refactor parser:csv parser

Author: Akol125

lambdas/shared/src/common/validator/parsers/csv_line_parser.py

@@ -30,5 +30,5 @@ def parse_csv_line(self, csv_row: str, csv_header: str) -> None:
 
     # Retrieves the value of a specific column name as a list.
     def get_key_value(self, field_name: str) -> list[str]:
-        data = [self.csv_file_data[field_name]]
-        return data
+        retrieve_column_data = [self.csv_file_data[field_name]]
+        return retrieve_column_data

lambdas/shared/src/common/validator/parsers/csv_parser.py

@@ -1,28 +1,31 @@
-# CSV importer and data access
+"""
+Reads and parses the specified CSV file into a dictionary of lists.
+
+Each key in the dictionary corresponds to a CSV column header, and
+each value is a list containing all entries under that header.
+
+csv_filename (str): The path to the CSV file to parse.
+delimiter (str): The field delimiter used in the CSV file. Defaults to '|'.
+"""
+
 import csv
 
 
 class CSVParser:
-    """File Management"""
-
-    # parser variables
     def __init__(self):
         self.csv_file_data = {}
 
     # parse the CSV into a Dictionary
-    def parse_csv_file(self, csv_filename):
-        input_file = csv.DictReader(open(csv_filename))
-        input_file = csv.DictReader(open(csv_filename), delimiter="|")
-        self.csv_file_data = {elem: [] for elem in input_file.fieldnames}
-        keys = self.csv_file_data.keys()
-        for row in input_file:
-            for key in keys:
-                self.csv_file_data[key].append(row[key])
+    def parse_csv_file(self, csv_filename: str, delimiter: str = "|") -> None:
+        with open(csv_filename, newline="", encoding="utf-8") as file:
+            csv_to_dict = csv.DictReader(file, delimiter=delimiter)
+            self.csv_file_data = {headers: [] for headers in csv_to_dict.fieldnames}
+            csv_header_to_keys = self.csv_file_data.keys()
+            for row in csv_to_dict:
+                for key in csv_header_to_keys:
+                    self.csv_file_data[key].append(row[key])
 
-    # ---------------------------------------------
-    # Scan and retrieve values
     # retrieve a column of data to work with
-    def get_key_value(self, field_name):
-        # creating empty lists
-        data = self.csv_file_data[field_name]
-        return data
+    def get_key_value(self, field_name: str) -> list[str]:
+        retrieve_column_data = self.csv_file_data[field_name]
+        return retrieve_column_data