This commit adds a new add option: "format".
This option specifies how IPFS Cluster is expected to build the DAG when
adding content. By default, it takes a "unixfs", which chunks and DAG-ifies as
it did before, resulting in a UnixFSv1 DAG.
Alternatively, it can be set to "car". In this case, Cluster will directly
read blocks from the CAR file and add them.
Adding CAR files or doing normal processing is independent from letting
cluster do sharding or not. If sharding is ever enabled, Cluster could
potentially shard a large CAR file among peers.
Currently, importing CAR files is limited to a single CAR file with a single
root (the one that is pinned). Future iterations may support multiple CARs
and/or multiple roots by transparently wrapping them.
Usually we had wrap-in-directory enabled by default because otherwise
we had an error when adding single, non-directory files.
wrap-in-directory happens automatically when adding more than one file
so that was no problem. Thigns also worked when adding a folder and Wrap was
disabled. The only case was adding a single with wrap disabled (a default option).
This patches the ipfsadd/add.go file to remember the last added file so that
we can use it's Cid as the resulting root of the adding process without
having to fetch it from our dummy dagservice.
We have to pass this CID to our Finalize() functions, because it turns out that
in this case (single file without wrap-in-directory), the last block added to the DAG
is not the IPFS root (the ipfsadd/Adder adds the mfs root folder last always).
This was the case when wrap-in-directory was enabled by default.
License: MIT
Signed-off-by: Hector Sanjuan <code@hector.link>
This removes a bunch of the channel dance and block forwarding
by having the adder submodules be DAGServices themselves and take
Add() directly from the ipfsAdder.
License: MIT
Signed-off-by: Hector Sanjuan <code@hector.link>