ex_plasma v0.1.0 ExPlasma.Encoding

Provides the common encoding functionality we use across all the transactions and clients.

Link to this section Summary

Functions

keccak_hash(message)

Produces a KECCAK digest for the message.

merkle_proof(encoded_transactions, txindex)

merkle_root_hash(encoded_transactions)

Generate a Merkle Root hash for the given list of transactions in encoded byte form.

signature_digest(hash_digest, private_key_hash)

Produces a stand-alone, 65 bytes long, signature for message hash.

to_binary(arg)

Converts a hex string into a binary.

to_hex(non_hex)

Converts binary and integer values into its hex string equivalent.

to_int(encoded)

Converts a hex string into the integer value.

Link to this section Types

hash_t()

hash_t() :: <<_::256>>

Link to this section Functions

keccak_hash(message)

keccak_hash(binary()) :: hash_t()

Produces a KECCAK digest for the message.

see https://hexdocs.pm/exth_crypto/ExthCrypto.Hash.html#kec/0

Example

iex> ExPlasma.Encoding.keccak_hash("omg!") <<241, 85, 204, 147, 187, 239, 139, 133, 69, 248, 239, 233, 219, 51, 189, 54,

171, 76, 106, 229, 69, 102, 203, 7, 21, 134, 230, 92, 23, 209, 187, 12>>

merkle_proof(encoded_transactions, txindex)

merkle_proof([binary(), ...], non_neg_integer()) :: binary()

merkle_root_hash(encoded_transactions)

merkle_root_hash([binary(), ...]) :: binary()

Generate a Merkle Root hash for the given list of transactions in encoded byte form.

Examples

iex> encoded_txns = [%ExPlasma.Transaction{} |> ExPlasma.Transaction.encode()] iex> ExPlasma.Encoding.merkle_root_hash(encoded_txns) <<162, 30, 56, 202, 121, 64, 48, 158, 182, 172, 255, 172, 103, 46,

193, 151, 236, 162, 92, 242, 78, 195, 132, 176, 200, 239, 249, 20,
160, 176, 63, 29>>

signature_digest(hash_digest, private_key_hash)

signature_digest(<<_::256>>, <<_::256>>) :: <<_::520>>

Produces a stand-alone, 65 bytes long, signature for message hash.

to_binary(arg)

to_binary(String.t()) :: binary()

Converts a hex string into a binary.

Examples

iex> ExPlasma.Encoding.to_binary "0x1dF62f291b2E969fB0849d99D9Ce41e2F137006e" <<29, 246, 47, 41, 27, 46, 150, 159, 176, 132, 157, 153, 217, 206, 65, 226, 241,

55, 0, 110>>

to_hex(non_hex)

to_hex(binary() | non_neg_integer()) :: String.t()

Converts binary and integer values into its hex string equivalent.

Examples

Convert a raw binary to hex iex> raw = <<29, 246, 47, 41, 27, 46, 150, 159, 176, 132, 157, 153, 217, 206, 65, 226, 241, 55, 0, 110>> iex> ExPlasma.Encoding.to_hex(raw) "0x1df62f291b2e969fb0849d99d9ce41e2f137006e"

Convert an integer to hex iex> ExPlasma.Encoding.to_hex(1) "0x1"

to_int(encoded)

to_int(String.t()) :: non_neg_integer()

Converts a hex string into the integer value.

Examples

# Convert a hex string into an integer iex> ExPlasma.Encoding.to_int("0xb") 11

# Convert a binary into an integer iex> ExPlasma.Encoding.to_int(<<11>>) 11