Local File Server

The Local File Server extension enables web sites to link to local files via "http://localhost/" URLs. For security reasons, Chrome blocks "file://" URLs to local files in remote web pages. Some web services, like for instance Gmail, don't even render such URLs. Though, there are circumstances where links to local files are secure and desirable. For example, a local process, like a backup job, may want to send execution logs via email that contain links to local files. If the generated email includes "file://" URLs and the email is read in Gmail, the URLs won't even be rendered and even if they were rendered, Chrome (and most other browsers) would block them. Thanks to the Local File Server extension, the process can instead include "http://localhost/" URLs. These will be rendered in all email clients, they won't be blocked by any browser, and the extension will redirect them to the desired local file (provided the URLs are accessed from the machine where the files live).

The syntax for local file URLs is http://localhost/file.html?path= where is the absolute path to the desired local file. No "file://" prefix is allowed in the path. Forward slashes (/) (not backslashes (\)) must be used as directory separators (even on Windows systems). All paths must start with a forward slash (/). Here are a few working examples for different systems:

- Linux: http://localhost/file.html?path=/home/ links to the /home/ directory.

- macOS: http://localhost/file.html?path=/System/ links to the /System/ directory.

- Windows: http://localhost/file.html?path=/C:/Windows/ links to the C:\Windows\ directory.

Malicious third parties could abuse http://localhost/ URLs to access your local files. For that reason, when a http://localhost/file.html?path= URL is clicked, the Local File Server extension doesn't directly open the desired file. Instead, it renders a page that displays a link with a "file:// " URL and a warning to only click on it if one was brought there via a trusted party. If one clicks on the link, the file designated by is opened (provided the link is accessed from the machine where the file lives).