ProtoRune.CBOR (proto_rune v0.3.0)

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Minimal CBOR (RFC 8949) decoder.

Covers the DAG-CBOR subset used by the ATProto event stream: unsigned and negative integers, byte and text strings, arrays, maps, semantic tags, booleans, null and 32/64-bit floats. Indefinite-length items, half floats and simple values are not valid DAG-CBOR and are rejected.

Semantic tags are returned as {:tag, number, value} tuples. The tag 42 (CID link) can be turned into a ProtoRune.CID with ProtoRune.CID.from_link/1.

Decoding returns the value together with the unconsumed rest of the input, which allows decoding the concatenated header/payload pairs used by com.atproto.sync.subscribeRepos frames.

Summary

Types

tag()

A CBOR semantic tag, e.g. {:tag, 42, bytes} for a CID link.

Functions

decode(data)

Decodes a single CBOR item from the head of the given binary.

Types

tag()

@type tag() :: {:tag, non_neg_integer(), term()}

A CBOR semantic tag, e.g. {:tag, 42, bytes} for a CID link.

Functions

decode(data)

@spec decode(binary()) :: {:ok, term(), binary()} | {:error, atom()}

Decodes a single CBOR item from the head of the given binary.

Returns the decoded term and the unconsumed rest of the input.