ENH: Add support for AlphaVantage API (#490)

* Added AlphaVantage readeres

* DOCS: Cleanup AlphaVantage docs

* Added AlphaVantage Quotes Reader

* Updated AV tests

* Updated AV docstrings, repaired names

* DOCS: Added Alphavantage to readers index

docs/source/readers/alphavantage.rst

@@ -0,0 +1,29 @@
+AlphaVantage
+------------
+
+.. py:module:: pandas_datareader.av.forex
+
+.. autoclass:: AVForexReader
+   :members:
+   :inherited-members:
+
+
+.. py:module:: pandas_datareader.av.time_series
+
+.. autoclass:: AVTimeSeriesReader
+	:members:
+	:inherited-members:
+
+
+.. py:module:: pandas_datareader.av.sector
+
+.. autoclass:: AVSectorPerformanceReader
+	:members:
+	:inherited-members:
+
+
+.. py:module:: pandas_datareader.av.quotes
+
+.. autoclass:: AVQuotesReader
+	:members:
+	:inherited-members:

docs/source/readers/index.rst

@@ -4,6 +4,7 @@ Data Readers
 .. toctree::
    :maxdepth: 2
 
+   alphavantage
    fred
    famafrench
    bank-of-canada

docs/source/remote_data.rst

@@ -33,6 +33,7 @@ Currently the following sources are supported:
     - :ref:`Morningstar<remote_data.morningstar>`
     - :ref:`IEX<remote_data.iex>`
     - :ref:`Robinhood<remote_data.robinhood>`
+    - :ref:`AlphaVantage<remote_data.alphavantage>`
     - :ref:`Enigma<remote_data.enigma>`
     - :ref:`Quandl<remote_data.quandl>`
     - :ref:`St.Louis FED (FRED)<remote_data.fred>`
@@ -146,6 +147,107 @@ year relative to today.
     f = web.DataReader('F', 'robinhood')
     f.head()
 
+
+.. _remote_data.alphavantage
+
+AlphaVantage
+============
+
+`AlphaVantage <https://www.alphavantage.co/documentation>`__ provides realtime
+equities and forex data. Free registration is required to get an API key. 
+
+Historical Time Series Data
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Through the 
+`AlphaVantage <https://www.alphavantage.co/documentation>`__ Time Series
+endpoints, it is possible to obtain historical equities data for individual
+symbols. The following endpoints are available:
+
+* ``av-daily`` - Daily Time Series
+* ``av-daily-adjusted`` - Daily Time Series (Adjusted)
+* ``av-weekly`` - Weekly Time Series
+* ``av-weekly-adjusted`` - Weekly Time Series (Adjusted)
+* ``av-monthly`` - Monthly Time Series
+* ``av-monthly-adjusted`` - Monthly Time Series (Adjusted)
+
+.. ipython:: python
+
+    import os
+    from datetime import datetime
+    import pandas_datareader.data as web
+
+    f = web.DataReader("AAPL", "av-daily", start=datetime(2017, 2, 9),
+                       end=datetime(2017, 5, 24),
+                       access_key=os.getenv('ALPHAVANTAGE_API_KEY'))
+    f.loc["2017-02-09"]
+
+The top-level function ``get_data_alphavantage`` is also provided. This
+function will
+return the ``TIME_SERIES_DAILY`` endpoint for the symbol and date range
+provided.
+
+Quotes
+^^^^^^
+
+`AlphaVantage <https://www.alphavantage.co/documentation>`__ Batch Stock Quotes
+endpoint allows the retrieval of realtime stock quotes for up to 100 symbols at
+once. These quotes are accessible through the top-level function
+``get_quote_av``.
+
+.. ipython:: python
+
+    import os
+    from datetime import datetime
+    import pandas_datareader.data as web
+
+    web.get_quote_av(["AAPL", "TSLA"])
+
+
+.. note:: Most quotes are only available during market hours.
+
+Forex
+^^^^^
+
+`AlphaVantage <https://www.alphavantage.co/documentation>`__ provides realtime
+currency exchange rates (for physical and digital currencies). 
+
+To request the exchange rate of physical or digital currencies, simply format
+as "FROM/TO" as in "USD/JPY".
+
+.. ipython:: python
+
+    import os
+    import pandas_datareader.data as web
+
+    f = web.DataReader("USD/JPY", "av-forex", 
+                       access_key=os.getenv('ALPHAVANTAGE_API_KEY'))
+
+Multiple pairs are are allowable:
+
+.. ipython:: python
+
+    import os
+    import pandas_datareader.data as web
+
+    f = web.DataReader(["USD/JPY", "BTC/CNY"], "av-forex",
+                       access_key=os.getenv('ALPHAVANTAGE_API_KEY'))
+
+
+Sector Performance
+^^^^^^^^^^^^^^^^^^
+
+`AlphaVantage <https://www.alphavantage.co/documentation>`__ provides sector
+performances through the top-level function ``get_sector_performance_av``.
+
+.. ipython:: python
+
+    import os
+    import pandas_datareader.data as web
+
+    web.get_sector_performance_av().head()
+
+
 .. _remote_data.enigma:
 
 Enigma

docs/source/whatsnew/v0.7.0.txt

@@ -16,6 +16,28 @@ Highlights include:
 Enhancements
 ~~~~~~~~~~~~
 
+- A new data connector for data provided by
+  `AlphaVantage <https://www.alphavantage.co/documentation>`__ was
+  introduced to obtain Foreign Exchange (FX) data.
+  (:issue:`389`)
+
+- A new data connector for data provided by
+  `AlphaVantage <https://www.alphavantage.co/documentation>`__ was
+  introduced to obtain historical time series data.
+  (:issue:`389`)
+
+  - A new data connector for data provided by
+  `AlphaVantage <https://www.alphavantage.co/documentation>`__ was
+  introduced to obtain sector performance data, accessed through the
+  top-level function ``get_sector_performance_av``.
+  (:issue:`389`)
+
+  - A new data connector for data provided by
+  `AlphaVantage <https://www.alphavantage.co/documentation>`__ was
+  introduced to obtain real-time Batch Stock Quotes through the
+  top-level function ``get_quote_av``.
+  (:issue:`389`)
+
 .. _whatsnew_070.api_breaking:
 
 Backwards incompatible API changes

pandas_datareader/av/__init__.py

@@ -0,0 +1,66 @@
+import os
+
+from pandas_datareader.base import _BaseReader
+from pandas_datareader._utils import RemoteDataError
+
+import pandas as pd
+
+AV_BASE_URL = 'https://www.alphavantage.co/query'
+
+
+class AlphaVantage(_BaseReader):
+    """
+    Base class for all AlphaVantage queries
+    """
+    _format = 'json'
+
+    def __init__(self, symbols=None, start=None, end=None, retry_count=3,
+                 pause=0.001, session=None, api_key=None):
+        super(AlphaVantage, self).__init__(symbols=symbols, start=start,
+                                           end=end, retry_count=retry_count,
+                                           pause=pause, session=session)
+        if api_key is None:
+            api_key = os.getenv('ALPHAVANTAGE_API_KEY')
+        if not api_key or not isinstance(api_key, str):
+            raise ValueError('The AlphaVantage API key must be provided '
+                             'either through the api_key variable or '
+                             'through the environment varaible '
+                             'ALPHAVANTAGE_API_KEY')
+        self.api_key = api_key
+
+    @property
+    def url(self):
+        """ API URL """
+        return AV_BASE_URL
+
+    @property
+    def params(self):
+        return {
+            'function': self.function,
+            'apikey': self.api_key
+        }
+
+    @property
+    def function(self):
+        """ AlphaVantage endpoint function"""
+        raise NotImplementedError
+
+    @property
+    def data_key(self):
+        """ Key of data returned from AlphaVantage """
+        raise NotImplementedError
+
+    def _read_lines(self, out):
+        try:
+            df = pd.DataFrame.from_dict(out[self.data_key], orient='index')
+        except KeyError:
+            if "Error Message" in out:
+                raise ValueError("The requested symbol {} could not be "
+                                 "retrived. Check valid ticker"
+                                 ".".format(self.symbols))
+            else:
+                raise RemoteDataError()
+        df = df[sorted(df.columns)]
+        # df.sort_index(ascending=True, inplace=True)
+        df.columns = [id[3:] for id in df.columns]
+        return df

pandas_datareader/av/forex.py

@@ -0,0 +1,93 @@
+from pandas_datareader.av import AlphaVantage
+
+from pandas_datareader._utils import RemoteDataError
+
+import pandas as pd
+
+
+class AVForexReader(AlphaVantage):
+    """
+    Returns DataFrame of the AlphaVantage Foreign Exchange (FX) Exchange Rates
+    data.
+
+    .. versionadded:: 0.7.0
+
+    Parameters
+    ----------
+    symbols : string, array-like object (list, tuple, Series)
+        Single currency pair (formatted 'FROM/TO') or list of the same.
+    retry_count : int, default 3
+        Number of times to retry query request.
+    pause : int, default 0.5
+        Time, in seconds, to pause between consecutive queries of chunks. If
+        single value given for symbol, represents the pause between retries.
+    session : Session, default None
+        requests.sessions.Session instance to be used
+    api_key : str, optional
+        AlphaVantage API key . If not provided the environmental variable
+        ALPHAVANTAGE_API_KEY is read. The API key is *required*.
+    """
+    def __init__(self, symbols=None, retry_count=3, pause=0.5, session=None,
+                 api_key=None):
+
+        super(AVForexReader, self).__init__(symbols=symbols,
+                                            start=None, end=None,
+                                            retry_count=retry_count,
+                                            pause=pause,
+                                            session=session,
+                                            api_key=api_key)
+        self.from_curr = {}
+        self.to_curr = {}
+        self.optional_params = {}
+        if isinstance(symbols, str):
+            self.symbols = [symbols]
+        else:
+            self.symbols = symbols
+        try:
+            for pair in self.symbols:
+                self.from_curr[pair] = pair.split('/')[0]
+                self.to_curr[pair] = pair.split('/')[1]
+        except Exception as e:
+            print(e)
+            raise ValueError("Please input a currency pair "
+                             "formatted 'FROM/TO' or a list of "
+                             "currency symbols")
+
+    @property
+    def function(self):
+        return 'CURRENCY_EXCHANGE_RATE'
+
+    @property
+    def data_key(self):
+        return 'Realtime Currency Exchange Rate'
+
+    @property
+    def params(self):
+        params = {
+            'apikey': self.api_key,
+            'function': self.function
+            }
+        params.update(self.optional_params)
+        return params
+
+    def read(self):
+        result = []
+        for pair in self.symbols:
+            self.optional_params = {
+                'from_currency': self.from_curr[pair],
+                'to_currency': self.to_curr[pair],
+                }
+            data = super(AVForexReader, self).read()
+            result.append(data)
+        df = pd.concat(result, axis=1)
+        df.columns = self.symbols
+        return df
+
+    def _read_lines(self, out):
+        try:
+            df = pd.DataFrame.from_dict(out[self.data_key], orient='index')
+        except KeyError:
+            raise RemoteDataError()
+        df.sort_index(ascending=True, inplace=True)
+        df.index = [id[3:] for id in df.index]
+        return df