Python read filenames and save in list - python-2.7

Question

I need to read all files in a directory and save into list, then read list those files one by one.
I don't want to use external module like 'glob module'. So, trying through 2 different approach:
First approach:
import os
file_list = os.listdir("jsons")
for files in file_list:
data = open(files,"r")
output:
['A03DUrQz1BM9SQ2.json', 'A04D5V1u1BMxaV6.json', 'A0kxiHL81AN9pH5.json', 'A1Fxs5Ag1A8vuB5.json', 'A2Dsv7RE1BDqYt5.json', 'A2HkZPkn1BpvvG5.json']
but here issue is that filenames are saved in string format and not able to open this file as it read it with quotes ''.
2nd approach:
file_list = os.system("ls jsons/")
**print file_list.split()**
for files in file_list:
data = open(files,"r")
print data
output:
Traceback (most recent call last):
File "asn-1_q3.py", line 9, in <module>
print file_list.split()
AttributeError: 'int' object has no attribute 'split'
Here, it is saving as int and not able to split the file.
How should I solve them ?

Answer 1

You need to read your file object and os.path.join the file name with the original directory name (or it will look for the files in the current directory):
import os
import os.path
file_list = os.listdir("jsons")
for file_name in file_list:
with open(os.path.join("jsons", file_name), "r") as src_file:
data = src_file.read()
print(data)
Here's an example that uses generators to limit the amount of data in memory (vs loading all the data into an array):
import os
os.path
def all_file_content(directory_name):
file_list = os.listdir(directory_name)
for file_name in file_list:
with open(os.path.join(directory_name, file_name), "r") as src_file:
yield src_file.read()
for file_content in all_file_content("jsons"):
print(file_content)