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Contract deploy and interact

The AEA erc1155_deploy and erc1155_client skills demonstrate an interaction between two AEAs which use a smart contract.

  • The erc1155_deploy skill deploys the smart contract, creates and mints items.
  • The erc1155_client skill signs a transaction to complete a trustless trade with its counterparty.

Preparation instructions

Dependencies

Follow the Preliminaries and Installation sections from the AEA quick start.

Discussion

The scope of this guide is demonstrating how you can deploy a smart contract and interact with it using AEAs. In this specific demo, you create two AEAs. One deploys and creates tokens inside a smart contract. The other signs a transaction to complete an atomic swap. The smart contract used is ERC1155 with a one-step atomic swap functionality. This means the trade between the two AEAs can be trustless.

Note

This is only for demonstrative purposes since the AEA deploying the contract also has the ability to mint tokens. In reality, the transfer of tokens from the AEA signing the transaction is worthless.

Demo

Create the deployer AEA

Fetch the AEA that will deploy the contract:

aea fetch fetchai/erc1155_deployer:0.29.0
cd erc1155_deployer
aea install
aea build
Alternatively, create from scratch.

Create the AEA that will deploy the contract. 

aea create erc1155_deployer
cd erc1155_deployer
aea add connection fetchai/p2p_libp2p:0.21.0
aea add connection fetchai/soef:0.22.0
aea add connection fetchai/ledger:0.18.0
aea add skill fetchai/erc1155_deploy:0.27.0
aea config set --type dict agent.dependencies \
'{
  "aea-ledger-fetchai": {"version": "<2.0.0,>=1.0.0"},
  "aea-ledger-ethereum": {"version": "<2.0.0,>=1.0.0"},
  "aea-ledger-cosmos": {"version": "<2.0.0,>=1.0.0"}
}'
aea config set agent.default_connection fetchai/p2p_libp2p:0.21.0
aea config set --type dict agent.default_routing \
'{
  "fetchai/contract_api:1.0.0": "fetchai/ledger:0.18.0",
  "fetchai/ledger_api:1.0.0": "fetchai/ledger:0.18.0",
  "fetchai/oef_search:1.0.0": "fetchai/soef:0.22.0"
}'
aea config set --type list vendor.fetchai.connections.p2p_libp2p.cert_requests \
'[{"identifier": "acn", "ledger_id": "ethereum", "not_after": "2022-01-01", "not_before": "2021-01-01", "public_key": "fetchai", "save_path": ".certs/conn_cert.txt"}]'
aea install
aea build
And change the default ledger: 
aea config set agent.default_ledger ethereum

Create a private key for the deployer AEA and add it for Ethereum use:

aea generate-key ethereum
aea add-key ethereum ethereum_private_key.txt

Create a private key for the P2P connection:

aea generate-key fetchai fetchai_connection_private_key.txt
aea add-key fetchai fetchai_connection_private_key.txt --connection

Finally, certify the key for use by the connections that request that:

aea issue-certificates

Create the client AEA

In another terminal, fetch the client AEA which will receive some tokens from the deployer.

aea fetch fetchai/erc1155_client:0.29.0
cd erc1155_client
aea install
aea build
Alternatively, create from scratch.

Create the AEA that will get some tokens from the deployer. 

aea create erc1155_client
cd erc1155_client
aea add connection fetchai/p2p_libp2p:0.21.0
aea add connection fetchai/soef:0.22.0
aea add connection fetchai/ledger:0.18.0
aea add skill fetchai/erc1155_client:0.26.0
aea config set --type dict agent.dependencies \
'{
  "aea-ledger-fetchai": {"version": "<2.0.0,>=1.0.0"},
  "aea-ledger-ethereum": {"version": "<2.0.0,>=1.0.0"},
  "aea-ledger-cosmos": {"version": "<2.0.0,>=1.0.0"}
}'
aea config set agent.default_connection fetchai/p2p_libp2p:0.21.0
aea config set --type dict agent.default_routing \
'{
  "fetchai/contract_api:1.0.0": "fetchai/ledger:0.18.0",
  "fetchai/ledger_api:1.0.0": "fetchai/ledger:0.18.0",
  "fetchai/oef_search:1.0.0": "fetchai/soef:0.22.0"
}'
aea config set --type list vendor.fetchai.connections.p2p_libp2p.cert_requests \
'[{"identifier": "acn", "ledger_id": "ethereum", "not_after": "2022-01-01", "not_before": "2021-01-01", "public_key": "fetchai", "save_path": ".certs/conn_cert.txt"}]'
aea install
aea build
And change the default ledger: 
aea config set agent.default_ledger ethereum

Create a private key for the client AEA and add it for Ethereum use:

aea generate-key ethereum
aea add-key ethereum ethereum_private_key.txt

Create a private key for the P2P connection:

aea generate-key fetchai fetchai_connection_private_key.txt
aea add-key fetchai fetchai_connection_private_key.txt --connection

Finally, certify the key for use by the connections that request that: 

aea issue-certificates

Run Ganache

Execute the following command to run Ganache: 

docker run -p 8545:8545 trufflesuite/ganache-cli:latest --verbose --gasPrice=0 --gasLimit=0x1fffffffffffff --account="$(cat erc1155_deployer/ethereum_private_key.txt),1000000000000000000000" --account="$(cat erc1155_client/ethereum_private_key.txt),1000000000000000000000"

Wait some time for the wealth creation to be mined on Ropsten.

Check your wealth:

aea get-wealth ethereum

You should get 1000000000000000000000.

Note

If no wealth appears after a while, then try funding the private key directly using a web faucet.

Update SOEF configurations for both AEAs

Update the SOEF configuration in both AEA projects: 

aea config set vendor.fetchai.connections.soef.config.chain_identifier ethereum

Run the AEAs

First, run the deployer AEA:

aea run

Once you see a message of the form To join its network use multiaddr 'SOME_ADDRESS' take note of this address.

Alternatively, use aea get-multiaddress fetchai -c -i fetchai/p2p_libp2p:0.21.0 -u public_uri to retrieve the address. The output will be something like /dns4/127.0.0.1/tcp/9000/p2p/16Uiu2HAm2JPsUX1Su59YVDXJQizYkNSe8JCusqRpLeeTbvY76fE5.

This is the entry peer address for the local agent communication network created by the deployer.

This AEA then performs the following steps:

  • deploys the smart contract
  • creates a batch of items in the smart contract
  • mints a batch of items in the smart contract

At some point you should see the log output: 

registering service on SOEF.

At this point, configure the client AEA to connect to the same local ACN created by the deployer by running the following command in the client's terminal, replacing SOME_ADDRESS with the value you noted above: 

aea config set --type dict vendor.fetchai.connections.p2p_libp2p.config \
'{
  "delegate_uri": "127.0.0.1:11001",
  "entry_peers": ["SOME_ADDRESS"],
  "local_uri": "127.0.0.1:9001",
  "log_file": "libp2p_node.log",
  "public_uri": "127.0.0.1:9001"
}'

Then, run the client AEA:

aea run

You will see that after discovery, the two AEAs exchange information about the transaction and the client at the end signs and sends the signature to the deployer AEA to send it to the network.

Note

Transactions on Ropsten can take a significant amount of time! If you run the example a second time, and the previous transaction is still pending, it can lead to a failure. The warning message `Cannot verify whether transaction improves utility. Assuming it does!` can be ignored.

Delete the AEAs

When you're done, stop the agents (CTRL+C), go up a level and delete the AEAs.

cd ..
aea delete erc1155_deployer
aea delete erc1155_client

Communication

This diagram shows the communication between the various entities in this interaction:

sequenceDiagram participant Search participant Erc1155_contract participant Client_AEA participant Deployer_AEA participant Blockchain activate Deployer_AEA activate Search activate Client_AEA activate Erc1155_contract activate Blockchain Deployer_AEA->>Blockchain: deployes smart contract Deployer_AEA->>ERC1155_contract: creates tokens Deployer_AEA->>ERC1155_contract: mint tokens Deployer_AEA->>Search: register_service Client_AEA->>Search: search Search-->>Client_AEA: list_of_agents Client_AEA->>Deployer_AEA: call_for_proposal Deployer_AEA->>Client_AEA: inform_message Client_AEA->>Deployer_AEA: signature Deployer_AEA->>Blockchain: send_transaction Client_AEA->>ERC1155_contract: asks_balance deactivate Deployer_AEA deactivate Search deactivate Client_AEA deactivate ERC1155_contract deactivate Blockchain