[1124] - Use Mempool For Fee Rate (#1171)

* Use mempool for fee rate

* Add minor logic change

* Restore carousel items

api/resolvers/chainFee.js

@@ -1,17 +1,16 @@
-import lndService from 'ln-service'
-import lnd from '@/api/lnd'
-
 const cache = new Map()
 const expiresIn = 1000 * 30 // 30 seconds in milliseconds
 
 async function fetchChainFeeRate () {
-  let chainFee = 0
-  try {
-    const fee = await lndService.getChainFeeRate({ lnd })
-    chainFee = fee.tokens_per_vbyte
-  } catch (err) {
+  const url = 'https://mempool.space/api/v1/fees/recommended'
+  const chainFee = await fetch(url)
+    .then((res) => res.json())
+    .then((body) => body.hourFee)
+    .catch((err) => {
       console.error('fetchChainFee', err)
-  }
+      return 0
+    })
+
   cache.set('fee', { fee: chainFee, createdAt: Date.now() })
   return chainFee
 }

components/price.js

@@ -43,39 +43,38 @@ export function PriceProvider ({ price, children }) {
   )
 }
 
+const STORAGE_KEY = 'asSats'
+const DEFAULT_SELECTION = 'fiat'
+
+const carousel = [
+  'fiat',
+  'yep',
+  '1btc',
+  'blockHeight',
+  'chainFee',
+  'halving'
+]
+
 export default function Price ({ className }) {
   const [asSats, setAsSats] = useState(undefined)
+  const [pos, setPos] = useState(0)
+
   useEffect(() => {
-    const satSelection = window.localStorage.getItem('asSats')
-    setAsSats(satSelection ?? 'fiat')
+    const selection = window.localStorage.getItem(STORAGE_KEY) ?? DEFAULT_SELECTION
+    setAsSats(selection)
+    setPos(carousel.findIndex((item) => item === selection))
   }, [])
 
   const { price, fiatSymbol } = usePrice()
   const { height: blockHeight, halving } = useBlockHeight()
   const { fee: chainFee } = useChainFee()
 
-  // Options: yep, 1btc, blockHeight, undefined
-  // yep -> 1btc -> blockHeight -> chainFee -> undefined -> yep
   const handleClick = () => {
-    if (asSats === 'yep') {
-      window.localStorage.setItem('asSats', '1btc')
-      setAsSats('1btc')
-    } else if (asSats === '1btc') {
-      window.localStorage.setItem('asSats', 'blockHeight')
-      setAsSats('blockHeight')
-    } else if (asSats === 'blockHeight') {
-      window.localStorage.setItem('asSats', 'chainFee')
-      setAsSats('chainFee')
-    } else if (asSats === 'chainFee') {
-      window.localStorage.setItem('asSats', 'halving')
-      setAsSats('halving')
-    } else if (asSats === 'halving') {
-      window.localStorage.removeItem('asSats')
-      setAsSats('fiat')
-    } else {
-      window.localStorage.setItem('asSats', 'yep')
-      setAsSats('yep')
-    }
+    const nextPos = (pos + 1) % carousel.length
+
+    window.localStorage.setItem(STORAGE_KEY, carousel[nextPos])
+    setAsSats(carousel[nextPos])
+    setPos(nextPos)
   }
 
   const compClassName = (className || '') + ' text-reset pointer'