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

import copy
import hashlib
import logging
import traceback
import uuid
import zlib

from collections import OrderedDict, defaultdict
from datetime import datetime, timedelta

import pandas as pd
import numpy as np
from flask import request
from flask_babel import lazy_gettext as _
from markdown import markdown
import simplejson as json
from six import string_types, PY3
from dateutil import relativedelta as rdelta

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

config = app.config


class BaseViz(object):

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

    viz_type = None
    verbose_name = "Base Viz"
    credits = ""
    is_timeseries = False

    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.status = None
        self.error_message = None

    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)
            df = df.fillna(0)
        return df

    def get_extra_filters(self):
        extra_filters = self.form_data.get('extra_filters', [])
        return {f['col']: f['val'] for f in extra_filters}

    def query_obj(self):
        """Building a query object"""
        form_data = self.form_data
        groupby = form_data.get("groupby") or []
        metrics = form_data.get("metrics") or []

        # extra_filters are temporary/contextual filters that are external
        # to the slice definition. We use those for dynamic interactive
        # filters like the ones emitted by the "Filter Box" visualization
        extra_filters = self.get_extra_filters()
        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"))

        # __form and __to are special extra_filters that target time
        # boundaries. The rest of extra_filters are simple
        # [column_name in list_of_values]. `__` prefix is there to avoid
        # potential conflicts with column that would be named `from` or `to`
        since = (
            extra_filters.get('__from') or form_data.get("since", "1 year ago")
        )

        from_dttm = utils.parse_human_datetime(since)
        now = datetime.now()
        if from_dttm > now:
            from_dttm = now - (from_dttm - now)

        until = extra_filters.get('__to') or form_data.get("until", "now")
        to_dttm = utils.parse_human_datetime(until)
        if from_dttm > to_dttm:
            raise Exception("From date cannot be larger than to date")

        # 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') \
                if 'having_filters' in form_data else [],
            'time_grain_sqla': form_data.get("time_grain_sqla", ''),
            'druid_time_origin': form_data.get("druid_time_origin", ''),
        }
        filters = form_data['filters'] if 'filters' in form_data \
                else []
        for col, vals in self.get_extra_filters().items():
            if not (col and vals) or col.startswith('__'):
                continue
            elif col in self.datasource.filterable_column_names:
                # Quote values with comma to avoid conflict
                filters += [{
                    'col': col,
                    'op': 'in',
                    'val': vals,
                }]
        d = {
            'granularity': granularity,
            'from_dttm': from_dttm,
            'to_dttm': to_dttm,
            'is_timeseries': self.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,
        }
        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):
        s = str([(k, self.form_data[k]) for k in sorted(self.form_data.keys())])
        return hashlib.md5(s.encode('utf-8')).hexdigest()

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

        if payload:
            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
            logging.info("Serving from cache")

        if not payload:
            data = None
            is_cached = False
            cache_timeout = self.cache_timeout
            stacktrace = None
            try:
                df = self.get_df()
                if not self.error_message:
                    data = self.get_data(df)
            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,
            }
            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, encoding="utf-8")

    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")

        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]

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

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

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

    def json_dumps(self, obj):
        return json.dumps(obj, default=utils.json_iso_dttm_ser)


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("groupby and columns can't overlap")

        d['groupby'] = list(set(groupby) | set(columns))
        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=True,
        )
        return 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)


class SeparatorViz(MarkupViz):

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

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

    def get_data(self, df):
        code = markdown(self.form_data.get("code", ''))
        return dict(html=code)


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'] = list({
            form_data.get('series'),
            form_data.get('entity')
        })
        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')

        d['metrics'] = [
            self.z_metric,
            self.x_metric,
            self.y_metric,
        ]
        if not all(d['metrics'] + [self.entity, self.series]):
            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
            if isinstance(name, string_types):
                series_title = name
            else:
                name = ["{}".format(s) for s in name]
                if len(self.form_data.get('metrics')) > 1:
                    series_title = ", ".join(name)
                else:
                    series_title = ", ".join(name[1:])
            if title_suffix:
                series_title += title_suffix

            d = {
                "key": series_title,
                "classed": classed,
                "values": [
                    {'x': ds, 'y': ys[ds] if ds in ys else None}
                    for ds in df.index
                ],
            }
            chart_data.append(d)
        return chart_data

    def get_data(self, df):
        fd = self.form_data
        df = df.fillna(0)
        if fd.get("granularity") == "all":
            raise Exception("Pick a time granularity for your time series")

        df = df.pivot_table(
            index=DTTM_ALIAS,
            columns=fd.get('groupby'),
            values=fd.get('metrics'))

        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_periods = fd.get("rolling_periods")
        rolling_type = fd.get("rolling_type")

        if rolling_type in ('mean', 'std', 'sum') and rolling_periods:
            if rolling_type == 'mean':
                df = pd.rolling_mean(df, int(rolling_periods), min_periods=0)
            elif rolling_type == 'std':
                df = pd.rolling_std(df, int(rolling_periods), min_periods=0)
            elif rolling_type == 'sum':
                df = pd.rolling_sum(df, int(rolling_periods), min_periods=0)
        elif rolling_type == 'cumsum':
            df = df.cumsum()

        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:]

        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 = df2.pivot_table(
                index=DTTM_ALIAS,
                columns=fd.get('groupby'),
                values=fd.get('metrics'))
            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 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
        gb = fd.get('groupby') or []
        cols = fd.get('columns') or []
        d['groupby'] = set(gb + cols)
        if len(d['groupby']) < len(gb) + len(cols):
            raise Exception("Can't have overlap between Series and Breakdowns")
        if not self.metrics:
            raise Exception("Pick at least one metric")
        if not self.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:]]
                series_title = ", ".join(l)
            values = []
            for i, v in ys.iteritems():
                x = i
                if isinstance(x, (tuple, list)):
                    x = ', '.join([str(s) for s in x])
                else:
                    x = str(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 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
        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:
            v = df.v
            min_ = v.min()
            df['perc'] = (v - min_) / (v.max() - min_)
        return df.to_dict(orient="records")


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"),
        }


viz_types_list = [
    TableViz,
    PivotTableViz,
    NVD3TimeSeriesViz,
    NVD3DualLineViz,
    NVD3CompareTimeSeriesViz,
    NVD3TimeSeriesStackedViz,
    NVD3TimeSeriesBarViz,
    DistributionBarViz,
    DistributionPieViz,
    BubbleViz,
    BulletViz,
    MarkupViz,
    WordCloudViz,
    BigNumberViz,
    BigNumberTotalViz,
    SunburstViz,
    DirectedForceViz,
    SankeyViz,
    WorldMapViz,
    FilterBoxViz,
    IFrameViz,
    ParallelCoordinatesViz,
    HeatmapViz,
    BoxPlotViz,
    TreemapViz,
    CalHeatmapViz,
    HorizonViz,
    MapboxViz,
    HistogramViz,
    SeparatorViz,
]

viz_types = OrderedDict([(v.viz_type, v) for v in viz_types_list
                         if v.viz_type not in config.get('VIZ_TYPE_BLACKLIST')])