support filter function against ES version >= 5.0

Author: onesuper

CHANGELOG.md

@@ -1,5 +1,6 @@
 ### 0.4.0
 
+* support filter function against ES version >= 5.0
 * support customized terms aggregation: `df.groupby(df.age.terms(limit=10, include=[1, 2, 3]))`
 
 ### 0.3.0

README.md

@@ -106,6 +106,13 @@ df.filter(ScriptFilter('2016 - doc["age"].value > 1995')).collect()
 # [Row(age=12,name='Alice'), Row(age=13,name='Leo')]
 ```
 
+**5.0 compatibility**: By default, pandasticsearch use `filtered` query (deprecated since 5.0). 
+To use pandasticsearch against the latest ES version, a `compat` arg can be passed to `from_es`:
+
+```
+df = DataFrame.from_es(url='http://localhost:9200', index='people', compat=5)
+```
+
 
 ### Aggregation
 ```python

pandasticsearch/dataframe.py

@@ -38,13 +38,13 @@ def __init__(self, **kwargs):
         self._index = list(self._mapping.keys())[0] if self._mapping else None
         self._doc_type = DataFrame._get_doc_type(self._mapping) if self._mapping else None
         self._columns = sorted(DataFrame._get_cols(self._mapping)) if self._mapping else None
-
         self._filter = kwargs.get('filter', None)
         self._groupby = kwargs.get('groupby', None)
         self._aggregation = kwargs.get('aggregation', None)
         self._sort = kwargs.get('sort', None)
         self._projection = kwargs.get('projection', None)
         self._limit = kwargs.get('limit', None)
+        self._compat = kwargs.get('compat', 2)
         self._last_query = None
 
     @property
@@ -448,7 +448,10 @@ def _build_query(self):
                 query['size'] = 0
 
         if self._filter:
-            query['query'] = {'filtered': {'filter': self._filter}}
+            if self._compat == 5:
+                query['query'] = {'bool': {'filter': self._filter}}
+            else:
+                query['query'] = {'filtered': {'filter': self._filter}}
 
         if self._projection:
             query['_source'] = {"includes": [col.field_name() for col in self._projection], "excludes": []}