Read lines from a text file containing dictionaries into elements of list-CodePudding

I have a text file that looks like this

{'tableName': 'customer', 'type': 'VIEW'}
{'tableName': 'supplier', 'type': 'TABLE'}
{'tableName': 'owner', 'type': 'VIEW'}

I want to read it into a python program that stores it into a list of dictonaries like this

expectedOutput=[{'tableName': 'customer', 'type': 'VIEW'},{'tableName': 'supplier', 'type': 'TABLE'},{'tableName': 'owner', 'type': 'VIEW'}]

But the output I get is a list of strings

       output = ["{'tableName': 'customer', 'type': 'VIEW'}",
      "{'tableName': 'supplier', 'type': 'TABLE'}",
      "{'tableName': 'owner', 'type': 'VIEW'}"]

The code I run is

my_file3 = open("textFiles/python.txt", "r")
data3 = my_file3.read()
output = data3.split("\n")

Can someone show me how do I store the entries inside the list as dicts and not strings. Thank you

CodePudding user response：

You can use eval but it can be dangerous (only do this if you trust the file):

my_file3 = open("textFiles/python.txt") # specifying 'r' is unnecessary
data3 = my_file3.read()
output = [eval(line) for line in data3.splitlines()] # use splitlines() rather than split('\n')

If the file contains something like __import__('shutil').rmtree('/') it could be very dangerous. Read the documentation for eval here

If you don't fully trust the file, use ast.literal_eval:

import ast
my_file3 = open("textFiles/python.txt")
data3 = my_file3.read()
output = [ast.literal_eval(line) for line in data3.splitlines()]

This removes the risk - if the file contains something like an import, it will raise a ValueError: malformed node or string. Read the documentation for ast.literal_eval here

Output:

[{'tableName': 'customer', 'type': 'VIEW'},
 {'tableName': 'supplier', 'type': 'TABLE'},
 {'tableName': 'owner', 'type': 'VIEW'}]

CodePudding user response：

You can use the json module

import json
my_file3 = open("textFiles/python.txt", "r")
data3 = my_file3.read()
output = json.loads(str(data3.splitlines()))
print(output)

As Thonnu warned, eval is quite dangerous