The pages http://www.kittyexplorer.com/prices/ and https://kittysales.herokuapp.com/ show sales with prices and the IDs of the cats sold. How could I implement such a functionality programmatically?
I've already searched GitHub but the code there does not allow to access such a sales history. I've also looked at the transaction details at https://etherscan.io/ but I do not get information about the cat ID there.
http://web3js.readthedocs.io/en/1.0/web3-eth-contract.html#getpastevents
The kitty auction contract emits an "AuctionSuccessful" event on each successful sale. You can get past events using web3.js with code that looks something like:
var cksale = web3.eth.contract(saleAbi).at("0xb1690C08E213a35Ed9bAb7B318DE14420FB57d8C")
cksale.getPastEvents('AuctionSuccessful', { fromBlock: 4605167 }, (error, events)=>{
console.log(`Got some sales: ${JSON.stringify(events)}`)
})
Note: Cryptokitties was deployed on block 4605167 so no point in checking blocks earlier than that for events.
It takes a while to search for past events, you'll probably be better off chunking it into 10/100 block intervals instead of trying to get all events in one giant call.
