如何使Python / Selenium等待文件处理，然后单击下载

Question

I'm trying to use Python/Selenium to automate the process of downloading a file that is updated daily. My code so far opens the website, selects the criteria I want (Downloading file in CSV format), and then clicks the "Start Processing" button. The way the website is set up, after you click "Start Processing", the site redirects you to a different page with a loading bar (indicating the completion of the processing) and a "cancel request" button, and after about ~10 seconds the file is ready and the "cancel request" button turns into a "Download my File" button. The file will progressively become larger as the year goes on so processing will go from ~10 seconds to a few (2-4) minutes. The processing will auto time out if it takes longer than 5 minutes. My "#Supposed to wait for the file to process" attempt was intended to wait until the ID "btn_download" (ID of the "Download my File" click) showed up before clicking the "Download my File" link. I think the code I have written to download the file will work since that same code worked to begin processing and they're both "Type: submit" links, but I am not sure if the reason I am not getting a download is because the "wait" code is not working properly, or if it is the "download code" (or both). I tried using "delay = x", driver.implicitly_wait(x), and "time.sleep(x)" and they did not work for me (I may have used them incorrectly I'm not sure). Ultimately the goal is to open the page, select the CSV criteria, begin processing, wait until processing is complete, download file, and save it to a folder in my hard drive (as opposed to leaving it in my downloads)

from selenium import webdriver
from selenium.common.exceptions import TimeoutException
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support.ui import Select
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC
from selenium.common.exceptions import NoSuchElementException

#Opens the website
browser = webdriver.Firefox() 
browser.get("https://mywebsite.com")

#Clicks CSV Option
browser.find_element_by_id("rdo_file").click()

#Starts Processing
browser.find_element_by_id("btnStart").click()

#Supposed to wait for the file to process 
try:
element = WebDriverWait(driver, 10).until(
    EC.visibility_of_element_located((By.ID, "btn_download"))
)

#Supposed to click the "Download my File" link
browser.find_element_by_id("btn_download").click()

Bonus points if you can help me download the file to a specific file in my harddrive! Thanks for the help!

Edited to add error message:

File "<stdline>" line 6
^
Syntax Error: invalid syntax

Also just realized that after that error message, Python allows me to hit enter again to process the "Download my File" code, which does work. So my problem lies with the wait code (need it to wait and continue the process automatically so I do not need to go back in and hit enter).

Answer 1

from selenium.webdriver.support import expected_conditions as EC

try:
    element = WebDriverWait(driver, 10).until(
        EC.presence_of_element_located((By.ID, "btn_download"))
    )
except:
    wait = WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.ID, 'btn_download')))
browser.find_element_by_id("btn_download").click()

Answer 2

As per your observation as the problem lies with the wait code and as per the HTML you have provided to click the button to start downloading the file you can use either of the following lines of code :

• CSS_SELECTOR & click() :

   WebDriverWait(driver, 300).until(EC.element_to_be_clickable((By.CSS_SELECTOR, "input#btn_download[name='btn_download'][value='Download My File']")).click() 

• CSS_SELECTOR & submit() :

   WebDriverWait(driver, 300).until(EC.element_to_be_clickable((By.CSS_SELECTOR, "input#btn_download[name='btn_download'][value='Download My File']")).submit() 

• XPATH & click() :

   WebDriverWait(driver, 300).until(EC.element_to_be_clickable((By.XPATH, "//input[@id='btn_download' and @name='btn_download' and @value='Download My File']")).click() 

• XPATH & submit() :

   WebDriverWait(driver, 300).until(EC.element_to_be_clickable((By.XPATH, "//input[@id='btn_download' and @name='btn_download' and @value='Download My File']")).submit() 

Note : As you mentioned the auto timeout is 5 minutes I have kept the maximum wait to equivalent to 300 seconds