How Can I Program to Wait and Try Again After Network Error in Python Wget

Wget is free command-line tool that you can use to download files from the internet.

In this wget tutorial, we volition learn how to install and how to employ wget.

What is Wget and What Does it Do?

WGET is a gratis tool to crawl websites and download files via the control line.

It lets you download files from the internet via FTP, HTTP or HTTPS (web pages, pdf, xml sitemaps, etc.).
Information technology provides recursive downloads, which means that Wget downloads the requested certificate, and then the documents linked from that document, and and then the next, etc.
Information technology follows the links and directory structure.
Information technology lets you overwrite the links with the correct domain, helping you create mirrors of websites.

Install Wget

Check if Wget is installed

Open Last and blazon:

If it is installed, it volition return the version.

If non, follow the next steps to download wget on either Mac or Windows.

Download Wget on Mac

The recommended method to install wget on Mac is with Homebrew.

First, install Homebrew.

$ carmine -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Then, install wget.

Download Wget on Windows

To install and configure wget for Windows:

Download wget for Windows and install the packet.
Copy thewget.exe file into your C:\Windows\System32 folder.
Open up thecommand prompt (cmd.exe) and run wget to see if information technology is installed.

Here is a quick video showing yous how to download wget on windows 10.

Wget Basics

Let'south look at the wget syntax, view the basic commands structure and understand the most of import options.

Wget Syntax

Wget has two arguments: [OPTION] and [URL] .

wget [OPTION]... [URL]...

[OPTION] tells what to practice with the [URL] argument provided after. It has a brusque and a long-form (ex: -5 and --version are doing the same matter).
[URL] is the file or the directory you wish to download.
You tin phone call many OPTIONS or URLs at in one case.

View WGET commands

To view bachelor wget commands, apply wget -h.

Extract Web pages with Wget Commands

Download a single file

$ wget https://instance.com/robots.txt

Download a File to a Specific Output Directory

Here replace <YOUR-PATH> by the output directory location where you want to save the file.

$ wget ‐P <YOUR-PATH> https://instance.com/sitemap.xml

Rename Downloaded File

To output the file with a different name:

$ wget -O <YOUR-FILENAME.html> https://example.com/file.html

Ascertain User Amanuensis

Place yourself. Ascertain your user-agent.

$ wget --user-agent=Chrome https://example.com/file.html

$ wget --user-agent="Mozilla/five.0 (Linux; Android half dozen.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, similar Gecko) Chrome/86.0.4240.198 Mobile Safari/537.36 (compatible; Googlebot/2.i; +http://www.google.com/bot.html)" https://example.com/path

Let'south extract robots.txt simply if the latest version in the server is more than recent than the local copy.

First time that you excerpt utilize -S to go along a timestamps of the file.

$ wget -South https://instance.com/robots.txt

Later, to cheque if the robots.txt file has changed, and download it if it has.

$ wget -N https://example.com/robots.txt

Convert Links on a Page

Convert the links in the HTML so they still work in your local version. (ex: example.com/path to localhost:8000/path)

$ wget --catechumen-links https://example.com/path

Mirror a Single Webpage

To mirror a single spider web page then that it tin work on your local.

$ wget -Due east -H -k -K -p --catechumen-links https://example.com/path

Add all urls in a urls.txt file.

https://case.com/1 https://example.com/2 https://example.com/iii

Limit Speed

To exist a proficient denizen of the web, it is important not to crawl too fast by using --look and --limit-rate.

--wait=i: Look 1 second betwixt extractions.
--limit-charge per unit=10K: Limit the download speed (bytes per second)

Recursive manner extract a page, and follows the links on the pages to extract them equally well.

This is extracting your entire site and can put extra load on your server. Be sure that you know what you lot do or that you involve the devs.

$ wget --recursive --folio-requisites --accommodate-extension --span-hosts --look=1 --limit-rate=10K --catechumen-links --restrict-file-names=windows --no-clobber --domains case.com --no-parent example.com

--recursive: Follow links in the certificate. The maximum depth is 5.
--page-requisites: Get all assets (CSS/JS/images)
--adjust-extension: Save files with .html at the end.
--span-hosts: Include necessary assets from offsite also.
--wait=1: Expect ane second betwixt extractions.
--limit-rate=10K: Limit the download speed (bytes per 2nd)
--convert-links: Catechumen the links in the HTML so they nonetheless work in your local version.
--restrict-file-names=windows: Change filenames to work in Windows.
--no-clobber : Overwrite existing files.
--domains example.com: Practice non follow links exterior this domain.
--no-parent: Exercise not e'er ascend to the parent directory when retrieving recursively
--level : Specify the depth of crawling. inf is used for infinite.

$ wget --spider -r https://example.com -o wget.log

Wget VS Roll

Wget's strength compared towhorl is its ability to download recursively. This means that it will download a document, then follow the links and then download those documents too.

Use Wget With Python

Wget is strictly command line, but in that location is a bundle that you can import the wget package that mimics wget.

import wget url = 'https://www.jcchouinard.com/robots.txt' filename = wget.download(url) filename

Debug Wget Command Not Plant

If you go the -fustigate: wget: command not constitute error on Mac, Linux or Windows, it means that the wget GNU is either not installed or does not work properly.

Go back and brand certain that you installed wget properly.

Determination

This is it.

You now know how to install and use Wget in your control-line.

Sr SEO Specialist at Seek (Melbourne, Commonwealth of australia). Specialized in technical SEO. In a quest to programmatic SEO for large organizations through the use of Python, R and machine learning.

nicolaspladithe.blogspot.com

Source: https://www.jcchouinard.com/wget/