Python Urrlib if File Already Downloaded Dont Download Again
Downloading multiple files from the Cyberspace manually as part of your daily routine can truly be a nightmare. And if you're looking for a way to automate your file downloads, then Python's Wget is the right tool for yous.
In this tutorial, you lot'll acquire many ways to download files, from running the basic Python wget command to creating a script to download multiple files simultaneously.
Permit's get down to it!
Prerequisites
This tutorial will be a easily-on demonstration. If you'd like to follow along, exist sure you have the following:
- Virtual Studio Code (VS Code) – This tutorial uses Virtual studio code version 1.58.2 (64 bit).
Related: What You Need to Know about Visual Studio Code: A Tutorial - Python – This tutorial will be using Python v3.9.six.
- A Windows PC -This tutorial uses Windows 10 for demonstrations but works for Windows 7 and eight.1.
Downloading and Installing Wget on Windows
Wget is a non-interactive utility to download remote files from the internet. Aside from being congenital-in with Unix-based OS, the wget command also has a version built for Windows Bone. At the time of writing, the latest Wget Windows version is 1.21.six.
Before you download files with the wget command, let'southward go over how to download and install Wget on your Windows PC first.
i. Download Wget either for 64bit or 32bit for Windows.
2. Open File Explorer and find the wget.exe file you downloaded, then copy and paste it to the C:\Windows\System32 directory to add wget.exe to the PATH environment variable. The PATH environment variable specifies sets of directories to be searched to find a control or run executable programs.
Calculation wget.exe in the PATH surroundings variable lets you run the wget control from any working directory in the command prompt.
3. Now, launch the command prompt and ostend the version (--version) of Wget (wget) you downloaded with the command below.
In one case y'all see the output on the screenshot below, then Wget is successfully installed in your motorcar.
Downloading a File Direct from a URL
Now that y'all've installed Wget, allow's dig into running basic wget commands. Perhaps you want to download a file from a specific URL. In that instance, you just need the basic wget command syntax and specify the URL to download the file from.
Related: Download a File with an Culling PowerShell wget Command
Below, you tin see the basic syntax for running the wget command. Notice that after the wget command, yous'll specify various options followed by the website URL.
Downloading a File to the Working Directory
With the wget command syntax you learned still fresh in your memory, let'southward expect at downloading a file to the working directory past running the wget without added options.
Run the control below to download the wget.exe file from the specified URL (https://eternallybored.org/misc/wget/1.21.1/64/wget.exe) to the working directory.
wget https://eternallybored.org/misc/wget/i.21.one/64/wget.exe In one case you see this output on your command prompt, the file has been downloaded successfully.
Downloading a File to a Specific File Path
You've just downloaded a file to your working directory, only what if you lot prefer to download the file to a specific file path? If so, then run the below command instead to specify the download location.
Run the wget command below and add the --directory-prefix option to specify the file path (C:\Temp\Downloads) to save the file you lot're downloading.
wget ‐‐directory-prefix=C:\Temp\Downloads https://eternallybored.org/misc/wget/1.21.1/64/wget.exe Open File Explorer and navigate to the download location yous specified (C:\Temp\Downloads) to confirm that you lot've successfully downloaded the file.
Downloading and Renaming a File
Downloading a file to your preferred directory with a single command is cool plenty. Simply perhaps you'd similar to download a file with a unlike name. If and then, the -o flag is the answer! Adding the -o flag lets you output the file you're downloading with a different name.
Below, run the basic wget control syntax to download the wget.exe file from a specific URL. But this time, add the -o flag to rename the file you're downloading. So instead of wget.exe, you're naming the file new_get.exe.
wget -o new_wget.exe https://eternallybored.org/misc/wget/one.21.ane/64/wget.exe Yous tin can see below in File Explorer that the downloaded file is named new_wget.exe.
Downloading a File's Newer Version
Possibly you desire to download a newer version of a file yous previously downloaded. If so, adding the --timestamp pick in your wget command will do the trick. Applications on a website tend to exist updated over fourth dimension, and the --timestamp choice checks for the updated version of the file in the specified URL.
The wget command below checks (--timestamp) and downloads the newer version of the wget.exe file to the C:\Temp\Downloads directory.
wget ‐‐timestamp ‐‐directory-prefix=C:\Temp\Downloads https://eternallybored.org/misc/wget/1.21.1/64/wget.exe If the file (wget.exe) were modified from the version you specified, y'all'd get a similar output as in the previous examples. Merely if not, you'll see the screenshot beneath. Notice the office where it says Not Modified, indicating in that location'due south no new newer version of the file you lot're downloading.
Downloading Files from a Website Requiring Username and Password
Most websites require a user to be logged in to access or download some files and content. To make this possible, Wget offers the --user and --password options. With these options, Wget provides a username and password to authenticate your connectedness asking when downloading from a website.
Beneath is the basic syntax of the wget control to download files from websites requiring your business relationship'south username (myusername) and password (mypassword).
wget --user=myusername --ask-password=mypassword https://downloads.mongodb.com/compass/mongodb-compass-one.28.one-win32-x64.zip Yous will come across an output like in the image beneath if the control is successful.
Downloading a Web Folio
Instead of a file, perhaps you're trying to download a web page to keep a local re-create. In that case, you'll run a like command that downloads a file, but with boosted options.
Run the wget command below to download the home folio of the http://domain.com/ website and create a folder named domain.com in the working directory. The domain.com folder is where the downloaded dwelling house page is saved (-o).
The command besides creates a log file in the working directory instead of printing output on the console.
wget -r http://domain.com/ -o log Beneath, you'll see the local re-create of the downloaded web page and log file where the download logs are saved.
Yous may also put several options together, which exercise not crave arguments. Below, yous tin see that instead of writing options separately (-d -r -c), you tin combine them in this format (-drc).
wget -d -r -c http://domain.com/ -o log # Standard option annunciation wget -drc http://domain.com/ -o log # Combined options Downloading an Entire Website
Rather than only a single web page, you may also desire to download an entire website to see how the website is built. To do so, y'all'll need to configure the wget control as follows:
- Replicate (
--mirror) the website (www.domain.com), and ensure all files (-p), including scripts, images, etc., are included in the download. - Now add the
-Poption to set a download location (./local-dir). - Ensure you lot download the specific website only by adding the
--catechumen-linksoption to your control. Most websites have pages with links pointing to a resource for other websites. You're likewise downloading all other linked websites when y'all download a website, which yous may not need.
wget --mirror -p --catechumen-links -P ./local-dir http://www.domain.com/ Once you see the below output, the file has been downloaded successfully.
Wget downloads all the files that make up the entire website to the local-dir folder, as shown beneath.
The command below outputs the same result as the previous one you executed. The difference is that the --await option sets a 15-second interval in downloading each web folio. While the --limit option sets the download speed limit to 50Kmbps.
wget --mirror -p --catechumen-links -P ./local-dir --wait=15 --limit-rate=50K http://www.domain.com/ Downloading Files from Dissimilar URLs Simultaneously
As yous did in the previous examples, downloading files manually each mean solar day is plain a deadening task. Wget offers the flexibility to download files from multiple URLs with a single command, requiring a single text file.
Sounds like a good bargain? Let's get down to information technology!
Open your favorite text editor and put in the URLs of the files you wish to download, each on a new line, like the prototype below.
Now, run the command beneath to download the files from each URL yous listed in the text file.
Below, y'all can see the output of each file's download progress.
Resuming an Interrupted Download
By now, you already know your way of downloading files with the wget command. Simply perhaps, your download was interrupted during the download. What would you practice? Another not bad characteristic of wget is the flexibility to resume an interrupted or failed download.
Below is an example of an interrupted download as you lost your internet connection. Find that the download progress (7%) gets stuck, and the eta keeps counting upwardly.
The download progress will automatically resume when you get your internet connectedness dorsum. But in other cases, like if the command prompt unexpectedly crashed or your PC rebooted, how would you keep the download? The --keep option will surely save the day.
Run the wget command below to continue (--continue) an interrupted download of the wget.exe file.
wget --continue https://download.techsmith.com/snagit/releases/snagit.exe You can run into below that the interrupted download resumed at 7% when interrupted (non ever). Yous'll likewise see the total and remaining file size to download.
Alternatively, you lot may want to set a certain number of times the wget command will retry a failed or interrupted download.
Add the --tries option in the wget command below that sets 10 tries to complete downloading the wget.exe file if the download fails. To demonstrate how the --tries choice works, interrupt the download by disconnecting your computer from the internet as soon every bit you run the command.
wget --tries=10 https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png Beneath, you can see that the download stops, and the HTTP asking is awaiting a response.
At present, reconnect your calculator to the internet, and you'll see the download will automatically continue, as shown below. You tin can see that information technology's the 2nd try to download the file.
Creating a Python Script for Downloading Files
Y'all've learned how to download files by running commands then far, but did you lot know yous can besides create a script to download files automatically? Let's dive into writing some Python code.
i. Create a new binder named ~downloader.
2. Launch VS Code, and so click on the File menu —> Open up Folder to open the ~downloader folder you created.
3. Click on the new file icon to create a new Python script file named app.py in your project directory, as shown below.
4. Now, click on the Terminal menu, and cull New Terminal to open a new control-line terminal, as shown below.
Installing and Activating Virtual Environment
Now that y'all have your project binder and script file, let's dig into creating a virtual environs. A virtual environment is an isolated environment for Python projects where the packages required for your project are installed. You'll activate this virtual environs to enable the execution of your plan in the future.
Run the beneath commands on your VS Code terminal to install the virtual environs package and create a virtual environment.
pip install virtualenv # Install Virtual Environment Package virtualenv download # Create a Virtual Environment named 'download' Run either of the commands below depending on your operating system to activate your virtual environs.
source download/bin/actuate # Activate Virtual Environs for Unix/Mac download\Scripts\activate # Activate Virtual Environment for Windows Installing wget Module
You now have your virtual surround set up, then it's time to install the wget module. The wget module is adult to provide an API for the Python developers' community. This module eases the applications and implementations of the wget command with Python
When building a Python project, you need to store the packages in a requirements.txt file. This file volition help you install the same version of the packages used in the future.
Run the commands below to install the Wget module and add it to the requirements.txt file.
pip install wget # Install the wget module pip freeze > requirements.txt # Add wget to requirements.txt Now re-create and paste the lawmaking below to the app.py you lot previously created in VS Lawmaking.
The code below changes the output of the file download so that you lot can meet each file download's progress with a custom progress bar.
# import the wget module from wget import download # # create a downloader grade. class downloader: # Create a custom prgress bar method def progressBar(self,current,total): impress("Downloading: %d%% [%d / %d] bytes" % (current / total * 100, current, total)) # Create a downloadfile method # Accepting the url and the file storage location # Set the location to an empty string past default. def downloadFile(self, url, location=""): # Download file and with a custom progress bar download(url, out = location, bar = self.progressBar) downloadObj = downloader() downloadObj.downloadFile("https://weblog.debugeverything.com/wp-content/uploads/2021/04/python-virtualenv-project-structure.jpg","files") Finally, run the command below to execute the script app.py script.
Beneath, y'all can see each file's download progress in percent with the file's full and current downloaded size in bytes.
Decision
Throughout this tutorial, you've learned how to download files with Python wget control. Yous've too experienced downloading files from running basic wget commands to running the wget module in Python script to download multiple files.
At present, how would you employ Python Wget in your next project to download files automatically? Perhaps creating a scheduled download task?
Source: https://adamtheautomator.com/python-wget/
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