Added "enforce" field to BuildQuery, for being able of enforcing returning lists.

vizgrimoire/GrimoireSQL.py

@@ -87,17 +87,78 @@ def SetDBChannel (user=None, password=None, database=None,
     cursor = db.cursor()
     cursor.execute("SET NAMES 'utf8'")
 
-def ExecuteQuery (sql):
-    result = {}
+def ExecuteQuery (sql, enforce = None):
+    """Execute query, return results.
+
+    Returns the results of executing the specified SQL query, as a
+    dictionary. In this dictionary, keys are field names for the query
+    results, values are the corresponding value(s) for the corresponding
+    field in all rows.
+
+    Depending on the value of the parameter 'enforce', results will
+    be enforced to be a list, or (default behavior, for compatibility),
+    a list if results are more than one row, or single values if the
+    result is only one row. If result is 0 rows, an empty list will always
+    be returned for each key.
+
+    For example, if the following values are returned by the query
+    (assuming each line is a row, first line is the name of fields):
+
+    "Field A", "Field B"
+    "String 1", 1
+    "String 2", 2
+
+    the returning dictionary will be
+
+    {"Field A": ["String 1", "String 2"],
+     "Field B": [1, 2]
+    }
+
+    If query results is just one row, and enforce == "list", the result
+    is as follows:
+
+    {"Field A": ["String 1"],
+     "Field B": [1]
+    }
+
+    In the same case, enforce == None, the result is:
+
+    {"Field A": "String 1",
+     "Field B": 1
+    }
+
+    If query results is 0 rows:
+
+    {"Field A": [],
+     "Field B": []
+    }
+
+    If for some reason the the description of the fields cannot be obtained,
+    it returns None (if enforce =) "list") or empty directory
+    (if enforce == None). Probably it should raise an exception.
+
+    :param sql: SQL string to execute
+    :param enforce: enforce some kind of result, "list" or None (default)
+
+    :returns result of executing the SQL string
+
+    """
+
     cursor.execute(sql)
     rows = cursor.rowcount
     columns = cursor.description
 
-    if columns is None: return result
+    if columns is None:
+        if enforce == "list":
+            return None
+        else:
+            return {}
+
+    result = {}
 
     for column in columns:
         result[column[0]] = []
-    if rows > 1:
+    if rows > 1 or ((rows == 1) and (enforce == "list")):
         for value in cursor.fetchall():
             for (index,column) in enumerate(value):
                 result[columns[index][0]].append(column)

vizgrimoire/analysis/top_questions_qaforums.py

@@ -63,7 +63,7 @@ def top_commented(self):
                 group by q.question_identifier
                 order by comments desc limit %s
                 """ % (self.filters.startdate, self.filters.enddate, self.filters.npeople)
-        return self.db.ExecuteQuery(query)
+        return self.db.ExecuteQuery(query, enforce = "list")
 
     def top_visited(self):
         # The top visited questions are those questions with the 

vizgrimoire/metrics/query_builder.py

@@ -222,19 +222,88 @@ def __SetDBChannel__ (self, user=None, password=None, database=None,
 
         return db
 
-    def ExecuteQuery (self, sql):
-        if sql is None: return {}
+    def ExecuteQuery (self, sql, enforce = None):
+        """Execute query, return results.
+
+        Returns the results of executing the specified SQL query, as a
+        dictionary. In this dictionary, keys are field names for the query
+        results, values are the corresponding value(s) for the corresponding
+        field in all rows.
+
+        Depending on the value of the parameter 'enforce', results will
+        be enforced to be a list, or (default behavior, for compatibility),
+        a list if results are more than one row, or single values if the
+        result is only one row. If result is 0 rows, an empty list will always
+        be returned for each key.
+
+        For example, if the following values are returned by the query
+        (assuming each line is a row, first line is the name of fields):
+
+        "Field A", "Field B"
+        "String 1", 1
+        "String 2", 2
+
+        the returning dictionary will be
+
+        {"Field A": ["String 1", "String 2"],
+        "Field B": [1, 2]
+        }
+
+        If query results is just one row, and enforce == "list", the result
+        is as follows:
+
+        {"Field A": ["String 1"],
+        "Field B": [1]
+        }
+
+        In the same case, enforce == None, the result is:
+
+        {"Field A": "String 1",
+        "Field B": 1
+        }
+
+        If query results is 0 rows:
+
+        {"Field A": [],
+        "Field B": []
+        }
+
+        If for some reason the the description of the fields cannot be obtained,
+        it returns None (if enforce =) "list") or empty directory
+        (if enforce == None). Probably it should raise an exception.
+
+        :param sql: SQL string to execute
+        :param enforce: enforce some kind of result, "list" or None (default)
+
+        :returns result of executing the SQL string
+
+        :raises ValueError: when sql is None (and enforce is not None)
+
+        """
+
+
+        if sql is None:
+            if enforce is not None:
+                raise ValueError ('sql string cannot be none')
+            else:
+                return {}
         # print sql
-        result = {}
         self.cursor.execute(sql)
         rows = self.cursor.rowcount
         columns = self.cursor.description
 
-        if columns is None: return result
+        if columns is None:
+            # Description failed
+            if enforce is not None:
+                return None
+            else:
+                return {}
+
+        result = {}
 
         for column in columns:
             result[column[0]] = []
-        if rows > 1:
+        if rows > 1 or ((rows == 1) and (enforce == "list")):
             for value in self.cursor.fetchall():
                 for (index,column) in enumerate(value):
                     result[columns[index][0]].append(column)