#4 Adds codecov

.gitignore

@@ -3,3 +3,4 @@
 __pycache__
 build
 dist
+.coverage

docs/EXAMPLES.md

@@ -115,10 +115,10 @@ python3 examples/sqlite_display_filter.py data/example.sqlite
 ```
 ```
 > tables
-People
+Actors
 ```
 ```
-> use People
+> use Actors
 Database changed
 ```
 ```

examples/csv_display_filter.py

@@ -51,7 +51,12 @@ def read_csv_file(csv_file):
 
     try:
         data_store = read_csv_file(csv_file)
-        DictDisplayFilterShell(data_store).cmdloop()
+        if not data_store or len(data_store) == 0:
+            field_names = list()
+        else:
+            # Extract field names from header.
+            field_names = list(data_store[0].keys())
+        DictDisplayFilterShell(data_store, field_names=field_names).cmdloop()
     except Exception as err:
         logger.error(str(err))
         traceback.print_exc()

examples/json_display_filter.py

@@ -20,10 +20,12 @@
 import os.path
 import sys
 import traceback
-from typing import List, Set
+from typing import List, Set, Dict, Callable
 
 from pydictdisplayfilter import DictDisplayFilter
+from pydictdisplayfilter.evaluators import Evaluator
 from pydictdisplayfilter.helpers import Table, DisplayFilterShell
+from pydictdisplayfilter.slicers import BasicSlicer
 
 
 def read_json_file(json_file):
@@ -38,18 +40,24 @@ def read_json_file(json_file):
 class JSONTable(Table):
     """ Data store with filter capabilities and pretty table printout. """
 
-    def __init__(self, data_store: List[dict]):
+    def __init__(self,
+                 data_store: List[dict],
+                 field_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
         """ Initializes the DictTable with a data store. """
         self._data_store = data_store
-        super().__init__(DictDisplayFilter(data_store))
+        super().__init__(DictDisplayFilter(data_store, field_names, functions, slicers, evaluator))
 
     def _make_table(self, data_store: List[dict]) -> List[str]:
         """ Creates a view for nested data items. """
         return [json.dumps(data) for data in data_store]
 
     def _extract_keys(self, data_store: List[dict]) -> List[str]:
         """ Extracts the keys from a nested data store. """
-        def extract_keys(data: dict, parent_key: str='') -> Set[str]:
+
+        def extract_keys(data: dict, parent_key: str = '') -> Set[str]:
             keys = set()
             if isinstance(data, dict):
                 for k, v in data.items():
@@ -62,7 +70,7 @@ def extract_keys(data: dict, parent_key: str='') -> Set[str]:
         all_keys = set()
         for data in data_store:
             all_keys |= extract_keys(data)
-        return list(all_keys)
+        return list(sorted(all_keys))
 
     def fields(self, thorough: bool = True) -> List[str]:
         """ Returns the field names used in the data store. """
@@ -75,9 +83,20 @@ def fields(self, thorough: bool = True) -> List[str]:
 class JSONDisplayFilterShell(DisplayFilterShell):
     """ A little shell for querying a list of dictionaries using the display filter. """
 
-    def __init__(self, data_store: List[dict]):
+    def __init__(self,
+                 data_store: List[dict],
+                 field_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
         """ Initializes the DictDisplayFilterShell with a data store. """
-        super().__init__(JSONTable(data_store))
+        super().__init__(
+            JSONTable(
+                data_store=data_store,
+                field_names=field_names,
+                functions=functions,
+                slicers=slicers,
+                evaluator=evaluator))
 
 
 if __name__ == '__main__':

examples/nmap_display_filter.py

@@ -89,7 +89,7 @@ def parse(self, nmap_xml_file) -> List[dict]:
 
     try:
         data_store = NmapXMLParser().parse(nmap_xml_file)
-        DictDisplayFilterShell(data_store).cmdloop()
+        DictDisplayFilterShell(data_store, field_names=["host", "port", "protocol", "status", "service"]).cmdloop()
     except Exception as err:
         logger.error(str(err))
         traceback.print_exc()

examples/sqlite_display_filter.py

@@ -20,10 +20,12 @@
 import sqlite3
 import sys
 import traceback
-from typing import List
+from typing import List, Dict, Callable
 
 from pydictdisplayfilter.display_filters import SQLDisplayFilter
+from pydictdisplayfilter.evaluators import Evaluator
 from pydictdisplayfilter.helpers import DisplayFilterShell, Table, TableError
+from pydictdisplayfilter.slicers import BasicSlicer
 
 
 class TableNotFoundError(TableError):
@@ -41,10 +43,23 @@ def __init__(self):
 class SQLiteTable(Table):
     """ Data store with filter capabilities and pretty table printout. """
 
-    def __init__(self, database_file: str):
+    def __init__(self,
+                 database_file: str,
+                 table_name: str = None,
+                 column_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
         self._database_file = database_file
         self._connection = sqlite3.connect(database_file)
-        super().__init__(SQLDisplayFilter(self._connection))
+        super().__init__(
+            SQLDisplayFilter(
+                connection=self._connection,
+                table_name=table_name,
+                column_names=column_names,
+                functions=functions,
+                slicers=slicers,
+                evaluator=evaluator))
 
     def _table_exists(self, table_name: str) -> bool:
         """ Checks whether the specified table does exist. """
@@ -101,9 +116,22 @@ def filter(self, display_filter: str) -> str:
 class SQLiteDisplayFilterShell(DisplayFilterShell):
     """ A little shell for querying a SQLite database using the display filter. """
 
-    def __init__(self, database_file: str):
+    def __init__(self,
+                 database_file: str,
+                 table_name: str = None,
+                 column_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
         """ Initializes the SQLiteDisplayFilterShell with a database file. """
-        super().__init__(SQLiteTable(database_file=database_file))
+        super().__init__(
+            SQLiteTable(
+                database_file=database_file,
+                table_name=table_name,
+                column_names=column_names,
+                functions=functions,
+                slicers=slicers,
+                evaluator=evaluator))
 
     def do_tables(self, *args):
         """ Returns all tables which can be selected. """

pydictdisplayfilter/display_filters.py

@@ -52,9 +52,9 @@ def __init__(self,
         }
         self._slicer_factory = SlicerFactory(slicers)
         self._evaluator = evaluator if evaluator else DefaultEvaluator()
-        self._functions = functions
-        self._field_names = field_names
-        self._display_filter_parser = DisplayFilterParser(field_names, functions)
+        self._functions = functions or []
+        self._field_names = field_names or []
+        self._display_filter_parser = DisplayFilterParser(field_names=field_names, functions=functions)
 
     def _get_item_value(self, expression, item) -> str:
         """
@@ -103,7 +103,7 @@ def field_names(self) -> List[str]:
     @field_names.setter
     def field_names(self, field_names: List[str] = None):
         self._field_names = field_names
-        self._display_filter_parser = DisplayFilterParser(self._field_names, self._functions)
+        self._display_filter_parser = DisplayFilterParser(field_names=self._field_names, functions=self._functions)
 
     @property
     def functions(self) -> Dict[str, Callable]:
@@ -112,7 +112,7 @@ def functions(self) -> Dict[str, Callable]:
     @functions.setter
     def functions(self, functions: Dict[str, Callable]):
         self._functions = functions
-        self._display_filter_parser = DisplayFilterParser(self._field_names, self._functions)
+        self._display_filter_parser = DisplayFilterParser(field_names=self._field_names, functions=self._functions)
 
     @abstractmethod
     def filter(self, display_filter: str):
@@ -132,7 +132,7 @@ def __init__(self,
         Initializes the DictDisplayFilter.
         :param data: A list of dictionaries to filter on.
         """
-        super().__init__(field_names, functions, slicers, evaluator)
+        super().__init__(field_names=field_names, functions=functions, slicers=slicers, evaluator=evaluator)
         self._data = data
 
     def filter(self, display_filter: str):
@@ -154,9 +154,9 @@ def __init__(self,
         Initializes the ListDisplayFilter.
         :param data: A list of lists to filter on.
         """
-        super().__init__([
+        super().__init__(data=[
             dict(zip(field_names, item)) for item in data
-        ], field_names, functions, slicers, evaluator)
+        ], field_names=field_names, functions=functions, slicers=slicers, evaluator=evaluator)
 
     def filter(self, display_filter: str):
         """ Filters the data using the display filter. """
@@ -190,7 +190,7 @@ def __init__(self,
         """
         self._connection = connection
         self.table_name = table_name
-        super().__init__(column_names, functions, slicers, evaluator)
+        super().__init__(field_names=column_names, functions=functions, slicers=slicers, evaluator=evaluator)
 
     def _validate_table_name(self, table_name: str) -> bool:
         """ Checks whether the table name contains invalid characters or keywords"""

pydictdisplayfilter/helpers.py

@@ -19,16 +19,35 @@
 import os
 import time
 import traceback
-from typing import List
+from collections import OrderedDict
+from itertools import chain
+from typing import List, Dict, Callable
 
 from pydictdisplayfilter.display_filters import BaseDisplayFilter, DictDisplayFilter
+from pydictdisplayfilter.evaluators import Evaluator
 from pydictdisplayfilter.exceptions import ParserError, EvaluationError
+from pydictdisplayfilter.slicers import BasicSlicer
 
 
 class TableError(Exception):
     pass
 
 
+class TableColumnSizeCalculator:
+
+    @staticmethod
+    def calculate(data_store: List[dict], fields: List) -> List[int]:
+        """ Calculates and returns the necessary size of each column in the data store. """
+        field_sizes = OrderedDict()
+        for field in fields:
+            field_sizes[field] = len(field)
+        for item in data_store:
+            for key in field_sizes.keys():
+                if key in item:
+                    field_sizes[key] = max(len(str(item[key])), field_sizes[key])
+        return list(field_sizes.values())
+
+
 class Table:
     """ Data store with filter capabilities and pretty table printout. """
 
@@ -39,22 +58,18 @@ def _make_table(self, data_store: List[dict]) -> List[str]:
         """ Creates a table including header from the data store. """
         if not data_store:
             return []
-        table = [self.fields()]
-        column_size = self._calculate_column_size(data_store)
+        fields = self.fields()
+        table = [fields]
+        column_size = self._calculate_column_size(data_store, fields)
         format_str = ' | '.join(["{{:<{}}}".format(i) for i in column_size])
         for item in data_store:
-            table.append(item.values())
-        column_size = self._calculate_column_size(data_store)
+            table.append([str(item[field]) if field in item else '' for field in fields])
         table.insert(1, ['-' * i for i in column_size]) # Separating line
         return [""] + [ format_str.format(*item) for item in table ]
 
-    def _calculate_column_size(self, data_store: List[dict]) -> List[int]:
+    def _calculate_column_size(self, data_store: List[dict], fields: List) -> List[int]:
         """ Calculates and returns the necessary size of each column in the data store. """
-        header = list(data_store[0].keys())
-        items = [list(item.values()) for item in data_store]
-        return [
-            max(len(str(item)) for item in column) for column in zip(*items + [header])
-        ]
+        return TableColumnSizeCalculator.calculate(data_store, fields)
 
     def _make_footer(self, items: List[dict], duration: float) -> List[str]:
         """ Creates a footer for the table which prints some statistics. """
@@ -70,7 +85,7 @@ def _make_footer(self, items: List[dict], duration: float) -> List[str]:
 
     def fields(self) -> List[str]:
         """ Returns the field names used in the data store. """
-        raise NotImplementedError()
+        return self._display_filter.field_names
 
     def filter(self, display_filter: str) -> str:
         """
@@ -177,22 +192,29 @@ def do_exit(self, *args):
 class DictTable(Table):
     """ Data store with filter capabilities and pretty table printout. """
 
-    def __init__(self, data_store: List[dict]):
+    def __init__(self,
+                 data_store: List[dict],
+                 field_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
         """ Initializes the DictTable with a data store. """
-        self._data_store = data_store
-        super().__init__(DictDisplayFilter(data_store))
+        field_names = field_names or self._extract_field_names(data_store)
+        super().__init__(DictDisplayFilter(data_store, field_names, functions, slicers, evaluator))
 
-    def fields(self) -> List[str]:
-        """ Returns the field names used in the data store. """
-        if not self._data_store:
-            # No items in data store, so there are no fields to query either.
-            return list()
-        return list(self._data_store[0].keys())
+    def _extract_field_names(self, data_store: List[dict]) -> List[str]:
+        """ Extracts the field names from the given data store. """
+        return sorted(set(chain.from_iterable(row.keys() for row in data_store)))
 
 
 class DictDisplayFilterShell(DisplayFilterShell):
     """ A little shell for querying a list of dictionaries using the display filter. """
 
-    def __init__(self, data_store: List[dict]):
+    def __init__(self,
+                 data_store: List[dict],
+                 field_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
         """ Initializes the DictDisplayFilterShell with a data store. """
-        super().__init__(DictTable(data_store))
+        super().__init__(DictTable(data_store, field_names, functions, slicers, evaluator))

pydictdisplayfilter/parsers/common.py

@@ -41,10 +41,6 @@ def _signed_float():
     )
 
 
-def _number():
-    return pp.common.integer
-
-
 def _string_list():
     return pp.delimitedList(
         _quoted_string()

setup.py

@@ -31,7 +31,8 @@
         'ipranger==1.1.2',
         'python-dateutil==2.8.2',
         'pytest==7.3.1',
-        'pytest-cov==4.0.0'
+        'pytest-cov==4.0.0',
+        'pexpect==4.8.0'
     ],
     include_package_data=True,
 )