line_labels = as_strings('marker_line_labels')

        d['metrics'] = [
            self.metric,
        ]
        if not self.metric:
            raise Exception(_('Pick a metric to display'))
        return d

    def get_data(self, df):
        df = df.fillna(0)
        df['metric'] = df[[self.metric]]
        values = df['metric'].values
        return {
            'measures': values.tolist(),
            'ranges': self.ranges or [0, values.max() * 1.1],
            'rangeLabels': self.range_labels or None,
            'markers': self.markers or None,
            'markerLabels': self.marker_labels or None,
            'markerLines': self.marker_lines or None,
            'markerLineLabels': self.marker_line_labels or None,
        }


class BigNumberViz(BaseViz):

    """Put emphasis on a single metric with this big number viz"""

    viz_type = 'big_number'
    verbose_name = _('Big Number with Trendline')
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'
    is_timeseries = True

    def query_obj(self):
        d = super(BigNumberViz, self).query_obj()
        metric = self.form_data.get('metric')
        if not metric:
            raise Exception(_('Pick a metric!'))
        d['metrics'] = [self.form_data.get('metric')]
        self.form_data['metric'] = metric
        return d

    def get_data(self, df):
        form_data = self.form_data
        df.sort_values(by=df.columns[0], inplace=True)
        compare_lag = form_data.get('compare_lag')
        return {
            'data': df.values.tolist(),
            'compare_lag': compare_lag,
            'compare_suffix': form_data.get('compare_suffix', ''),
        }


class BigNumberTotalViz(BaseViz):

    """Put emphasis on a single metric with this big number viz"""

    viz_type = 'big_number_total'
    verbose_name = _('Big Number')
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'
    is_timeseries = False

    def query_obj(self):
        d = super(BigNumberTotalViz, self).query_obj()
        metric = self.form_data.get('metric')
        if not metric:
            raise Exception(_('Pick a metric!'))
        d['metrics'] = [self.form_data.get('metric')]
        self.form_data['metric'] = metric
        return d

    def get_data(self, df):
        form_data = self.form_data
        df.sort_values(by=df.columns[0], inplace=True)
        return {
            'data': df.values.tolist(),
            'subheader': form_data.get('subheader', ''),
        }


class NVD3TimeSeriesViz(NVD3Viz):

    """A rich line chart component with tons of options"""

    viz_type = 'line'
    verbose_name = _('Time Series - Line Chart')
    sort_series = False
    is_timeseries = True

    def to_series(self, df, classed='', title_suffix=''):
        cols = []
        for col in df.columns:
            if col == '':
                cols.append('N/A')
            elif col is None:
                cols.append('NULL')
            else:
                cols.append(col)
        df.columns = cols
        series = df.to_dict('series')

        chart_data = []
        for name in df.T.index.tolist():
            ys = series[name]
            if df[name].dtype.kind not in 'biufc':
                continue
            series_title = name
            if (
                    isinstance(series_title, (list, tuple)) and
                    len(series_title) > 1 and
                    len(self.metrics) == 1):
                # Removing metric from series name if only one metric
                series_title = series_title[1:]
            if isinstance(series_title, string_types):
                series_title += title_suffix
            elif title_suffix and isinstance(series_title, (list, tuple)):
                series_title = series_title + (title_suffix,)

            values = []
            for ds in df.index:
                if ds in ys:
                    d = {
                        'x': ds,
                        'y': ys[ds],
                    }
                else:
                    d = {}
                values.append(d)

            d = {
                'key': series_title,
                'values': values,
            }
            if classed:
                d['classed'] = classed
            chart_data.append(d)
        return chart_data

    def process_data(self, df, aggregate=False):
        fd = self.form_data
        df = df.fillna(0)
        if fd.get('granularity') == 'all':
            raise Exception(_('Pick a time granularity for your time series'))

        if not aggregate:
            df = df.pivot_table(
                index=DTTM_ALIAS,
                columns=fd.get('groupby'),
                values=fd.get('metrics'))
        else:
            df = df.pivot_table(
                index=DTTM_ALIAS,
                columns=fd.get('groupby'),
                values=fd.get('metrics'),
                fill_value=0,
                aggfunc=sum)

        fm = fd.get('resample_fillmethod')
        if not fm:
            fm = None
        how = fd.get('resample_how')
        rule = fd.get('resample_rule')
        if how and rule:
            df = df.resample(rule, how=how, fill_method=fm)
            if not fm:
                df = df.fillna(0)

        if self.sort_series:
            dfs = df.sum()
            dfs.sort_values(ascending=False, inplace=True)
            df = df[dfs.index]

        if fd.get('contribution'):
            dft = df.T
            df = (dft / dft.sum()).T

        rolling_type = fd.get('rolling_type')
        rolling_periods = int(fd.get('rolling_periods') or 0)
        min_periods = int(fd.get('min_periods') or 0)

        if rolling_type in ('mean', 'std', 'sum') and rolling_periods:
            kwargs = dict(
                arg=df,
                window=rolling_periods,
                min_periods=min_periods)
            if rolling_type == 'mean':
                df = pd.rolling_mean(**kwargs)
            elif rolling_type == 'std':
                df = pd.rolling_std(**kwargs)
            elif rolling_type == 'sum':
                df = pd.rolling_sum(**kwargs)
        elif rolling_type == 'cumsum':
            df = df.cumsum()
        if min_periods:
            df = df[min_periods:]

        num_period_compare = fd.get('num_period_compare')
        if num_period_compare:
            num_period_compare = int(num_period_compare)
            prt = fd.get('period_ratio_type')
            if prt and prt == 'growth':
                df = (df / df.shift(num_period_compare)) - 1
            elif prt and prt == 'value':
                df = df - df.shift(num_period_compare)
            else:
                df = df / df.shift(num_period_compare)

            df = df[num_period_compare:]
        return df

    def get_data(self, df):
        fd = self.form_data
        df = self.process_data(df)
        chart_data = self.to_series(df)

        time_compare = fd.get('time_compare')
        if time_compare:
            query_object = self.query_obj()
            delta = utils.parse_human_timedelta(time_compare)
            query_object['inner_from_dttm'] = query_object['from_dttm']
            query_object['inner_to_dttm'] = query_object['to_dttm']
            query_object['from_dttm'] -= delta
            query_object['to_dttm'] -= delta

            df2 = self.get_df(query_object)
            df2[DTTM_ALIAS] += delta
            df2 = self.process_data(df2)
            chart_data += self.to_series(
                df2, classed='superset', title_suffix='---')
            chart_data = sorted(chart_data, key=lambda x: x['key'])
        return chart_data


class NVD3DualLineViz(NVD3Viz):

    """A rich line chart with dual axis"""

    viz_type = 'dual_line'
    verbose_name = _('Time Series - Dual Axis Line Chart')
    sort_series = False
    is_timeseries = True

    def query_obj(self):
        d = super(NVD3DualLineViz, self).query_obj()
        m1 = self.form_data.get('metric')
        m2 = self.form_data.get('metric_2')
        d['metrics'] = [m1, m2]
        if not m1:
            raise Exception(_('Pick a metric for left axis!'))
        if not m2:
            raise Exception(_('Pick a metric for right axis!'))
        if m1 == m2:
            raise Exception(_('Please choose different metrics'
                            ' on left and right axis'))
        return d

    def to_series(self, df, classed=''):
        cols = []
        for col in df.columns:
            if col == '':
                cols.append('N/A')
            elif col is None:
                cols.append('NULL')
            else:
                cols.append(col)
        df.columns = cols
        series = df.to_dict('series')
        chart_data = []
        metrics = [
            self.form_data.get('metric'),
            self.form_data.get('metric_2'),
        ]
        for i, m in enumerate(metrics):
            ys = series[m]
            if df[m].dtype.kind not in 'biufc':
                continue
            series_title = m
            d = {
                'key': series_title,
                'classed': classed,
                'values': [
                    {'x': ds, 'y': ys[ds] if ds in ys else None}
                    for ds in df.index
                ],
                'yAxis': i + 1,
                'type': 'line',
            }
            chart_data.append(d)
        return chart_data

    def get_data(self, df):
        fd = self.form_data
        df = df.fillna(0)

        if self.form_data.get('granularity') == 'all':
            raise Exception(_('Pick a time granularity for your time series'))

        metric = fd.get('metric')
        metric_2 = fd.get('metric_2')
        df = df.pivot_table(
            index=DTTM_ALIAS,
            values=[metric, metric_2])

        chart_data = self.to_series(df)
        return chart_data


class NVD3TimeSeriesBarViz(NVD3TimeSeriesViz):

    """A bar chart where the x axis is time"""

    viz_type = 'bar'
    sort_series = True
    verbose_name = _('Time Series - Bar Chart')


class NVD3TimePivotViz(NVD3TimeSeriesViz):

    """Time Series - Periodicity Pivot"""

    viz_type = 'time_pivot'
    sort_series = True
    verbose_name = _('Time Series - Period Pivot')

    def query_obj(self):
        d = super(NVD3TimePivotViz, self).query_obj()
        d['metrics'] = [self.form_data.get('metric')]
        return d

    def get_data(self, df):
        fd = self.form_data
        df = self.process_data(df)
        freq = to_offset(fd.get('freq'))
        freq.normalize = True
        df[DTTM_ALIAS] = df.index.map(freq.rollback)
        df['ranked'] = df[DTTM_ALIAS].rank(method='dense', ascending=False) - 1
        df.ranked = df.ranked.map(int)
        df['series'] = '-' + df.ranked.map(str)
        df['series'] = df['series'].str.replace('-0', 'current')
        rank_lookup = {
            row['series']: row['ranked']
            for row in df.to_dict(orient='records')
        }
        max_ts = df[DTTM_ALIAS].max()
        max_rank = df['ranked'].max()
        df[DTTM_ALIAS] = df.index + (max_ts - df[DTTM_ALIAS])
        df = df.pivot_table(
            index=DTTM_ALIAS,
            columns='series',
            values=fd.get('metric'))
        chart_data = self.to_series(df)
        for serie in chart_data:
            serie['rank'] = rank_lookup[serie['key']]
            serie['perc'] = 1 - (serie['rank'] / (max_rank + 1))
        return chart_data


class NVD3CompareTimeSeriesViz(NVD3TimeSeriesViz):

    """A line chart component where you can compare the % change over time"""

    viz_type = 'compare'
    verbose_name = _('Time Series - Percent Change')


class NVD3TimeSeriesStackedViz(NVD3TimeSeriesViz):

    """A rich stack area chart"""

    viz_type = 'area'
    verbose_name = _('Time Series - Stacked')
    sort_series = True


class DistributionPieViz(NVD3Viz):

    """Annoy visualization snobs with this controversial pie chart"""

    viz_type = 'pie'
    verbose_name = _('Distribution - NVD3 - Pie Chart')
    is_timeseries = False

    def get_data(self, df):
        df = df.pivot_table(
            index=self.groupby,
            values=[self.metrics[0]])
        df.sort_values(by=self.metrics[0], ascending=False, inplace=True)
        df = df.reset_index()
        df.columns = ['x', 'y']
        return df.to_dict(orient='records')


class HistogramViz(BaseViz):

    """Histogram"""

    viz_type = 'histogram'
    verbose_name = _('Histogram')
    is_timeseries = False

    def query_obj(self):
        """Returns the query object for this visualization"""
        d = super(HistogramViz, self).query_obj()
        d['row_limit'] = self.form_data.get(
            'row_limit', int(config.get('VIZ_ROW_LIMIT')))
        numeric_column = self.form_data.get('all_columns_x')
        if numeric_column is None:
            raise Exception(_('Must have one numeric column specified'))
        d['columns'] = [numeric_column]
        return d

    def get_data(self, df):
        """Returns the chart data"""
        chart_data = df[df.columns[0]].values.tolist()
        return chart_data


class DistributionBarViz(DistributionPieViz):

    """A good old bar chart"""

    viz_type = 'dist_bar'
    verbose_name = _('Distribution - Bar Chart')
    is_timeseries = False

    def query_obj(self):
        d = super(DistributionBarViz, self).query_obj()  # noqa
        fd = self.form_data
        if (
            len(d['groupby']) <
            len(fd.get('groupby') or []) + len(fd.get('columns') or [])
        ):
            raise Exception(
                _("Can't have overlap between Series and Breakdowns"))
        if not fd.get('metrics'):
            raise Exception(_('Pick at least one metric'))
        if not fd.get('groupby'):
            raise Exception(_('Pick at least one field for [Series]'))
        return d

    def get_data(self, df):
        fd = self.form_data

        row = df.groupby(self.groupby).sum()[self.metrics[0]].copy()
        row.sort_values(ascending=False, inplace=True)
        columns = fd.get('columns') or []
        pt = df.pivot_table(
            index=self.groupby,
            columns=columns,
            values=self.metrics)
        if fd.get('contribution'):
            pt = pt.fillna(0)
            pt = pt.T
            pt = (pt / pt.sum()).T
        pt = pt.reindex(row.index)
        chart_data = []
        for name, ys in pt.iteritems():
            if pt[name].dtype.kind not in 'biufc' or name in self.groupby:
                continue
            if isinstance(name, string_types):
                series_title = name
            elif len(self.metrics) > 1:
                series_title = ', '.join(name)
            else:
                l = [str(s) for s in name[1:]]  # noqa: E741
                series_title = ', '.join(l)
            values = []
            for i, v in ys.iteritems():
                x = i
                if isinstance(x, (tuple, list)):
                    x = ', '.join([text_type(s) for s in x])
                else:
                    x = text_type(x)
                values.append({
                    'x': x,
                    'y': v,
                })
            d = {
                'key': series_title,
                'values': values,
            }
            chart_data.append(d)
        return chart_data


class SunburstViz(BaseViz):

    """A multi level sunburst chart"""

    viz_type = 'sunburst'
    verbose_name = _('Sunburst')
    is_timeseries = False
    credits = (
        'Kerry Rodden '
        '@<a href="https://bl.ocks.org/kerryrodden/7090426">bl.ocks.org</a>')

    def get_data(self, df):

        # if m1 == m2 duplicate the metric column
        cols = self.form_data.get('groupby')
        metric = self.form_data.get('metric')
        secondary_metric = self.form_data.get('secondary_metric')
        if metric == secondary_metric:
            ndf = df
            ndf.columns = [cols + ['m1', 'm2']]
        else:
            cols += [
                self.form_data['metric'], self.form_data['secondary_metric']]
            ndf = df[cols]
        return json.loads(ndf.to_json(orient='values'))  # TODO fix this nonsense

    def query_obj(self):
        qry = super(SunburstViz, self).query_obj()
        qry['metrics'] = [
            self.form_data['metric'], self.form_data['secondary_metric']]
        return qry


class SankeyViz(BaseViz):

    """A Sankey diagram that requires a parent-child dataset"""

    viz_type = 'sankey'
    verbose_name = _('Sankey')
    is_timeseries = False
    credits = '<a href="https://www.npmjs.com/package/d3-sankey">d3-sankey on npm</a>'

    def query_obj(self):
        qry = super(SankeyViz, self).query_obj()
        if len(qry['groupby']) != 2:
            raise Exception(_('Pick exactly 2 columns as [Source / Target]'))
        qry['metrics'] = [
            self.form_data['metric']]
        return qry

    def get_data(self, df):
        df.columns = ['source', 'target', 'value']
        recs = df.to_dict(orient='records')

        hierarchy = defaultdict(set)
        for row in recs:
            hierarchy[row['source']].add(row['target'])

        def find_cycle(g):
            """Whether there's a cycle in a directed graph"""
            path = set()

            def visit(vertex):
                path.add(vertex)
                for neighbour in g.get(vertex, ()):
                    if neighbour in path or visit(neighbour):
                        return (vertex, neighbour)
                path.remove(vertex)

            for v in g:
                cycle = visit(v)
                if cycle:
                    return cycle

        cycle = find_cycle(hierarchy)
        if cycle:
            raise Exception(_(
                "There's a loop in your Sankey, please provide a tree. "
                "Here's a faulty link: {}").format(cycle))
        return recs


class DirectedForceViz(BaseViz):

    """An animated directed force layout graph visualization"""

    viz_type = 'directed_force'
    verbose_name = _('Directed Force Layout')
    credits = 'd3noob @<a href="http://bl.ocks.org/d3noob/5141278">bl.ocks.org</a>'
    is_timeseries = False

    def query_obj(self):
        qry = super(DirectedForceViz, self).query_obj()
        if len(self.form_data['groupby']) != 2:
            raise Exception(_("Pick exactly 2 columns to 'Group By'"))
        qry['metrics'] = [self.form_data['metric']]
        return qry

    def get_data(self, df):
        df.columns = ['source', 'target', 'value']
        return df.to_dict(orient='records')


class ChordViz(BaseViz):

    """A Chord diagram"""

    viz_type = 'chord'
    verbose_name = _('Directed Force Layout')
    credits = '<a href="https://github.com/d3/d3-chord">Bostock</a>'
    is_timeseries = False

    def query_obj(self):
        qry = super(ChordViz, self).query_obj()
        fd = self.form_data
        qry['groupby'] = [fd.get('groupby'), fd.get('columns')]
        qry['metrics'] = [fd.get('metric')]
        return qry

    def get_data(self, df):
        df.columns = ['source', 'target', 'value']

        # Preparing a symetrical matrix like d3.chords calls for
        nodes = list(set(df['source']) | set(df['target']))
        matrix = {}
        for source, target in product(nodes, nodes):
            matrix[(source, target)] = 0
        for source, target, value in df.to_records(index=False):
            matrix[(source, target)] = value
        m = [[matrix[(n1, n2)] for n1 in nodes] for n2 in nodes]
        return {
            'nodes': list(nodes),
            'matrix': m,
        }


class CountryMapViz(BaseViz):

    """A country centric"""

    viz_type = 'country_map'
    verbose_name = _('Country Map')
    is_timeseries = False
    credits = 'From bl.ocks.org By john-guerra'

    def query_obj(self):
        qry = super(CountryMapViz, self).query_obj()
        qry['metrics'] = [
            self.form_data['metric']]
        qry['groupby'] = [self.form_data['entity']]
        return qry

    def get_data(self, df):
        fd = self.form_data
        cols = [fd.get('entity')]
        metric = fd.get('metric')
        cols += [metric]
        ndf = df[cols]
        df = ndf
        df.columns = ['country_id', 'metric']
        d = df.to_dict(orient='records')
        return d


class WorldMapViz(BaseViz):

    """A country centric world map"""

    viz_type = 'world_map'
    verbose_name = _('World Map')
    is_timeseries = False
    credits = 'datamaps on <a href="https://www.npmjs.com/package/datamaps">npm</a>'

    def query_obj(self):
        qry = super(WorldMapViz, self).query_obj()
        qry['metrics'] = [
            self.form_data['metric'], self.form_data['secondary_metric']]
        qry['groupby'] = [self.form_data['entity']]
        return qry

    def get_data(self, df):
        from superset.data import countries
        fd = self.form_data
        cols = [fd.get('entity')]
        metric = fd.get('metric')
        secondary_metric = fd.get('secondary_metric')
        if metric == secondary_metric:
            ndf = df[cols]
            # df[metric] will be a DataFrame
            # because there are duplicate column names
            ndf['m1'] = df[metric].iloc[:, 0]
            ndf['m2'] = ndf['m1']
        else:
            cols += [metric, secondary_metric]
            ndf = df[cols]
        df = ndf
        df.columns = ['country', 'm1', 'm2']
        d = df.to_dict(orient='records')
        for row in d:
            country = None
            if isinstance(row['country'], string_types):
                country = countries.get(
                    fd.get('country_fieldtype'), row['country'])

            if country:
                row['country'] = country['cca3']
                row['latitude'] = country['lat']
                row['longitude'] = country['lng']
                row['name'] = country['name']
            else:
                row['country'] = 'XXX'
        return d


class FilterBoxViz(BaseViz):

    """A multi filter, multi-choice filter box to make dashboards interactive"""

    viz_type = 'filter_box'
    verbose_name = _('Filters')
    is_timeseries = False
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'

    def query_obj(self):
        qry = super(FilterBoxViz, self).query_obj()
        groupby = self.form_data.get('groupby')
        if len(groupby) < 1 and not self.form_data.get('date_filter'):
            raise Exception(_('Pick at least one filter field'))
        qry['metrics'] = [
            self.form_data['metric']]
        return qry

    def get_data(self, df):
        qry = self.query_obj()
        filters = [g for g in self.form_data['groupby']]
        d = {}
        for flt in filters:
            qry['groupby'] = [flt]
            df = super(FilterBoxViz, self).get_df(qry)
            d[flt] = [{
                'id': row[0],
                'text': row[0],
                'filter': flt,
                'metric': row[1]}
                for row in df.itertuples(index=False)
            ]
        return d


class IFrameViz(BaseViz):

    """You can squeeze just about anything in this iFrame component"""

    viz_type = 'iframe'
    verbose_name = _('iFrame')
    credits = 'a <a href="https://github.com/airbnb/superset">Superset</a> original'
    is_timeseries = False

    def get_df(self):
        return None


class ParallelCoordinatesViz(BaseViz):

    """Interactive parallel coordinate implementation

    Uses this amazing javascript library
    https://github.com/syntagmatic/parallel-coordinates
    """

    viz_type = 'para'
    verbose_name = _('Parallel Coordinates')
    credits = (
        '<a href="https://syntagmatic.github.io/parallel-coordinates/">'
        "Syntagmatic's library</a>")
    is_timeseries = False

    def query_obj(self):
        d = super(ParallelCoordinatesViz, self).query_obj()
        fd = self.form_data
        d['metrics'] = copy.copy(fd.get('metrics'))
        second = fd.get('secondary_metric')
        if second not in d['metrics']:
            d['metrics'] += [second]
        d['groupby'] = [fd.get('series')]
        return d

    def get_data(self, df):
        return df.to_dict(orient='records')


class HeatmapViz(BaseViz):

    """A nice heatmap visualization that support high density through canvas"""

    viz_type = 'heatmap'
    verbose_name = _('Heatmap')
    is_timeseries = False
    credits = (
        'inspired from mbostock @<a href="http://bl.ocks.org/mbostock/3074470">'
        'bl.ocks.org</a>')

    def query_obj(self):
        d = super(HeatmapViz, self).query_obj()
        fd = self.form_data
        d['metrics'] = [fd.get('metric')]
        d['groupby'] = [fd.get('all_columns_x'), fd.get('all_columns_y')]
        return d

    def get_data(self, df):
        fd = self.form_data
        x = fd.get('all_columns_x')
        y = fd.get('all_columns_y')
        v = fd.get('metric')
        if x == y:
            df.columns = ['x', 'y', 'v']
        else:
            df = df[[x, y, v]]
            df.columns = ['x', 'y', 'v']
        norm = fd.get('normalize_across')
        overall = False
        max_ = df.v.max()
        min_ = df.v.min()
        bounds = fd.get('y_axis_bounds')
        if bounds and bounds[0] is not None:
            min_ = bounds[0]
        if bounds and bounds[1] is not None:
            max_ = bounds[1]
        if norm == 'heatmap':
            overall = True
        else:
            gb = df.groupby(norm, group_keys=False)
            if len(gb) <= 1:
                overall = True
            else:
                df['perc'] = (
                    gb.apply(
                        lambda x: (x.v - x.v.min()) / (x.v.max() - x.v.min()))
                )
        if overall:
            df['perc'] = (df.v - min_) / (max_ - min_)
        return {
            'records': df.to_dict(orient='records'),
            'extents': [min_, max_],
        }


class HorizonViz(NVD3TimeSeriesViz):

    """Horizon chart

    https://www.npmjs.com/package/d3-horizon-chart
    """

    viz_type = 'horizon'
    verbose_name = _('Horizon Charts')
    credits = (
        '<a href="https://www.npmjs.com/package/d3-horizon-chart">'
        'd3-horizon-chart</a>')


class MapboxViz(BaseViz):

    """Rich maps made with Mapbox"""

    viz_type = 'mapbox'
    verbose_name = _('Mapbox')
    is_timeseries = False
    credits = (
        '<a href=https://www.mapbox.com/mapbox-gl-js/api/>Mapbox GL JS</a>')

    def query_obj(self):
        d = super(MapboxViz, self).query_obj()
        fd = self.form_data
        label_col = fd.get('mapbox_label')

        if not fd.get('groupby'):
            d['columns'] = [fd.get('all_columns_x'), fd.get('all_columns_y')]

            if label_col and len(label_col) >= 1:
                if label_col[0] == 'count':
                    raise Exception(_(
                        "Must have a [Group By] column to have 'count' as the [Label]"))
                d['columns'].append(label_col[0])

            if fd.get('point_radius') != 'Auto':
                d['columns'].append(fd.get('point_radius'))

            d['columns'] = list(set(d['columns']))
        else:
            # Ensuring columns chosen are all in group by
            if (label_col and len(label_col) >= 1 and
                    label_col[0] != 'count' and
                    label_col[0] not in fd.get('groupby')):
                raise Exception(_(
                    'Choice of [Label] must be present in [Group By]'))

            if (fd.get('point_radius') != 'Auto' and
                    fd.get('point_radius') not in fd.get('groupby')):
                raise Exception(_(
                    'Choice of [Point Radius] must be present in [Group By]'))

            if (fd.get('all_columns_x') not in fd.get('groupby') or
                    fd.get('all_columns_y') not in fd.get('groupby')):
                raise Exception(_(
                    '[Longitude] and [Latitude] columns must be present in [Group By]'))
        return d

    def get_data(self, df):
        fd = self.form_data
        label_col = fd.get('mapbox_label')
        custom_metric = label_col and len(label_col) >= 1
        metric_col = [None] * len(df.index)
        if custom_metric:
            if label_col[0] == fd.get('all_columns_x'):
                metric_col = df[fd.get('all_columns_x')]
            elif label_col[0] == fd.get('all_columns_y'):
                metric_col = df[fd.get('all_columns_y')]
            else:
                metric_col = df[label_col[0]]
        point_radius_col = (
            [None] * len(df.index)
            if fd.get('point_radius') == 'Auto'
            else df[fd.get('point_radius')])

        # using geoJSON formatting
        geo_json = {
            'type': 'FeatureCollection',
            'features': [
                {
                    'type': 'Feature',
                    'properties': {
                        'metric': metric,
                        'radius': point_radius,
                    },
                    'geometry': {
                        'type': 'Point',
                        'coordinates': [lon, lat],
                    },
                }
                for lon, lat, metric, point_radius
                in zip(
                    df[fd.get('all_columns_x')],
                    df[fd.get('all_columns_y')],
                    metric_col, point_radius_col)
            ],
        }

        return {
            'geoJSON': geo_json,
            'customMetric': custom_metric,
            'mapboxApiKey': config.get('MAPBOX_API_KEY'),
            'mapStyle': fd.get('mapbox_style'),
            'aggregatorName': fd.get('pandas_aggfunc'),
            'clusteringRadius': fd.get('clustering_radius'),
            'pointRadiusUnit': fd.get('point_radius_unit'),
            'globalOpacity': fd.get('global_opacity'),
            'viewportLongitude': fd.get('viewport_longitude'),
            'viewportLatitude': fd.get('viewport_latitude'),
            'viewportZoom': fd.get('viewport_zoom'),
            'renderWhileDragging': fd.get('render_while_dragging'),
            'tooltip': fd.get('rich_tooltip'),
            'color': fd.get('mapbox_color'),
        }


class BaseDeckGLViz(BaseViz):

    """Base class for deck.gl visualizations"""

    is_timeseries = False
    credits = '<a href="https://uber.github.io/deck.gl/">deck.gl</a>'

    def get_metrics(self):
        self.metric = self.form_data.get('size')
        return [self.metric] if self.metric else []

    def get_properties(self, d):
        return {
            'weight': d.get(self.metric) or 1,
        }

    def get_position(self, d):
        return [
            d.get('lon'),
            d.get('lat'),
        ]

    def query_obj(self):
        d = super(BaseDeckGLViz, self).query_obj()
        fd = self.form_data

        gb = []

        spatial = fd.get('spatial')
        if spatial.get('type') == 'latlong':
            gb += [spatial.get('lonCol')]
            gb += [spatial.get('latCol')]
        elif spatial.get('type') == 'delimited':
            gb += [spatial.get('lonlatCol')]
        elif spatial.get('type') == 'geohash':
            gb += [spatial.get('geohashCol')]

        if fd.get('dimension'):
            gb += [fd.get('dimension')]

        metrics = self.get_metrics()
        if metrics:
            d['groupby'] = gb
            d['metrics'] = self.get_metrics()
        else:
            d['columns'] = gb
        return d

    def get_data(self, df):
        fd = self.form_data
        spatial = fd.get('spatial')
        if spatial.get('type') == 'latlong':
            df = df.rename(columns={
                spatial.get('lonCol'): 'lon',
                spatial.get('latCol'): 'lat'})
        elif spatial.get('type') == 'delimited':
            cols = ['lon', 'lat']
            if spatial.get('reverseCheckbox'):
                cols.reverse()
            df[cols] = (
                df[spatial.get('lonlatCol')]
                .str
                .split(spatial.get('delimiter'), expand=True)
                .astype(np.float64)
            )
            del df[spatial.get('lonlatCol')]
        elif spatial.get('type') == 'geohash':
            latlong = df[spatial.get('geohashCol')].map(geohash.decode)
            df['lat'] = latlong.apply(lambda x: x[0])
            df['lon'] = latlong.apply(lambda x: x[1])
            del df['geohash']

        features = []
        for d in df.to_dict(orient='records'):
            d = dict(position=self.get_position(d), **self.get_properties(d))
            features.append(d)
        return {
            'features': features,
            'mapboxApiKey': config.get('MAPBOX_API_KEY'),
        }


class DeckScatterViz(BaseDeckGLViz):

    """deck.gl's ScatterLayer"""

    viz_type = 'deck_scatter'
    verbose_name = _('Deck.gl - Scatter plot')

    def query_obj(self):
        fd = self.form_data
        self.point_radius_fixed = (
            fd.get('point_radius_fixed') or {'type': 'fix', 'value': 500})
        return super(DeckScatterViz, self).query_obj()

    def get_metrics(self):
        if self.point_radius_fixed.get('type') == 'metric':
            return [self.point_radius_fixed.get('value')]
        return None

    def get_properties(self, d):
        return {
            'radius': self.fixed_value if self.fixed_value else d.get(self.metric),
            'cat_color': d.get(self.dim) if self.dim else None,
        }

    def get_data(self, df):
        fd = self.form_data
        self.point_radius_fixed = fd.get('point_radius_fixed')
        self.fixed_value = None
        self.dim = self.form_data.get('dimension')
        if self.point_radius_fixed.get('type') != 'metric':
            self.fixed_value = self.point_radius_fixed.get('value')
        return super(DeckScatterViz, self).get_data(df)


class DeckScreengrid(BaseDeckGLViz):

    """deck.gl's ScreenGridLayer"""

    viz_type = 'deck_screengrid'
    verbose_name = _('Deck.gl - Screen Grid')


class DeckGrid(BaseDeckGLViz):

    """deck.gl's DeckLayer"""

    viz_type = 'deck_grid'
    verbose_name = _('Deck.gl - 3D Grid')


class DeckHex(BaseDeckGLViz):

    """deck.gl's DeckLayer"""

    viz_type = 'deck_hex'
    verbose_name = _('Deck.gl - 3D HEX')


class EventFlowViz(BaseViz):

    """A visualization to explore patterns in event sequences"""

    viz_type = 'event_flow'
    verbose_name = _('Event flow')
    credits = 'from <a href="https://github.com/williaster/data-ui">@data-ui</a>'
    is_timeseries = True

    def query_obj(self):
        query = super(EventFlowViz, self).query_obj()
        form_data = self.form_data

        event_key = form_data.get('all_columns_x')
        entity_key = form_data.get('entity')
        meta_keys = [
            col for col in form_data.get('all_columns')
            if col != event_key and col != entity_key
        ]

        query['columns'] = [event_key, entity_key] + meta_keys

        if form_data['order_by_entity']:
            query['orderby'] = [(entity_key, True)]

        return query

    def get_data(self, df):
        return df.to_dict(orient='records')


class PairedTTestViz(BaseViz):

    """A table displaying paired t-test values"""

    viz_type = 'paired_ttest'
    verbose_name = _('Time Series - Paired t-test')
    sort_series = False
    is_timeseries = True

    def get_data(self, df):
        """
        Transform received data frame into an object of the form:
        {
            'metric1': [
                {
                    groups: ('groupA', ... ),
                    values: [ {x, y}, ... ],
                }, ...
            ], ...
        }
        """
        fd = self.form_data
        groups = fd.get('groupby')
        metrics = fd.get('metrics')
        df.fillna(0)
        df = df.pivot_table(
            index=DTTM_ALIAS,
            columns=groups,
            values=metrics)
        cols = []
        # Be rid of falsey keys
        for col in df.columns:
            if col == '':
                cols.append('N/A')
            elif col is None:
                cols.append('NULL')
            else:
                cols.append(col)
        df.columns = cols
        data = {}
        series = df.to_dict('series')
        for nameSet in df.columns:
            # If no groups are defined, nameSet will be the metric name
            hasGroup = not isinstance(nameSet, string_types)
            Y = series[nameSet]
            d = {
                'group': nameSet[1:] if hasGroup else 'All',
                'values': [
                    {'x': t, 'y': Y[t] if t in Y else None}
                    for t in df.index
                ],
            }
            key = nameSet[0] if hasGroup else nameSet
            if key in data:
                data[key].append(d)
            else:
                data[key] = [d]
        return data


class PartitionViz(NVD3TimeSeriesViz):

    """
    A hierarchical data visualization with support for time series.
    """

    viz_type = 'partition'
    verbose_name = _('Partition Diagram')

    def query_obj(self):
        query_obj = super(PartitionViz, self).query_obj()
        time_op = self.form_data.get('time_series_option', 'not_time')
        # Return time series data if the user specifies so
        query_obj['is_timeseries'] = time_op != 'not_time'
        return query_obj

    def levels_for(self, time_op, groups, df):
        """
        Compute the partition at each `level` from the dataframe.
        """
        levels = {}
        for i in range(0, len(groups) + 1):
            agg_df = df.groupby(groups[:i]) if i else df
            levels[i] = (
                agg_df.mean() if time_op == 'agg_mean'
                else agg_df.sum(numeric_only=True))
        return levels

    def levels_for_diff(self, time_op, groups, df):
        # Obtain a unique list of the time grains
        times = list(set(df[DTTM_ALIAS]))
        times.sort()
        until = times[len(times) - 1]
        since = times[0]
        # Function describing how to calculate the difference
        func = {
            'point_diff': [
                pd.Series.sub,
                lambda a, b, fill_value: a - b,
            ],
            'point_factor': [
                pd.Series.div,
                lambda a, b, fill_value: a / float(b),
            ],
            'point_percent': [
                lambda a, b, fill_value=0: a.div(b, fill_value=fill_value) - 1,
                lambda a, b, fill_value: a / float(b) - 1,
            ],
        }[time_op]
        agg_df = df.groupby(DTTM_ALIAS).sum()
        levels = {0: pd.Series({
            m: func[1](agg_df[m][until], agg_df[m][since], 0)
            for m in agg_df.columns})}
        for i in range(1, len(groups) + 1):
            agg_df = df.groupby([DTTM_ALIAS] + groups[:i]).sum()
            levels[i] = pd.DataFrame({
                m: func[0](agg_df[m][until], agg_df[m][since], fill_value=0)
                for m in agg_df.columns})
        return levels

    def levels_for_time(self, groups, df):
        procs = {}
        for i in range(0, len(groups) + 1):
            self.form_data['groupby'] = groups[:i]
            df_drop = df.drop(groups[i:], 1)
            procs[i] = self.process_data(df_drop, aggregate=True).fillna(0)
        self.form_data['groupby'] = groups
        return procs

    def nest_values(self, levels, level=0, metric=None, dims=()):
        """
        Nest values at each level on the back-end with
        access and setting, instead of summing from the bottom.
        """
        if not level:
            return [{
                'name': m,
                'val': levels[0][m],
                'children': self.nest_values(levels, 1, m),
            } for m in levels[0].index]
        if level == 1:
            return [{
                'name': i,
                'val': levels[1][metric][i],
                'children': self.nest_values(levels, 2, metric, (i,)),
            } for i in levels[1][metric].index]
        if level >= len(levels):
            return []
        return [{
            'name': i,
            'val': levels[level][metric][dims][i],
            'children': self.nest_values(
                levels, level + 1, metric, dims + (i,),
            ),
        } for i in levels[level][metric][dims].index]

    def nest_procs(self, procs, level=-1, dims=(), time=None):
        if level == -1:
            return [{
                'name': m,
                'children': self.nest_procs(procs, 0, (m,)),
            } for m in procs[0].columns]
        if not level:
            return [{
                'name': t,
                'val': procs[0][dims[0]][t],
                'children': self.nest_procs(procs, 1, dims, t),
            } for t in procs[0].index]
        if level >= len(procs):
            return []
        return [{
            'name': i,
            'val': procs[level][dims][i][time],
            'children': self.nest_procs(procs, level + 1, dims + (i,), time),
        } for i in procs[level][dims].columns]

    def get_data(self, df):
        fd = self.form_data
        groups = fd.get('groupby', [])
        time_op = fd.get('time_series_option', 'not_time')
        if not len(groups):
            raise ValueError('Please choose at least one groupby')
        if time_op == 'not_time':
            levels = self.levels_for('agg_sum', groups, df)
        elif time_op in ['agg_sum', 'agg_mean']:
            levels = self.levels_for(time_op, groups, df)
        elif time_op in ['point_diff', 'point_factor', 'point_percent']:
            levels = self.levels_for_diff(time_op, groups, df)
        elif time_op == 'adv_anal':
            procs = self.levels_for_time(groups, df)
            return self.nest_procs(procs)
        else:
            levels = self.levels_for('agg_sum', [DTTM_ALIAS] + groups, df)
        return self.nest_values(levels)


viz_types = {
    o.viz_type: o for o in globals().values()
    if (
        inspect.isclass(o) and
        issubclass(o, BaseViz) and
        o.viz_type not in config.get('VIZ_TYPE_BLACKLIST'))}