A FRAME-based Substrate node with the Ethereum RPC support, ready for hacking :rocket:
This template was originally forked from the Frontier Node Template. You can find more information on features on this template there, and more detailed usage on the Substrate Developer Hub Tutorials that use this heavily.
To build the chain, execute the following commands from the project root:
$ cargo build --release
To execute the chain, run:
$ ./target/release/aya-node --dev
The node also supports to use manual seal (to produce block manually through RPC).
This is also used by the ts-tests:
$ ./target/release/aya-node --dev --sealing=manual
# Or
$ ./target/release/aya-node --dev --sealing=instant
Optionally, you can build and run the AyA node within Docker directly.
The Dockerfile is optimized for development speed.
(Running the docker run...
command will recompile the binaries but not the dependencies)
Building (takes 5-10 min):
docker build -t aya-node .
Running (takes 1 min to rebuild binaries):
docker run -t aya-node-dev
The development chain spec included with this project defines a genesis
block that has been pre-configured with an EVM account for
Alice. When
a development chain is started,
Alice's EVM account will be funded with a large amount of Ether. The
Polkadot UI can be used to see the details
of Alice's EVM account. In order to view an EVM account, use the Developer
tab of the Polkadot UI
Settings
app to define the EVM Account
type as below. It is also necessary to define the
Address
and LookupSource
to send transaction, and Transaction
and Signature
to be able to
inspect blocks:
{
"Address": "MultiAddress",
"LookupSource": "MultiAddress",
"Account": {
"nonce": "U256",
"balance": "U256"
},
"Transaction": {
"nonce": "U256",
"action": "String",
"gas_price": "u64",
"gas_limit": "u64",
"value": "U256",
"input": "Vec<u8>",
"signature": "Signature"
},
"Signature": {
"v": "u64",
"r": "H256",
"s": "H256"
}
}
Use the Developer
app's RPC calls
tab to query eth > getBalance(address, number)
with Alice's
EVM account ID (0xd43593c715fdd31c61141abd04a99fd6822c8558
); the value that is returned should be:
x: eth.getBalance
340,282,366,920,938,463,463,374,607,431,768,211,455
Further reading: EVM accounts
Alice's EVM account ID was calculated using an included utility script.
The following steps are also available as a Typescript script using Polkadot JS SDK
The truffle
directory contains a
Truffle project that defines
an ERC-20 token. For convenience, this
repository also contains
the compiled bytecode of this token contract,
which can be used to deploy it to the Substrate blockchain.
Further reading: the ERC-20 token standard
Use the Polkadot UI Extrinsics
app to deploy the contract from Alice's account (submit the
extrinsic as a signed transaction) using evm > create
with the following parameters:
source: 0xd43593c715fdd31c61141abd04a99fd6822c8558
init: <raw contract bytecode, a very long hex value>
value: 0
gas_limit: 4294967295
gas_price: 1
nonce: <empty> {None}
The values for gas_limit
and gas_price
were chosen for convenience and have little inherent or
special meaning. Note that None
for the nonce will increment the known nonce for the source
account, starting from 0x0
, you may manually set this but will get an "evm.InvalidNonce" error if
not set correctly.
Once the extrinsic is in a block, navigate to the Network
-> Explorer
tab in the UI, or open up
the browser console to see that the EVM pallet has fired a Created
event with an address
field
that provides the address of the newly-created contract:
# console:
... {"phase":{"applyExtrinsic":2},"event":{"index":"0x0901","data":["0x8a50db1e0f9452cfd91be8dc004ceb11cb08832f"]} ...
# UI:
evm.Created
A contract has been created at given [address]
H160: 0x8a50db1e0f9452cfd91be8dc004ceb11cb08832f
In this case, however, it is trivial to
calculate this value:
0x8a50db1e0f9452cfd91be8dc004ceb11cb08832f
. That is because EVM contract account IDs are
determined solely by the ID and nonce of the contract creator's account and, in this case, both of
those values are well-known (0xd43593c715fdd31c61141abd04a99fd6822c8558
and 0x0
, respectively).
Use the Chain State
UI tab to queryevm > accountCodes
for both Alice's and the contract's
account IDs; notice that Alice's account code is empty and the contract's is equal to the bytecode
of the Solidity contract.
The ERC-20 contract that was deployed inherits from
the OpenZeppelin ERC-20 implementation
and extends its capabilities by adding
a constructor that mints a maximum amount of tokens to the contract creator.
Use the Chain State
app to query evm > accountStorage
and view the value associated with Alice's
account in the _balances
map of the ERC-20 contract; use the ERC-20 contract address
(0x8a50db1e0f9452cfd91be8dc004ceb11cb08832f
) as the first parameter and the storage slot to read
as the second parameter (0x045c0350b9cf0df39c4b40400c965118df2dca5ce0fbcf0de4aafc099aea4a14
). The
value that is returned should be
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
.
The storage slot was calculated using
a provided utility. (Slot 0 and alice address:
0xd43593c715fdd31c61141abd04a99fd6822c8558
)
Further reading: EVM layout of state variables in storage
Use the Developer
-> Extrinsics
tab to invoke the transfer(address, uint256)
function on the
ERC-20 contract with evm > call
and transfer some of the ERC-20 tokens from Alice to Bob.
target: 0x8a50db1e0f9452cfd91be8dc004ceb11cb08832f
source: 0xd43593c715fdd31c61141abd04a99fd6822c8558
input: 0xa9059cbb0000000000000000000000008eaf04151687736326c9fea17e25fc528761369300000000000000000000000000000000000000000000000000000000000000dd
value: 0
gas_limit: 4294967295
gas_price: 1
The value of the input
parameter is an EVM ABI-encoded function call that was calculated using
the Remix web IDE; it consists of a function selector (0xa9059cbb
)
and the arguments to be used for the function invocation. In this case, the arguments correspond to
Bob's EVM account ID (0x8eaf04151687736326c9fea17e25fc5287613693
) and the number of tokens to be
transferred (0xdd
, or 221 in hex).
Further reading: the EVM ABI specification
After the extrinsic has finalized, use the Chain State
app to query evm > accountStorage
to see
the ERC-20 balances for both Alice and Bob.