user-data

tauri-plugin-user-data#

Returns who is signed in and how they look: the account name, the full name, the profile picture already encoded as a data URI and the home directory. It is what draws the face and the name in the desktop panel.

• Crate: tauri-plugin-user-data
• JS package: @vasakgroup/plugin-user-data
• Platform: Linux on the desktop (reads passwd, getent and /var/lib/AccountsService)

Installation#

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# src-tauri/Cargo.toml
[dependencies]
tauri-plugin-user-data = "2.1.1"

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bun add @vasakgroup/plugin-user-data

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// src-tauri/src/lib.rs
fn main() {
    tauri::Builder::default()
        .plugin(tauri_plugin_user_data::init())
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}

init takes no arguments. The plugin queries the system on every call, so there is nothing to configure or keep in sync.

Permissions#

user-data:default, in the capabilities file:

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// src-tauri/capabilities/default.json
{
  "permissions": ["user-data:default"]
}

The default permission enables the plugin’s only command. There are also user-data:allow-get-user-info and user-data:deny-get-user-info on their own, which is what the default permission includes.

JavaScript API#

getUserData(): Promise<UserInfo | null>#

Returns the data of the session account, or null when the backend answered nothing. The object carries:

• username — The account name (pato). There is always one.
• full_name — The full name (Joaquin Decima). If the account has none, it is the account name itself.
• avatar_data — The picture as a data URI (data:image/png;base64,…), ready for an <img src>. It is never empty: when there is no usable picture, a generic icon arrives.
• home_dir — The home directory (/home/pato).

The UserInfo interface the package exports declares username, full_name and avatar_data; home_dir travels in the response all the same.

Rust commands#

• get_user_info() — The account name, the full name, the picture as a data URI and the home directory.

Example#

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<script setup lang="ts">
import { onMounted, ref } from "vue";
import { getUserData, type UserInfo } from "@vasakgroup/plugin-user-data";

const account = ref<UserInfo | null>(null);

onMounted(async () => {
  account.value = await getUserData();
});
</script>

<template>
  <img v-if="account" :src="account.avatar_data" :alt="account.full_name" />
  <p v-if="account">{{ account.full_name }}</p>
</template>

Implementation details#

• It never fails because of an incomplete environment. The command always returns usable data: without USER, without passwd or without HOME there is still a username, a full name and a directory.
• The account name comes from USER; if it is missing, from passwd by uid (getpwuid); and if that fails too, from the uid as a number. An application launched from a systemd unit may not have USER, and that is where it used to fail.
• The full name is the fifth field of getent passwd <account> (GECOS), cut at the first comma: Joaquin Decima,Oficina 3,555-1234 becomes Joaquin Decima. When it is empty, the account name is used.
• The home directory is the sixth field of that same line, with HOME as a fallback.
• The picture is looked up in order: ~/.face, ~/.face.icon, /var/lib/AccountsService/icons/<account> and /usr/share/icons/default/user.png. The first one that exists and is a drawable image wins.
• The type is detected from the content, not from the extension: PNG, JPEG, GIF, BMP, WebP and SVG. Two of the four paths have no extension, and going by the name a JPEG .face was declared PNG and was not drawn.
• A 4 MiB cap per picture. The image travels to the WebView as base64, inside a single IPC message, so a huge file is skipped instead of loaded. The cap is applied while reading, not only while measuring the file.
• An unreadable, empty or non-image file is skipped and the next path is tried: the system picture is better than a hole left by a broken file.
• No fallback picture means no hole: the plugin ships an embedded generic SVG and returns it when no path worked. It lives inside the binary, not as a path to a theme file that may not be there.
• No events: the plugin emits none. Anyone who wants fresh data calls getUserData() again, which queries the system every time.