Events

Summary
The event pipeline allows developers to easily create real-time applications by letting them listen for important state changes and lifecycle events.
Wildcards
An event name passed to any event emitter method can contain a wildcard (the *character). A wildcard may appear as foo/*, foo/bar/*, or simply *.
* matches one sub-level.
e.g. price/* will trigger on both price/USD_ETH and price/MKR_USD but not price/MKR_USD/foo.
** matches all sub-levels.
e.g. price/** will trigger on price/USD_ETH, price/MKR_USD, and price/MKR_USD/foo.
Event Object
Triggered events will receive the object shown on the right.
<event_type> - the name of the event
<event_payload> - the new state data sent with the event
<event_sequence_number> - a sequentially increasing index
<latest_block_when_emitted> - the current block at the time of the emit
{
    type: <event_type>,
    payload: <event_payload>, /* if applicable */
    index: <event_sequence_number>,
    block: <latest_block_when_emitted>
}
Maker Object
Price
Event Name
Payload
price/ETH_USD
{ price }
price/MKR_USD
{ price }
price/WETH_PETH
{ ratio }
maker.on('price/ETH_USD', eventObj => {
    const { price } = eventObj.payload;
    console.log('ETH price changed to', price);
})
Web3
Event Name
Payload
web3/INITIALIZED
{ provider: { type, url } }
web3/CONNECTED
{ api, network, node }
web3/AUTHENTICATED
{ account }
web3/DEAUTHENTICATED
{ }
web3/DISCONNECTED
{ }
maker.on('web3/AUTHENTICATED', eventObj => {
    const { account } = eventObj.payload;
    console.log('web3 authenticated with account', account);
})
CDP Object
Event Name
Payload
COLLATERAL
{ USD, ETH }
DEBT
{ dai }
cdp.on('DEBT', eventObj => {
    const { dai } = eventObj.payload;
    console.log('Your cdp now has a dai debt of', dai);
})

DSProxy

Using multiple accounts

Last modified 2yr ago

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