Method toBin

src/cmap/commands.ts:780–806

()

  }

  async toBin(): Promise<Uint8Array[]> {
    const concatenatedOriginalCommandBuffer = ByteUtils.concat(this.command.toBin());
    // otherwise, compress the message
    const messageToBeCompressed = concatenatedOriginalCommandBuffer.slice(MESSAGE_HEADER_SIZE);

    // Extract information needed for OP_COMPRESSED from the uncompressed message
    const originalCommandOpCode = readInt32LE(concatenatedOriginalCommandBuffer, 12);

    // Compress the message body
    const compressedMessage = await compress(this.options, messageToBeCompressed);
    // Create the msgHeader of OP_COMPRESSED
    const msgHeader = ByteUtils.allocate(MESSAGE_HEADER_SIZE);
    NumberUtils.setInt32LE(
      msgHeader,
      0,
      MESSAGE_HEADER_SIZE + COMPRESSION_DETAILS_SIZE + compressedMessage.length
    ); // messageLength
    NumberUtils.setInt32LE(msgHeader, 4, this.command.requestId); // requestID
    NumberUtils.setInt32LE(msgHeader, 8, 0); // responseTo (zero)
    NumberUtils.setInt32LE(msgHeader, 12, OP_COMPRESSED); // opCode
    // Create the compression details of OP_COMPRESSED
    const compressionDetails = ByteUtils.allocate(COMPRESSION_DETAILS_SIZE);
    NumberUtils.setInt32LE(compressionDetails, 0, originalCommandOpCode); // originalOpcode
    NumberUtils.setInt32LE(compressionDetails, 4, messageToBeCompressed.length); // Size of the uncompressed compressedMessage, excluding the MsgHeader
    compressionDetails[8] = Compressor[this.options.agreedCompressor]; // compressorID
    return [msgHeader, compressionDetails, compressedMessage];
  }
}