examples

OMG-JS Examples

Both Alice's and Bob's Ethereum accounts need to have some ETH in them. The ETH is used for gas costs on the rootchain, fees on the childchain and the actual ETH transferred from Alice to Bob. If you want to run the ERC20 examples, make sure the token address is recorded in your .env and either Alice or Bob has a balance on the rootchain.

Running the Examples

To run the examples:

• npm install from root of omg-js.

• npm run build from root of omg-js.

• npm install from /examples directory.

• Create .env file inside the root of the /examples directory with the appropriate values (see /examples/.env.example for example values)

• Refer to below explanation of .env variables

ETH_NODE=                           <entry point to an ethereum node>
WATCHER_URL=                        <url of an informational watcher>
WATCHER_PROXY_URL=                  <*optional* proxy server to catch all watcher requests>
PLASMAFRAMEWORK_CONTRACT_ADDRESS=   <address of the plasma_framework contract>
ERC20_CONTRACT_ADDRESS=             <*optional* address of the erc20 contract that Alice will deposit and transfer to Bob>
ALICE_ETH_ADDRESS=                  <address of Alice's account>
ALICE_ETH_ADDRESS_PRIVATE_KEY=      <Alice's private key>
BOB_ETH_ADDRESS=                    <address of Bob's account>
BOB_ETH_ADDRESS_PRIVATE_KEY=        <Bob's private key>
MILLIS_TO_WAIT_FOR_NEXT_BLOCK=      <interval when checking for block confirmation>
BLOCKS_TO_WAIT_FOR_TXN=             <amount of blocks to wait for confirmation>

Let's run through a story between Alice and Bob. In this story, Alice will first deposit some ETH from the root chain into the child chain. Then Alice will transfer some of that ETH to Bob on the child chain. Bob will then exit his funds from the child chain back into the root chain. His root chain balance will be reflected with the extra ETH that Alice sent to him on the child chain.

Note you can modify the values of the passed flags to suit your needs

Helpful Scripts

From the /examples folder run the following scripts:

• Get Alice's and Bob's balances

  npm run example print-balance -- --owner=alice
npm run example print-balance -- --owner=bob

• Get Alice's and Bob's Childchain UTXOs

  npm run example print-utxos -- --owner=alice
npm run example print-utxos -- --owner=bob

ETH Examples

1. Deposit some ETH from Alice's Rootchain to the Childchain

   npm run example deposit-eth -- --owner=alice --amount=0.01

2. Send some ETH from Alice's Childchain to Bob's Childchain

   npm run example transaction-eth -- --from=alice --to=bob --amount=0.001

Alice has now sent some ETH to Bob. This should be reflected in Bob's childchain balance.

3. Exit one of Bob's Childchain UTXOs to the Rootchain

   npm run example exit-eth -- --owner=bob

Checking Bob's final rootchain balance you will notice it will be a little less than expected. This is because of rootchain gas costs Bob had to pay to exit the childchain.

4. Bob starts and piggyback's an inflight exit for his ouput on a transaction sent by Alice

   npm run example inflight-exit-eth -- --from=alice --to=bob --amount=0.01

ERC20 Examples

Before we begin, we need to deploy and mint some ERC20 tokens. From the examples folder run the following command:

npm run deploy-test-erc20

Use the ERC20 contract address from the output above to configure ERC20_CONTRACT_ADDRESS in your .env file.

Now let's run through the same story above but for ERC20 deposit/transaction/exit.

1. Deposit some ERC20 from Alice's Rootchain to the Childchain

   npm run example deposit-erc20 -- --owner=alice --amount=10

2. Send some ERC20 from Alice's Childchain to Bob's Childchain

   npm run example transaction-erc20 -- --from=alice --to=bob --amount=1

3. Exit one of Bob's Childchain ERC20 UTXOs to the Rootchain

   npm run example exit-erc20 -- --owner=bob