chainId

[sparrow313]

const chainId = network.config.chainId

vrfCoordinatorV2Address = networkConfig[chainId]["vrfCoordinatorV2"]

both chainId and vrfCoordinatorV2 are in helper-hardhat.js but why do we import them differently..
in one we write network.config? and networkConfig on the other
why?

[othaime-en]

In the first line const chainId = network.config.chainId we get the chainId of the chain the script was deployed on. In the second line, we use this chainId value to determine what vrfCoordinatorV2 we will use from the group of chainIds that we have in our networkConfig.
So if we deploy our script to rinkeby, this const chainId = network.config.chainId will equate to 4 and this vrfCoordinatorV2Address = networkConfig[chainId]["vrfCoordinatorV2"] will subsequently be vrfCoordinatorV2Address = networkConfig[4]["vrfCoordinatorV2"] which pulls the value of vrfCoordinatorV2 where the chainId was 4 in your networkConfig.

[sparrow313]

so network.config.chainId pulls from the hardhat.confog.js file?

[othaime-en]

No. it takes the chainId of the network itself when we deploy the script.