Interface WriteOptions

Append bytes into a path.

Notes

• It always appends content to the end of the file.
• It will create file if the path does not exist.

Set the Cache-Control of op.

Set the chunk of op.

If chunk is set, the data will be chunked by the underlying writer.

NOTE

A service could have their own minimum chunk size while perform write operations like multipart uploads. So the chunk size may be larger than the given buffer size.

Sets concurrent of op.

• By default, OpenDAL writes files sequentially
• When concurrent is set:
  • Multiple write operations can execute in parallel
  • Write operations return immediately without waiting if tasks space are available
  • Close operation ensures all writes complete in order
  • Memory usage increases with concurrency level

Set the Content-Disposition of op.

Set the [Content-Encoding] https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Content-Encoding of op.

Set the Content-Type of op.

Sets if-match condition of op.

This operation provides conditional write functionality based on ETag matching, helping prevent unintended overwrites in concurrent scenarios.

Sets if-none-match condition of op.

This operation provides conditional write functionality based on ETag non-matching, useful for preventing overwriting existing resources or ensuring unique writes.

Sets if_not_exists condition of op.

This operation provides a way to ensure write operations only create new resources without overwriting existing ones, useful for implementing "create if not exists" logic.

Sets user metadata of op.

If chunk is set, the user metadata will be attached to the object during write.

NOTE

• Services may have limitations for user metadata, for example:
  • Key length is typically limited (e.g., 1024 bytes)
  • Value length is typically limited (e.g., 4096 bytes)
  • Total metadata size might be limited
  • Some characters might be forbidden in keys