add mints

schema.graphql

@@ -1,33 +1,41 @@
 type UniswapFactory @entity {
-  # factory address
-  id: ID!
+  id: ID! # factory address, checksummed
   pairCount: Int!
+  txCount: BigInt!
 }
 
 type Token @entity {
-  # token address
-  id: ID!
-
+  id: ID! # token address, lowercased
   decimals: BigInt!
+  txCount: BigInt!
+
+  pairsAsToken0: [Pair!]! @derivedFrom(field: "token0")
+  pairsAsToken1: [Pair!]! @derivedFrom(field: "token1")
+  mintsAsToken0: [Mint!]! @derivedFrom(field: "token0")
+  mintsAsToken1: [Mint!]! @derivedFrom(field: "token1")
 }
 
 type Pair @entity {
-  # pair address
-  id: ID!
-
-  # mirrored from the smart contract
+  id: ID! # pair address, lowercased 
   token0: Token!
   token1: Token!
-
-  # creation stats
   createdAtTimestamp: BigInt!
   createdAtBlockNumber: BigInt!
+  txCount: BigInt!
+
+  mints: [Mint!]! @derivedFrom(field: "pair")
 }
 
-# stores for USD calculations
-type Bundle @entity {
-  # always 1
-  id: ID!
-  ethPrice: BigDecimal! # price of ETH usd
+type Mint @entity {
+  id: ID! # transactionhash#logIndex
+  timestamp: BigInt!
+  blockNumber: BigInt!
+  to: Bytes!
+  pair: Pair!
+  token0: Token!
+  token1: Token!
+  sender: Bytes!
+  amount0: BigDecimal!
+  amount1: BigDecimal!
 }
 

src/mappings/factory.ts

@@ -1,22 +1,18 @@
 /* eslint-disable prefer-const */
-import { Address, log } from '@graphprotocol/graph-ts'
+import { log } from '@graphprotocol/graph-ts'
 
 import { PairCreated } from '../types/Factory/Factory'
-import { Bundle, Pair, Token, UniswapFactory } from '../types/schema'
-import { FACTORY_ADDRESS, fetchTokenDecimals, ZERO_BD } from './helpers'
+import { Pair, Token, UniswapFactory } from '../types/schema'
+import { FACTORY_ADDRESS, fetchTokenDecimals, ZERO_BI } from './helpers'
 
 export function handleNewPair(event: PairCreated): void {
   let factory = UniswapFactory.load(FACTORY_ADDRESS)
   // if it's the first pair, create the factory and the bundle
   if (factory === null) {
     factory = new UniswapFactory(FACTORY_ADDRESS)
     factory.pairCount = 0
+    factory.txCount = ZERO_BI
     factory.save()
-
-    // create new bundle
-    let bundle = new Bundle('1')
-    bundle.ethPrice = ZERO_BD
-    bundle.save()
   }
   factory.pairCount += 1
   factory.save()
@@ -35,6 +31,7 @@ export function handleNewPair(event: PairCreated): void {
     }
 
     token0.decimals = decimals
+    token0.txCount = ZERO_BI
     token0.save()
   }
 
@@ -50,6 +47,7 @@ export function handleNewPair(event: PairCreated): void {
     }
 
     token1.decimals = decimals
+    token1.txCount = ZERO_BI
     token1.save()
   }
 
@@ -58,5 +56,6 @@ export function handleNewPair(event: PairCreated): void {
   pair.token1 = token1.id
   pair.createdAtTimestamp = event.block.timestamp
   pair.createdAtBlockNumber = event.block.number
+  pair.txCount = ZERO_BI
   pair.save()
 }

src/mappings/helpers.ts

@@ -5,7 +5,10 @@ import { ERC20 } from '../types/Factory/ERC20'
 
 export const FACTORY_ADDRESS = '0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f'
 
-export let ZERO_BD = BigDecimal.fromString('0')
+export const ZERO_BD = BigDecimal.fromString('0')
+export const ZERO_BI = BigInt.fromI32(0)
+export const ONE_BD = BigDecimal.fromString('1')
+export const ONE_BI = BigInt.fromI32(1)
 
 export function fetchTokenDecimals(tokenAddress: Address): BigInt | null {
   let contract = ERC20.bind(tokenAddress)
@@ -17,3 +20,18 @@ export function fetchTokenDecimals(tokenAddress: Address): BigInt | null {
   }
   return null
 }
+
+export function exponentToBigDecimal(decimals: BigInt): BigDecimal {
+  let bd = ONE_BD
+  for (let i = ZERO_BI; i.lt(decimals as BigInt); i = i.plus(ONE_BI)) {
+    bd = bd.times(BigDecimal.fromString('10'))
+  }
+  return bd
+}
+
+export function convertTokenToDecimal(tokenAmount: BigInt, exchangeDecimals: BigInt): BigDecimal {
+  if (exchangeDecimals == ZERO_BI) {
+    return tokenAmount.toBigDecimal()
+  }
+  return tokenAmount.toBigDecimal().div(exponentToBigDecimal(exchangeDecimals))
+}

src/mappings/pair.ts

@@ -0,0 +1,49 @@
+import { BigDecimal } from '@graphprotocol/graph-ts'
+import { log } from '@graphprotocol/graph-ts'
+
+import { Mint as MintEntity, Pair, Token, UniswapFactory } from '../types/schema'
+import { Mint } from '../types/templates/Pair/Pair'
+import { convertTokenToDecimal, FACTORY_ADDRESS, ONE_BI } from './helpers'
+
+export function handleMint(event: Mint): void {
+  const block = event.block
+  const transaction = event.transaction
+  const mintId = transaction.hash.toHex() + '#' + event.logIndex.toString()
+
+  const transactionTo = transaction.to
+
+  if (transactionTo === null) {
+    log.warning('Could not fetch transaction to address, skipping mint {}.', [mintId])
+    return
+  }
+
+  const uniswap = UniswapFactory.load(FACTORY_ADDRESS)!
+  const pair = Pair.load(event.address.toHex())!
+  const token0 = Token.load(pair.token0)!
+  const token1 = Token.load(pair.token1)!
+
+  const token0Amount = convertTokenToDecimal(event.params.amount0, token0.decimals)
+  const token1Amount = convertTokenToDecimal(event.params.amount1, token1.decimals)
+
+  token0.txCount = token0.txCount.plus(ONE_BI)
+  token1.txCount = token1.txCount.plus(ONE_BI)
+  pair.txCount = pair.txCount.plus(ONE_BI)
+  uniswap.txCount = uniswap.txCount.plus(ONE_BI)
+
+  token0.save()
+  token1.save()
+  pair.save()
+  uniswap.save()
+
+  const mint = new MintEntity(mintId)
+  mint.timestamp = block.timestamp
+  mint.blockNumber = block.number
+  mint.to = transactionTo
+  mint.pair = pair.id
+  mint.token0 = token0.id
+  mint.token1 = token1.id
+  mint.sender = event.params.sender
+  mint.amount0 = token0Amount as BigDecimal
+  mint.amount1 = token1Amount as BigDecimal
+  mint.save()
+}

subgraph.yaml

@@ -30,4 +30,26 @@ dataSources:
           file: ./abis/ERC20NameBytes.json
       eventHandlers:
         - event: PairCreated(indexed address,indexed address,address,uint256)
-          handler: handleNewPair
+          handler: handleNewPair
+templates:
+  - kind: ethereum/contract
+    name: Pair
+    network: mainnet
+    source:
+      abi: Pair
+    mapping:
+      kind: ethereum/events
+      apiVersion: 0.0.9
+      language: wasm/assemblyscript
+      file: ./src/mappings/pair.ts
+      entities:
+        - Pair
+        - Token
+      abis:
+        - name: Pair
+          file: ./abis/pair.json
+        - name: Factory
+          file: ./abis/factory.json
+      eventHandlers:
+        - event: Mint(indexed address,uint256,uint256)
+          handler: handleMint