media_extractor.ts

media_extractor.ts

import { makeTokenizer as makeHTTPTokenizer } from "@tokenizer/http";
import { imageSize } from "image-size";

export class MediaExtractor {
  public async peek(url: string) {
    const CHUNK_SIZE = 1024 * 64; // 64KByte

    try {
      const tokenizer = await makeHTTPTokenizer(url, {
        initialChunkSize: CHUNK_SIZE * 2, // 128 KByte
        minimumChunkSize: CHUNK_SIZE, // 64 KBytes
      });

      const bytesToRead = Math.min(tokenizer.fileInfo.size!, CHUNK_SIZE);
      const buf = Buffer.alloc(bytesToRead, 0x00);

      await tokenizer.peekBuffer(buf);
      await tokenizer.close();

      try {
        const image = imageSize(buf);

        return {
          url,
          resolvedUrl: tokenizer.fileInfo.url,
          size: tokenizer.fileInfo.size,
          type: image.type,
          width: image.width,
          height: image.height,
          orientation: image.orientation,
        };
      } catch (e) {
        // Zero results
        return null;
      }
    } catch (e) {
      return null;
    }
  }
}