Merge pull request #3 from thejunglejane/feature/column-metadata-data…

…-types

Feature/column metadata data types

README.md

@@ -51,7 +51,7 @@ This variable will not be available in later sessions.
 
 pynigma uses `unittest`. To run the tests
 ```bash
-$ python -m unittest discovery tests/
+$ python -m unittest discover tests/
 ```
 
 # Usage
@@ -121,6 +121,8 @@ for column in metadata['result']['columns']:
     print column['label']
 ```
 
+The column metadata returned by pynigma will include an additional key not returned by the endpoint, 'python_type', representing the Python data type that corresponds to the type string returned. Mappings are based on the [PL/Python PostgreSQL to Python mappings](http://www.postgresql.org/docs/9.4/static/plpython-data.html). If pynigma cannot determine the Python data type using these mappings, it will default to `str`, which is consistent with PL/Python.
+
 ### Stats Endpoint
 
 The [stats endpoint](https://app.enigma.io/api#stats) provides statistics on columns within table datapaths. The stats endpoint is accessed via the `get_stats()` method.

pynigma/__init__.py

@@ -1,2 +1,2 @@
 __all__ = ['client']
-__version__ = '0.0.1'
+__version__ = '0.0.2'

pynigma/client.py

@@ -1,10 +1,35 @@
+from datetime import date, datetime
+import decimal
 import requests
 import warnings
 
 API_ENDPOINT = 'https://api.enigma.io'
 API_VERSION = 'v2'
 
 
+# Data type mappings are based on PL/Python PostgreSQL to Python mappings
+# http://www.postgresql.org/docs/9.4/static/plpython-data.html
+_data_type_mapping = {
+    'bigint': long,
+    'boolean': bool,
+    'bytea': str,
+    'character varying': str,
+    'date': date,
+    'double': float,
+    'double precision': float,
+    'int': int,
+    'integer': int,
+    'numeric': decimal.Decimal,
+    'oid': long,
+    'real': float,
+    'smallint': int,
+    'text': str,
+    'timestamp without time zone': datetime,
+    'timestamp': datetime,
+    'varcahr': str
+}
+
+
 class EnigmaAPI(object):
 
     '''The EnigmaAPI provides access to the five different endpoints of the
@@ -96,6 +121,9 @@ def get_data(self, datapath, **kwargs):
 
     def get_metadata(self, datapath, **kwargs):
         '''Returns an HTTP response from the metadata endpoint as decoded JSON.
+        The column metadata will include an additional key, 'python_type',
+        representing the corresponding Python data type. If the Python data
+        type can't be determined, it will default to str.
 
         ARGUMENTS
         ---------
@@ -115,7 +143,13 @@ def get_metadata(self, datapath, **kwargs):
         Full Name
         Appointment Number
         '''
-        return self._request(resource='meta', datapath=datapath, **kwargs)
+        metadata_res =  self._request(
+            resource='meta', datapath=datapath, **kwargs)
+        # Map returned type strings to Python data types
+        for column in metadata_res['result']['columns']:
+            column['python_type'] = _data_type_mapping.get(
+                column['type'].split('_')[1], str)
+        return metadata_res
 
     def get_stats(self, datapath, **kwargs):
         '''Returns an HTTP response from the stats endpoint as decoded JSON.

setup.py

@@ -17,5 +17,5 @@ def readme():
     author_email = '[email protected]',
     license = 'MIT',
     url = 'https://github.com/thejunglejane/pynigma',
-    download_url = 'https://github.com/thejunglejane/pynigma/tarball/0.0.1'
+    download_url = 'https://github.com/thejunglejane/pynigma/tarball/0.0.2'
 )

tests/test_client.py

@@ -1,4 +1,5 @@
 from pynigma import client
+import decimal
 import unittest
 import os
 
@@ -102,6 +103,24 @@ def test_get_metadata_no_datapath_failure(self):
         with self.assertRaises(TypeError):
             self.new_client.get_metadata()
 
+    def test_get_metadata_python_data_type(self):
+        '''Does get_metadata() return a dictionary key corresponding to the
+        Python data type of a column?
+        '''
+        metadata = self.new_client.get_metadata(
+            datapath='us.gov.whitehouse.visitor-list')
+        self.assertIsNotNone(
+            metadata['result']['columns'][0].get('python_type'))
+
+    def test_get_metadata_correct_python_data_type(self):
+        '''Does get_metadata() return the correct Python data type for the type
+        string returned?
+        '''
+        metadata = self.new_client.get_metadata(
+            datapath='us.gov.whitehouse.salaries.2011')
+        self.assertEquals(
+            metadata['result']['columns'][2]['python_type'], decimal.Decimal)
+
     def test_get_stats_no_datapath_failure(self):
         '''Does get_stats() raise a TypeError when no datapath is passed?
         '''