>>115
tickerに関しては俺もそう思ってたけどAPIのドキュメント見たら「subscribe後、最新レートが配信されます。」と書いてある
んでサポートに問い合わせてみたら
lastの更新がない場合でもask,bidどちらかに更新あれば全体的に更新されると返信されたのよ

あとtradesについてはこんな感じ↓
{"channel":"trades","price":"3982589","side":"BUY","size":"0.01","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:27.690Z"}
{"channel":"trades","price":"3982589","side":"SELL","size":"0.01","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:27.690Z"}
{"channel":"trades","price":"3982589","side":"BUY","size":"0.02","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:27.775Z"}
{"channel":"trades","price":"3982589","side":"SELL","size":"0.02","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:27.775Z"}
{"channel":"trades","price":"3982552","side":"BUY","size":"0.03","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:28.416Z"}
{"channel":"trades","price":"3982552","side":"SELL","size":"0.03","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:28.416Z"}
{"channel":"trades","price":"3978562","side":"BUY","size":"0.02","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:28.900Z"}
{"channel":"trades","price":"3978562","side":"SELL","size":"0.02","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:28.900Z"}
{"channel":"trades","price":"3978562","side":"BUY","size":"0.03","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:29.025Z"}
{"channel":"trades","price":"3978562","side":"SELL","size":"0.03","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:29.025Z"}
{"channel":"trades","price":"3978562","side":"BUY","size":"0.03","symbol":"BTC_JPY","timestamp":"2021-01-07T13:18:29.041Z"}
約定したらロング、ショートに関わらず必ずsideが"BUY"と"SELL"で対になってるw

まあ最新レートはorderbooksから取ってきているからいいとしても
取引履歴をわざわざPublicAPIから引っ張るとなるとWebSocketと比較すると遅いからなんだかなあと・・