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Preuzimanje datoteka s weba pomoću Pythona

Zahtjevi je svestrana HTTP biblioteka u pythonu s raznim aplikacijama. Jedna od njegovih primjena je preuzimanje datoteke s weba koristeći URL datoteke. Montaža: First of all you would need to download the requests library. You can directly install it using pip by typing following command:
pip install requests
Or download it directly from ovdje i instalirati ručno.

Preuzimanje datoteka

Python3
# imported the requests library import requests image_url = 'https://www.python.org/static/community_logos/python-logo-master-v3-TM.webp' # URL of the image to be downloaded is defined as image_url r = requests.get(image_url) # create HTTP response object # send a HTTP request to the server and save # the HTTP response in a response object called r with open('python_logo.webp''wb') as f: # Saving received content as a png file in # binary format # write the contents of the response (r.content) # to a new file in binary mode. f.write(r.content) 
This small piece of code written above will download the following image from the web. Now check your local directory(the folder where this script resides) and you will find this image: All we need is the URL of the image source. (You can get the URL of image source by right-clicking on the image and selecting the View Image option.)

Preuzmite velike datoteke

Sadržaj HTTP odgovora ( r. sadržaj ) nije ništa drugo nego niz koji pohranjuje podatke datoteke. Stoga neće biti moguće spremiti sve podatke u jednom nizu u slučaju velikih datoteka. Kako bismo prevladali ovaj problem, napravili smo neke promjene u našem programu:
  • Budući da se svi podaci datoteke ne mogu pohraniti pomoću jednog niza koji koristimo r.iter_sadržaj metoda za učitavanje podataka u komadima uz navođenje veličine komada.
  •  r = requests.get(URL stream = True)
    Setting potok parametar za Pravi uzrokovat će preuzimanje samo zaglavlja odgovora i veza ostaje otvorena. Time se izbjegava čitanje cijelog sadržaja u memoriju za velike odgovore. Fiksni komad će se učitati svaki put dok r.iter_sadržaj is iterated. Here is an example: Python3
    import requests file_url = 'http://codex.cs.yale.edu/avi/db-book/db4/slide-dir/ch1-2.pdf' r = requests.get(file_url stream = True) with open('python.pdf''wb') as pdf: for chunk in r.iter_content(chunk_size=1024): # writing one chunk at a time to pdf file if chunk: pdf.write(chunk) 

    Preuzimanje videa



    U ovom primjeru zainteresirani smo za preuzimanje svih dostupnih video predavanja o tome web-stranica . Sva arhiva ovog predavanja je dostupna ovdje . So we first scrape the webpage to extract all video links and then download the videos one by one. Python3
    import requests from bs4 import BeautifulSoup '''  URL of the archive web-page which provides link to  all video lectures. It would have been tiring to  download each video manually.  In this example we first crawl the webpage to extract  all the links and then download videos.  ''' # specify the URL of the archive here  archive_url = 'https://public.websites.umich.edu/errors/404.html def get_video_links(): # create response object  r = requests.get(archive_url) # create beautiful-soup object  soup = BeautifulSoup(r.content'html5lib') # find all links on web-page  links = soup.findAll('a') # filter the link sending with .mp4  video_links = [archive_url + link['href'] for link in links if link['href'].endswith('mp4')] return video_links def download_video_series(video_links): for link in video_links:  '''iterate through all links in video_links   and download them one by one''' # obtain filename by splitting url and getting  # last string  file_name = link.split('/')[-1] print( 'Downloading file:%s'%file_name) # create response object  r = requests.get(link stream = True) # download started  with open(file_name 'wb') as f: for chunk in r.iter_content(chunk_size = 1024*1024): if chunk: f.write(chunk) print( '%s downloaded!n'%file_name ) print ('All videos downloaded!') return if __name__ == '__main__': # getting all video links  video_links = get_video_links() # download all videos  download_video_series(video_links) 
    Advantages of using Requests library to download web files are:
    • Web imenike možete jednostavno preuzeti rekurzivnim ponavljanjem kroz web mjesto!
    • Ovo je metoda neovisna o pregledniku i mnogo je brža!
    • Možete jednostavno strugati web-stranicu da biste dobili sve URL-ove datoteka na web-stranici i stoga preuzeti sve datoteke u jednoj naredbi-

      Implementacija Web Scrapinga u Pythonu uz BeautifulSoup

    Ovaj blog je napravio Nikhil Kumar.