/
cid.go
44 lines (37 loc) · 947 Bytes
/
cid.go
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package cbor
import (
"github.com/ipfs/go-cid"
cbornode "github.com/ipfs/go-ipld-cbor"
"github.com/polydawn/refmt/obj/atlas"
)
var cidAtlasEntry = atlas.BuildEntry(cid.Cid{}).
UseTag(cbornode.CBORTagLink).
Transform().
TransformMarshal(atlas.MakeMarshalTransformFunc(
castCidToBytes,
)).
TransformUnmarshal(atlas.MakeUnmarshalTransformFunc(
castBytesToCid,
)).
Complete()
func castBytesToCid(x []byte) (cid.Cid, error) {
if len(x) == 0 {
return cid.Cid{}, cbornode.ErrEmptyLink
}
// TODO: manually doing multibase checking here since our deps don't
// support binary multibase yet
if x[0] != 0 {
return cid.Cid{}, cbornode.ErrInvalidMultibase
}
c, err := cid.Cast(x[1:])
if err != nil {
return cid.Cid{}, cbornode.ErrInvalidLink
}
return c, nil
}
func castCidToBytes(link cid.Cid) ([]byte, error) {
if !link.Defined() {
return nil, cbornode.ErrEmptyLink
}
return append([]byte{0}, link.Bytes()...), nil
}