Multiformats.CID (multiformats_ex v0.2.0)

Handles encoding and decoding CIDs using the multiformats library.

Summary

Types

t()

Functions

decode(cid)

Decodes CID binary string into a CID struct.

encode(content, opts \\ [])

Encodes binary content into a CIDv1 binary string. You control the descriptors and algorithms via the opts Keyword list argument.

encode_v0(content)

Encodes binary content into a CIDv0 binary string. This assumes the type of the content is dag-pb, uses the sha2-256 hashing algorithm, and is base58btc encoded (but without the z prefix).

is_v0?(cid)

Only CIDv0 has an explicit check because all subsequent CID versions are self-describing and therefore you can just pop the version number off the binary string.

Types

t()

@type t() :: %Multiformats.CID{
  cid: binary(),
  content_address: binary(),
  content_type: binary(),
  hash_algorithm: binary(),
  hash_digest: binary(),
  hash_size: non_neg_integer(),
  version: non_neg_integer()
}

Functions

decode(cid)

@spec decode(binary()) :: t()

Decodes CID binary string into a CID struct.

If the CID begins with the identity prefix (0x00), it is assumed to be a CIDv1 string with no multibase encoding.

encode(content, opts \\ [])

@spec encode(binary(), Keyword.t()) :: binary()

Encodes binary content into a CIDv1 binary string. You control the descriptors and algorithms via the opts Keyword list argument.

By default (i.e. when opts is not given), the following values are used by default:

  • :content_type is set to "raw"
  • :hash_algorithm is set to "sha2-256"
  • :base is set to :base32

encode_v0(content)

Encodes binary content into a CIDv0 binary string. This assumes the type of the content is dag-pb, uses the sha2-256 hashing algorithm, and is base58btc encoded (but without the z prefix).

is_v0?(cid)

@spec is_v0?(binary()) :: boolean()

Only CIDv0 has an explicit check because all subsequent CID versions are self-describing and therefore you can just pop the version number off the binary string.