Creating a Balancer API provider to fetch pool state for join txs;

.gitignore

@@ -82,4 +82,3 @@ artifacts
 
 #IDE
 .idea
-

README.md

@@ -22,6 +22,88 @@ Testing requires access to an archive node for onchain quote comparisons. This c
 
 `pnpm test`
 
+## Balancer Api Provider
+
+The Balancer API Provider is a provider that facilitates 
+data fetching from the Balancer API,
+it can be used for:
+- Fetch Pool State for Joins;
+- Fetch Pool State for Exits.
+
+### Usage for Joining Pool
+
+```ts
+  import { BalancerApi, PoolJoin } from "@balancer/sdk";
+    ...
+    const joinInput: ProportionalJoinInput = {
+      bptOut,
+      chainId,
+      rpcUrl,
+      kind: JoinKind.Proportional,
+    };
+
+    const balancerApi = new BalancerApi('https://backend-v3-canary.beets-ftm-node.com/graphql', 1);
+    const poolState = await balancerApi.pools.fetchPoolState('0x5f1d6874cb1e7156e79a7563d2b61c6cbce03150000200000000000000000586');
+    const poolJoin = new PoolJoin();
+    const queryResult = await poolJoin.query(joinInput, poolState);
+    const { call, to, value, maxAmountsIn, minBptOut } =
+        poolJoin.buildCall({
+            ...queryResult,
+            slippage,
+            sender: signerAddress,
+            recipient: signerAddress,
+        });
+    const client = createClient({
+      ...
+    })
+
+    await client.sendTransaction({
+      account: signerAddress,
+      chain: client.chain,
+      data: call,
+      to,
+      value,
+    });
+```
+Full working join example: [examples/join/weighted.ts](./examples/join/weighted.ts)
+
+### Usage for Exiting Pool
+```ts
+import { BalancerApi, PoolExit } from "@balancer/sdk";
+...
+const exitInput: SingleAssetExitInput = {
+  chainId,
+  rpcUrl,
+  bptIn,
+  tokenOut,
+  kind: ExitKind.SINGLE_ASSET,
+};
+
+const balancerApi = new BalancerApi('https://backend-v3-canary.beets-ftm-node.com/graphql', 1);
+const poolState = await balancerApi.pools.fetchPoolState('0x5f1d6874cb1e7156e79a7563d2b61c6cbce03150000200000000000000000586');
+const poolExit = new PoolExit();
+const queryResult = await poolExit.query(exitInput, poolState);
+const { call, to, value, maxAmountsIn, minBptOut } =
+  poolExit.buildCall({
+    ...queryResult,
+    slippage,
+    sender: signerAddress,
+    recipient: signerAddress,
+  });
+const client = createClient({
+  ...
+})
+
+await client.sendTransaction({
+  account: signerAddress,
+  chain: client.chain,
+  data: call,
+  to,
+  value,
+});
+```
+Full working exit example: [examples/exit/weighted.ts](./examples/exit/weighted.ts)
+
 ## Anvil client
 To download and install the anvil client, run the following commands (MacOS):
 - `curl -L https://foundry.paradigm.xyz | bash`

examples/exit/weighted.ts

@@ -0,0 +1,92 @@
+import dotenv from 'dotenv';
+dotenv.config();
+
+import { BalancerApi } from "../../src/data/providers/balancer-api";
+import {
+  ChainId,
+  CHAINS, ExitKind, PoolExit, PoolStateInput,
+  SingleAssetExitInput,
+  Slippage,
+  Token,
+  TokenAmount,
+} from "../../src";
+import {
+  Client,
+  createTestClient,
+  http,
+  parseUnits,
+  PublicActions,
+  publicActions,
+  TestActions, WalletActions,
+  walletActions
+} from "viem";
+import { forkSetup, sendTransactionGetBalances } from "../../test/lib/utils/helper";
+
+const balancerApiUrl = 'https://backend-v3-canary.beets-ftm-node.com/graphql';
+const poolId = '0x5c6ee304399dbdb9c8ef030ab642b10820db8f56000200000000000000000014'; // 80BAL-20WETH
+const chainId = ChainId.MAINNET;
+const rpcUrl = 'http://127.0.0.1:8545/';
+const blockNumber = BigInt(18043296);
+const testAddress = '0x10A19e7eE7d7F8a52822f6817de8ea18204F2e4f'; // Balancer DAO Multisig
+const slippage = Slippage.fromPercentage('1'); // 1%
+
+const exit = async () => {
+  const balancerApi = new BalancerApi(balancerApiUrl, 1);
+  const poolState: PoolStateInput = await balancerApi.pools.fetchPoolState(poolId);
+  const client: Client & PublicActions & TestActions & WalletActions = createTestClient({
+    mode: 'hardhat',
+    chain: CHAINS[chainId],
+    transport: http(rpcUrl),
+  })
+    .extend(publicActions)
+    .extend(walletActions);
+  const bpt = new Token(chainId, poolState.address, 18, 'BPT');
+
+  await forkSetup(
+    client,
+    testAddress,
+    [poolState.address],
+    [0], 
+    [
+      parseUnits('100', 18),
+    ],
+    process.env.ETHEREUM_RPC_URL as string,
+    blockNumber,
+  );
+
+  const bptIn = TokenAmount.fromHumanAmount(bpt, '1');
+  const tokenOut = '0xba100000625a3754423978a60c9317c58a424e3D'; // BAL
+
+  const poolExit = new PoolExit();
+
+  const exitInput: SingleAssetExitInput = {
+    chainId,
+    rpcUrl,
+    bptIn,
+    tokenOut,
+    kind: ExitKind.SINGLE_ASSET,
+  };
+
+  const queryResult = await poolExit.query(exitInput, poolState);
+
+  const { call, to, value } =
+    poolExit.buildCall({
+      ...queryResult,
+      slippage,
+      sender: testAddress,
+      recipient: testAddress,
+    });
+  const { transactionReceipt, balanceDeltas } =
+    await sendTransactionGetBalances(
+      [...poolState.tokens.map(({address})=>address), bpt.address],
+      client,
+      testAddress,
+      to,
+      call,
+      value,
+    );
+  console.log(`transaction status: ${transactionReceipt.status}`);
+  console.log(`token amounts deltas per token: ${balanceDeltas}`);
+}
+
+exit();

examples/join/weighted.ts

@@ -0,0 +1,98 @@
+import dotenv from 'dotenv';
+dotenv.config();
+
+import {
+  BalancerApi,
+  ChainId,
+  CHAINS,
+  JoinKind,
+  PoolJoin, PoolStateInput,
+  Slippage,
+  Token,
+  TokenAmount,
+  UnbalancedJoinInput
+} from "../../src";
+import {
+  Client,
+  createTestClient,
+  http,
+  parseUnits,
+  PublicActions,
+  publicActions,
+  TestActions, WalletActions,
+  walletActions
+} from "viem";
+import { forkSetup, sendTransactionGetBalances } from "../../test/lib/utils/helper";
+
+const balancerApiUrl = 'https://backend-v3-canary.beets-ftm-node.com/graphql';
+const poolId = '0x5c6ee304399dbdb9c8ef030ab642b10820db8f56000200000000000000000014'; // 80BAL-20WETH
+const chainId = ChainId.MAINNET;
+const rpcUrl = 'http://127.0.0.1:8545/';
+const blockNumber = BigInt(18043296);
+const testAddress = '0x10A19e7eE7d7F8a52822f6817de8ea18204F2e4f'; // Balancer DAO Multisig
+const slippage = Slippage.fromPercentage('1'); // 1%
+
+const join = async () => {
+  const balancerApi = new BalancerApi(balancerApiUrl, 1);
+  const poolState: PoolStateInput = await balancerApi.pools.fetchPoolState(poolId);
+  const client: Client & PublicActions & TestActions & WalletActions = createTestClient({
+    mode: 'hardhat',
+    chain: CHAINS[chainId],
+    transport: http(rpcUrl),
+  })
+    .extend(publicActions)
+    .extend(walletActions);
+
+  await forkSetup(
+    client,
+    testAddress,
+    [...poolState.tokens.map((t) => t.address), poolState.address],
+    [1,3,0],
+    [
+      ...poolState.tokens.map((t) => parseUnits('100', t.decimals)),
+      parseUnits('100', 18),
+    ],
+    process.env.ETHEREUM_RPC_URL as string,
+    blockNumber,
+  );
+
+
+  const poolJoin = new PoolJoin();
+  const poolTokens = poolState.tokens.map(
+    (t) => new Token(chainId, t.address, t.decimals),
+  );
+  const amountsIn = poolTokens.map((t) =>
+    TokenAmount.fromHumanAmount(t, '1'),
+  );
+
+  // perform join query to get expected bpt out
+  const joinInput: UnbalancedJoinInput = {
+    amountsIn,
+    chainId,
+    rpcUrl,
+    kind: JoinKind.Unbalanced,
+  };
+
+  const queryResult = await poolJoin.query(joinInput, poolState);
+
+  const { call, to, value } =
+    poolJoin.buildCall({
+      ...queryResult,
+      slippage,
+      sender: testAddress,
+      recipient: testAddress,
+    });
+  const { transactionReceipt, balanceDeltas } =
+    await sendTransactionGetBalances(
+      [...poolState.tokens.map(({address})=>address), poolState.address /*BPT*/],
+      client,
+      testAddress,
+      to,
+      call,
+      value,
+    );
+  console.log(`transaction status: ${transactionReceipt.status}`);
+  console.log(`token amounts deltas per token: ${balanceDeltas}`);
+}
+
+join();

package.json

@@ -39,6 +39,7 @@
         "pino-pretty": "^10.0.0",
         "rome": "12.1.3",
         "ts-node": "^10.9.1",
+        "tsconfig-paths": "^4.2.0",
         "tsup": "^6.6.0",
         "typescript": "^5.0.4",
         "vite": "^4.4.2",

src/data/index.ts

@@ -1,3 +1,4 @@
 export * from './enrichers/onChainPoolDataEnricher';
 export * from './providers/subgraphPoolProvider';
+export * from './providers/balancer-api';
 export * from './types';

src/data/providers/balancer-api/client/index.ts

@@ -0,0 +1,31 @@
+import { ChainId } from '../../../../utils';
+
+export class BalancerApiClient {
+    apiUrl: string;
+    chainId: ChainId;
+    constructor(apiUrl: string, chainId: number) {
+        this.apiUrl = apiUrl;
+        this.chainId = chainId;
+    }
+
+    async fetch(
+        operationName: string,
+        query: string,
+        variables: { id: string },
+    ) {
+        const requestQuery = {
+            operationName,
+            query,
+            variables,
+        };
+        const response = await fetch(this.apiUrl, {
+            method: 'post',
+            body: JSON.stringify(requestQuery),
+            headers: {
+                'Content-Type': 'application/json',
+                ChainId: this.chainId.toString(),
+            },
+        });
+        return response.json();
+    }
+}

src/data/providers/balancer-api/index.ts

@@ -0,0 +1,16 @@
+import { Pools } from "./modules/pool-state";
+import { BalancerApiClient } from "./client";
+
+export class BalancerApi {
+
+  balancerApiClient: BalancerApiClient;
+  pools: Pools;
+
+
+  constructor(balancerApiUrl: string, chainId: number){
+    this.balancerApiClient = new BalancerApiClient(balancerApiUrl, chainId);
+    this.pools = new Pools(this.balancerApiClient);
+  }
+
+
+}