How to use the command 'linkchecker' (with examples)

Linkchecker is a command-line client that allows you to check HTML documents and websites for broken links. It is a useful tool for website developers and administrators to ensure the integrity of their websites by identifying broken links.

Use case 1: Find broken links on a website

Code:

linkchecker https://example.com/

Motivation: When building and maintaining a website, it is important to identify broken links to ensure a smooth user experience. By running the ’linkchecker’ command with the URL of the website, you can easily find any broken links on the site.

Explanation:

• linkchecker: This is the command used to invoke the linkchecker tool.
• https://example.com/: This is the URL of the website that you want to check for broken links. Replace it with the actual URL of your website.

Example output:

LinkChecker 9.4.0 started...

URL                                  result  status        check time
------------------------------------------------------------------------
https://example.com/                 error   404 Not Found  0.232s
https://example.com/page1            ok      200 OK         0.092s
https://example.com/page2            ok      200 OK         0.128s

Checked 3 links in 0.467 seconds

Use case 2: Check URLs that point to external domains

Code:

linkchecker --check-extern https://example.com/

Motivation: In addition to checking the broken links within a website, it is also important to ensure that the external URLs used on the website are not broken. By using the --check-extern option, you can instruct linkchecker to also scan the external URLs and check their integrity.

Explanation:

• --check-extern: This is an option that tells linkchecker to check the URLs that point to external domains as well.
• https://example.com/: This is the URL of the website that you want to check. Replace it with the actual URL of your website.

Example output:

LinkChecker 9.4.0 started...

URL                                  result  status        check time
------------------------------------------------------------------------
https://example.com/                 error   404 Not Found  0.232s
https://externaldomain.com/page1      ok      200 OK         0.182s
https://externaldomain.com/page2      ok      200 OK         0.150s

Checked 3 links in 0.564 seconds

Use case 3: Ignore URLs that match a specific regular expression

Code:

linkchecker --ignore-url regular_expression https://example.com/

Motivation: There might be certain URLs on your website that you want to exclude from the link checking process. This could be URLs for external resources, dynamically generated pages, or any other URLs that you don’t want to be considered as broken links. By using the --ignore-url option with a regular expression, you can specify which URLs to ignore.

Explanation:

• --ignore-url: This is an option that allows you to specify a regular expression to match the URLs that should be ignored during the link checking process.
• regular_expression: This is a placeholder for the actual regular expression that you want to use. Replace it with your desired regular expression.
• https://example.com/: This is the URL of the website that you want to check. Replace it with the actual URL of your website.

Example output:

LinkChecker 9.4.0 started...

URL                                  result  status        check time
------------------------------------------------------------------------
https://example.com/                 ok      200 OK         0.125s
https://example.com/page1            ok      200 OK         0.114s
https://example.com/page2            ok      200 OK         0.132s

Checked 3 links in 0.371 seconds

Use case 4: Output results to a CSV file

Code:

linkchecker --file-output csv/path/to/file https://example.com/

Motivation: Sometimes, it can be useful to save the results of the link checking process for future reference or analysis. By using the --file-output option with the desired file path and format (in this case, CSV), you can instruct linkchecker to save the results to a file.

Explanation:

• --file-output: This is an option that allows you to specify the file path and format for the output results.
• csv/path/to/file: This is a placeholder for the actual file path and name where you want to save the results. Replace it with the desired file path and name.
• https://example.com/: This is the URL of the website that you want to check. Replace it with the actual URL of your website.

Example output: The output will not be displayed on the command line, but it will be saved as a CSV file at the specified file path.

Conclusion:

The ’linkchecker’ command is a powerful tool for checking HTML documents and websites for broken links. With its various options and capabilities, it enables developers and administrators to ensure the integrity of their websites and provide a seamless user experience. Whether you need to find broken links, check external URLs, ignore specific URLs, or save the results to a file, linkchecker has you covered.