# Objective
The primary motivation behind this PR is to (partially?) address the
limitations imposed by the recently added `AsyncSeek` trait bound
discussed in issue #12880. While the `AsyncSeek` trait add some
flexibility to the reader, it inadvertently restricts the ability to
write asset readers that can truly stream bytes, particularly in
scenarios like HTTP requests where backward seeking is not supported. It
is also challenging in contexts where assets are stored in compressed
formats or require other kinds of transformations.
The logic behind this change is that currently, with `AsyncSeek`, an
asset Reader based on streamed data will either 1) fail silently, 2)
return an error, or 3) use a buffer to satisfy the trait constraint. I
believe that being able to advance in the file without having to "read"
it is a good thing. The only issue here is the ability to seek backward.
It is highly likely that in this context, we only need to seek forward
in the file because we would have already read an entry table upstream
and just want to access one or more resources further in the file. I
understand that in some cases, this may not be applicable, but I think
it is more beneficial not to constrain `Reader`s that want to stream
than to allow "Assets" to read files in a completely arbitrary order.
## Solution
Replace the current `AsyncSeek` trait with `AsyncSeekForward` on asset
`Reader`
## Changelog
- Introduced a new custom trait, `AsyncSeekForward`, for the asset
Reader.
- Replaced the current `AsyncSeek` trait with `AsyncSeekForward` for all
asset `Reader` implementations.
## Migration Guide
Replace all instances of `AsyncSeek` with `AsyncSeekForward` in your
asset reader implementations.
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