Sesame – an xdg-open alternative

When you double click on a file, xdg-open decides what program to use to open it. xdg-open is difficult to configure, inflexible and slow. This is where sesame comes in as an xdg-open alternative.

Sesame is:

• configured with a single JSON file,
• able to have complex rules including regex,
• faster.

By using a single JSON file as a configuration, it's easy to predict which program will be used and easy to change. Not only that but sesame is a single executable that open a single configuration file so it's pretty lightweight.

Sesame's configuration is a bit more powerful than simply choosing a program to use based on a type, it allows you to nest conditions and make smarter decisions. The first condition that passes determines which program is used to open the file. A good example of this is:

• use qutebrowser to open http and https links,
• but use mpv to play youtube videos,
• or use firefox for certain sites.

Expressed as a valid sesame configuration:

{
  "protocol": {
    "http,https": [
      {
        "contains": ["youtube.com/watch?", "youtu.be/watch?"],
        "use": "mpv"
      },
      {
        "contains": ["atlassian.net", "gitlab.com"],
        "use": "firefox"
      },
      "qutebrowser"
    ]
  }
}

Sesame is written in rust and so can be compiled to a static executable (~684 KB) which lets it do its job by using only two files:

• the sesame executable,
• the configuration file.

This is less flexible than the shell script that is often used but makes it faster and easier to understand.