reading gpio pins of raspberry pi

Question

I am using 8 channel relay, with raspberry pi 3 and programming in python. i want to read or sense the pins if they or low every 5 seconds and to print the output in .txt or .csv file. for single pin I have attached the code and it working fine but how i can expand to all 8 channels (relays).

Python code:

import time 
from time import sleep  # Allows us to call the sleep function to slow down 
 our loop
import RPi.GPIO as GPIO # Allows us to call our GPIO pins and names it just 
GPIO

GPIO.setmode(GPIO.BCM)  # Set's GPIO pins to BCM GPIO numbering
INPUT_PIN = 26          # Write GPIO pin number.
GPIO.setup(INPUT_PIN, GPIO.IN)  # Set our input pin to be an input
# Start a loop that never ends
while True:
        if (GPIO.input(INPUT_PIN) == True):
            # load is turned off.
           print (time.strftime ("%Y/%m/%d , %H:%M:%S"),"0")
        else:
            #now 20 watt load is turned ON!.
            print(time.strftime ("%Y/%m/%d , %H:%M:%S"),"20")
        sleep(10);       # Sleep for 10 seconds.

and i want to save all the data in a .csv or .txt file with time stamp at the start and other 8 columns for pins status that are connected with relay.

My output should look like:

06/01/2018,18:54:00,1,0,1,1,1,0,0,0  
06/01/2018,18:54:05,1,0,1,1,1,0,0,0  
06/01/2018,18:54:10,1,0,1,1,1,0,0,0  
06/01/2018,18:54:15,1,0,1,1,1,0,0,0  
06/01/2018,18:54:20,0,0,0,0,0,0,0,0

Answer 1

import csv
import time 
from time import sleep  
import RPi.GPIO as GPIO 

GPIO.setmode(GPIO.BCM)

INPUT_PINS = [26, 27, 28, ] # FILL ALL 8 PIN NUMBERS HERE

[GPIO.setup(pin, GPIO.IN) for pin in INPUT_PINS]

while True:
    output = []
    for pin in INPUT_PINS:
        if (GPIO.input(pin) == True):
            # load is turned off.
            value = 0
        else:
            #now 20 watt load is turned ON!.
            value = 20
        output.append(value)

    with open('logs.csv', 'wa') as csvfile:
        logcsv = csv.writer(csvfile, delimiter=',')
        logcsv.writerow([time.strftime ("%Y/%m/%d , %H:%M:%S")] + output)


    sleep(10);