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Small library for (de)compressing data with Gzip, which is portable as a WebAssembly module.

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ColinTimBarndt/wasm-gzip

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Wasm-Gzip

Note: Wasm-Gzip was primarily built for the web and might not work with NodeJS.

This small library allows compression and decompression with Gzip using the libflate Rust library. The binary WASM is lightweight (~121 kB WASM + ~2.8 kB JS) which may be useful for compressing network traffic or for web applications that let a user save or load compressed files. Also note that web servers can transfer compressed files, which can half the size of the WASM file.

The source code can be found on GitHub.

Examples

import init, { compress, decompress } from "wasm-gzip";

await init();
const compressed = compress("Hello, World!");
// [31, 139, 8, 0, 0, 0, 0, 0, 0, 3, 5, 192, 49, 13, 0, 0, 8, 3, 65, 43,
// 176, 35, 4, 7, 24, 128, 237, 147, 38, 248, 31, 122, 125, 160, 138, 209,
// 179, 105, 208, 195, 74, 236, 13, 0, 0, 0]
const originalRaw = decompress(compressed);
// [72, 101, 108, 108, 111, 44, 32, 87, 111, 114, 108, 100, 33]
const original = new TextDecoder().decode(originalRaw);
// "Hello, World!"
import init, { compress, decompress } from "wasm-gzip";

await init();
await init(); // can be called multiple times
// The array is *copied* as bytes into WASM memory
const compressed = compress([1, 2, 3, 4]);
// [31, 139, 8, 0, 0, 0, 0, 0, 0, 3, …]
import init, { compress, decompress, freeBuffer } from "wasm-gzip";

await init();
const compressed = compress(10_000, (data) => {
    // *zero-copy* writing into WASM-memory
    // See https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues
    crypto.getRandomValues(data);
});
// Optionally free up memory
freeBuffer();
// `compressed` is no longer safe to access from this point on
import init, { compress, decompress } from "wasm-gzip";

await init();

// A very inefficient way to add strings
const compressed = new Uint8Array(
    (function* () {
        yield* compress("Hello, ");
        yield* compress("World!");
    })(),
);
const combinedRaw = decompress(compressed, { multi: true });
const combined = new TextDecoder().decode(combinedRaw);
// "Hello, World!"

Build Requirements

Before building, run npm install to install all NodeJS dependencies