Created
September 18, 2025 08:42
-
-
Save thehappycheese/041a6beeaf296ae19407cd8a88c8844d to your computer and use it in GitHub Desktop.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| /** | |
| * Hash a file without loading the whole thing into memory | |
| * @param {File} file | |
| * @param {"SHA-256"|"SHA-1"} algo | |
| */ | |
| export async function hash_file_in_chunks(file, algo = "SHA-256") { | |
| const chunk_size = 1000 * 1024 * 1024; // 100MB | |
| const count_chunks = Math.ceil(file.size / chunk_size); | |
| const output = new ArrayBuffer(32*count_chunks); | |
| const output_view = new Uint8Array(output); | |
| for ( | |
| let input_offset = 0, output_offset = 0; | |
| input_offset < file.size; | |
| input_offset += chunk_size, output_offset+=32 | |
| ) { | |
| const chunk = file.slice(input_offset, input_offset + chunk_size); | |
| const buffer = await chunk.arrayBuffer(); | |
| const hash_buffer = await crypto.subtle.digest(algo, buffer); | |
| output_view.set(hash_buffer, output_offset); | |
| } | |
| if (count_chunks >1){ | |
| return await crypto.subtle.digest(algo, output); | |
| }else{ | |
| return output | |
| } | |
| } | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment