Tauri Plugin PLDownloader

A Tauri plugin for cross-platform file downloading with a unified API for Android and iOS. It supports public downloads (visible to users in Photos/Files) and private downloads (stored in app sandbox for internal use or sharing via share sheet).

Platform Support

Features

• Public and private downloads with the same API on Android/iOS
• Auto-detect media (image/video) and save to Photos (iOS) or MediaStore (Android)
• Auto file naming with collision avoidance and extension preservation
• Returns path/URI after download for opening/sharing

Installation

Rust Dependencies

Add to your app Cargo.toml:

[dependencies]
tauri-plugin-pldownloader = "0.1.0"

Or use cargo add:

cargo add tauri-plugin-pldownloader

JavaScript/TypeScript Dependencies

(If you publish a separate guest-js package) install the client API:

npm install tauri-plugin-pldownloader-api
# or
yarn add tauri-plugin-pldownloader-api

Or call commands directly using @tauri-apps/api invoke (see API section).

Usage

Rust Setup

In your app src-tauri/src/lib.rs:

fn main() {
    tauri::Builder::default()
        .plugin(tauri_plugin_pldownloader::init())
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}

JavaScript/TypeScript Usage

If you use helpers from tauri-plugin-pldownloader-api:

import {
  downloadPrivate,
  downloadPublic,
  saveFilePrivateFromBuffer,
  saveFilePublicFromBuffer,
  ping,
  copyFilePath,
} from "tauri-plugin-pldownloader-api";

// Ping
const echo = await ping("hello");

// Private download (stored in sandbox, not visible in Files/Photos)
const r1 = await downloadPrivate({
  url: "https://example.com/file.pdf",
  fileName: "document.pdf", // optional
});
// r1 => { fileName: 'document.pdf', path: '/var/mobile/.../Application Support/Downloads/document.pdf' }

// Public download
// - Media (image/video): save to Photos, return uri = localIdentifier
// - Non-media (pdf, docx, xlsx...): save to Files (On My iPhone > <AppName>)
const r2 = await downloadPublic({
  url: "https://example.com/cat.jpg",
  fileName: "cat.jpg", // optional
  mimeType: "image/jpeg", // optional (helps accurate media detection)
});
// r2 media => { fileName: 'cat.jpg', uri: 'XXXXXXXX-XXXX...' }
// r2 non-media => { fileName: 'report.xlsx', path: '/var/mobile/.../Documents/<AppName>/report.xlsx' }

// Save from ArrayBuffer (for large files, avoids base64 overhead)
const response = await fetch("https://example.com/large-file.zip");
const blob = await response.blob();
const arrayBuffer = await blob.arrayBuffer();

// Save privately from buffer
const r3 = await saveFilePrivateFromBuffer({
  data: arrayBuffer,
  fileName: "large-file.zip",
});
// r3 => { fileName: 'large-file.zip', path: '/var/mobile/.../Application Support/Downloads/large-file.zip' }

// Save publicly from buffer
const r4 = await saveFilePublicFromBuffer({
  data: arrayBuffer,
  fileName: "large-file.zip",
  mimeType: "application/zip", // optional
});
// r4 => { fileName: 'large-file.zip', path: '/var/mobile/.../Documents/<AppName>/large-file.zip' }

// Copy file from A to B (desktop/mobile)
const destPath = await copyFilePath(
  "/path/src/file.pdf",
  "/path/dest/file.pdf"
);

If you want to call invoke yourself:

import { invoke } from "@tauri-apps/api/core";

await invoke("plugin:pldownloader|download_public", {
  payload: { url, fileName, mimeType },
});
await invoke("plugin:pldownloader|download_private", {
  payload: { url, fileName },
});
await invoke("plugin:pldownloader|save_file_public_from_buffer", {
  payload: { data: arrayBuffer, fileName, mimeType },
});
await invoke("plugin:pldownloader|save_file_private_from_buffer", {
  payload: { data: arrayBuffer, fileName },
});

API Reference

TypeScript types

export interface DownloadPrivateRequest {
  url: string;
  fileName?: string;
}

export interface DownloadPublicRequest {
  url: string;
  fileName?: string;
  mimeType?: string;
}

export interface SaveFilePrivateFromBufferRequest {
  data: ArrayBuffer;
  fileName: string;
}

export interface SaveFilePublicFromBufferRequest {
  data: ArrayBuffer;
  fileName: string;
  mimeType?: string;
}

export interface DownloadResponse {
  fileName: string;
  path?: string; // When saved to Files/sandbox
  uri?: string; // When saved to Photos (iOS) or a MediaStore URI (Android if applicable)
}

Commands

• ping(value: string): Promise<string | null>

  • Verify plugin connectivity.

• downloadPrivate(payload: DownloadPrivateRequest): Promise<DownloadResponse>

  • iOS: downloads to Application Support/Downloads (sandbox, not visible in Files/Photos). Returns path.
  • Android: downloads to app private external directory (Downloads or files dir). Returns path.
  • Use cases: store files temporarily for share sheet or internal opening.

• downloadPublic(payload: DownloadPublicRequest): Promise<DownloadResponse>

  • iOS:
    • Media (image/video): saves to Photos via PHPhotoLibrary, returns uri (localIdentifier).
    • Non-media (pdf, docx, xlsx, zip...): saves to Documents/<AppName>/, visible in Files (On My iPhone), returns path.
  • Android:
    • Saves to MediaStore (Downloads/) with mime-type, returns uri.
  • Use cases: download files intended for user visibility and management (Photos/Files/Downloads).

• saveFilePrivateFromBuffer(payload: SaveFilePrivateFromBufferRequest): Promise<DownloadResponse>

  • iOS: saves ArrayBuffer data to Application Support/Downloads (sandbox, not visible in Files/Photos). Returns path.
  • Android: saves ArrayBuffer data to app private external directory (Downloads or files dir). Returns path.
  • Use cases: save large files from memory without base64 overhead, store files temporarily for share sheet or internal opening.

• saveFilePublicFromBuffer(payload: SaveFilePublicFromBufferRequest): Promise<DownloadResponse>

  • iOS:
    • Media (image/video): saves ArrayBuffer data to Photos via PHPhotoLibrary, returns uri (localIdentifier).
    • Non-media (pdf, docx, xlsx, zip...): saves ArrayBuffer data to Documents/<AppName>/, visible in Files (On My iPhone), returns path.
  • Android:
    • Saves ArrayBuffer data to MediaStore (Downloads/) with mime-type, returns uri.
  • Use cases: save large files from memory without base64 overhead, save files intended for user visibility and management (Photos/Files/Downloads).

• copyFilePath(src: string, dest: string): Promise<string>

  • Utility to copy files between known paths (e.g., from sandbox to Documents).

Use Cases

• Save snapshots/exported images: use downloadPublic or saveFilePublicFromBuffer with an image mimeType to save directly to Photos.
• Download documents (PDF, DOCX, XLSX) for users: downloadPublic (non-media) → appears in Files.
• Store internal files to share/open later: downloadPrivate or saveFilePrivateFromBuffer then use the returned path for the share sheet.
• Save large files from memory: use saveFilePublicFromBuffer or saveFilePrivateFromBuffer to avoid base64 encoding overhead when saving ArrayBuffer data.
• Process files in memory: convert Blob to ArrayBuffer, process the data, then save directly without temporary files.

iOS – Info.plist Notes (Required/Recommended)

• Required to save media to Photos:

<key>NSPhotoLibraryAddUsageDescription</key>
<string>We need access to your photo library to save the downloaded file.</string>

• Recommended to make the app folder visible in Files (especially on Simulator):

<key>UIFileSharingEnabled</key>
<true/>
<key>LSSupportsOpeningDocumentsInPlace</key>
<true/>

Android – Notes

• The plugin uses MediaStore to save to public Downloads; no write permission needed on Android 10+.
• On older devices (Android 9 and below), storage permission may be required. For most modern target SDKs, no extra app action is needed if only saving to MediaStore.

Development

Prerequisites

• Rust 1.77.2+
• Tauri 2.7.0+
• Xcode (iOS) / Android Studio (Android)

Building

# Build Rust plugin
cargo build

# Build JavaScript/TypeScript client (if applicable)
yarn build

Testing

# Run Rust tests
cargo test

# Run example app
cd examples/tauri-app
cargo tauri dev

Known Notes

• iOS Photos save error 3302: handled internally by persisting the temp file before calling PHPhotoLibrary. Ensure NSPhotoLibraryAddUsageDescription is present.
• On Simulator, the app folder in Files may be hidden unless the two keys above are present.

Contributing

PRs are welcome!

License

MIT – see LICENSE.