ABI.Event (abi v1.1.0)
Summary
Functions
Returns the canonical form of this event topic. Pass in indexed: true
to include "indexed" keywords.
Decodes an event, including handling parsing out data from topics.
Returns the signature of an event, i.e. the first item that appears in an Ethereum log for this event.
Functions
Link to this function
canonical(function_selector, opts \\ [])
Returns the canonical form of this event topic. Pass in indexed: true
to include "indexed" keywords.
Examples
iex> ABI.Event.canonical(
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> }
...> )
"Transfer(address,address,uint256)"
iex> ABI.Event.canonical(
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> },
...> names: true
...> )
"Transfer(address from,address to,uint256 amount)"
iex> ABI.Event.canonical(
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> },
...> indexed: true
...> )
"Transfer(address indexed,address indexed,uint256)"
iex> ABI.Event.canonical(
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> },
...> indexed: true,
...> names: true
...> )
"Transfer(address indexed from,address indexed to,uint256 amount)"
Link to this function
decode_event(data, topics, function_selector, opts \\ [])
Decodes an event, including handling parsing out data from topics.
Examples
iex> ABI.Event.decode_event(
...> ~h[0x00000000000000000000000000000000000000000000000000000004a817c800],
...> [
...> ~h[0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef],
...> ~h[0x000000000000000000000000b2b7c1795f19fbc28fda77a95e59edbb8b3709c8],
...> ~h[0x0000000000000000000000007795126b3ae468f44c901287de98594198ce38ea]
...> ],
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> })
{:ok,
"Transfer", %{
"amount" => 20000000000,
"from" => ~h[0xb2b7c1795f19fbc28fda77a95e59edbb8b3709c8],
"to" => ~h[0x7795126b3ae468f44c901287de98594198ce38ea]
}}
iex> ABI.Event.decode_event(
...> ~h[0x00000000000000000000000000000000000000000000000000000004a817c800],
...> [
...> ~h[0x0000000000000000000000000000000000000000000000000000000000000001],
...> ~h[0x000000000000000000000000b2b7c1795f19fbc28fda77a95e59edbb8b3709c8],
...> ~h[0x0000000000000000000000007795126b3ae468f44c901287de98594198ce38ea]
...> ],
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> })
{:error, "Mismatched event signature topic[0], expected=DDF252AD1BE2C89B69C2B068FC378DAA952BA7F163C4A11628F55A4DF523B3EF, got=0000000000000000000000000000000000000000000000000000000000000001"}
iex> ABI.Event.decode_event(
...> ~h[0x00000000000000000000000000000000000000000000000000000004a817c800],
...> [
...> ~h[0x000000000000000000000000b2b7c1795f19fbc28fda77a95e59edbb8b3709c8],
...> ~h[0x0000000000000000000000007795126b3ae468f44c901287de98594198ce38ea]
...> ],
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> })
{:error, "Invalid topics length (got=2, expected=3), consider toggling `check_event_signature`"}
iex> ABI.Event.decode_event(
...> ~h[0x00000000000000000000000000000000000000000000000000000004a817c800],
...> [
...> ~h[0x000000000000000000000000b2b7c1795f19fbc28fda77a95e59edbb8b3709c8],
...> ~h[0x0000000000000000000000007795126b3ae468f44c901287de98594198ce38ea]
...> ],
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> },
...> check_event_signature: false
...> )
{:ok,
"Transfer", %{
"amount" => 20000000000,
"from" => ~h[0xb2b7c1795f19fbc28fda77a95e59edbb8b3709c8],
"to" => ~h[0x7795126b3ae468f44c901287de98594198ce38ea]
}}
Link to this function
event_signature(function_selector)
Returns the signature of an event, i.e. the first item that appears in an Ethereum log for this event.
Examples
iex> ABI.Event.event_signature(
...> %ABI.FunctionSelector{
...> function: "Transfer",
...> types: [
...> %{type: :address, name: "from", indexed: true},
...> %{type: :address, name: "to", indexed: true},
...> %{type: {:uint, 256}, name: "amount"},
...> ]
...> }
...> )
...> |> to_hex()
"0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"