ERC20 Utils

package.json

@@ -9,7 +9,7 @@
   "scripts": {
     "build": "bun run --cwd packages/agent-sdk build",
     "lint": "prettier --check packages/**/* && eslint packages/",
-    "format": "prettier --write packages/**/* && eslint packages/ --fix"
+    "fmt": "prettier --write packages/**/* && eslint packages/ --fix"
   },
   "devDependencies": {
     "@types/bun": "latest",

packages/agent-sdk/README.md

@@ -1,4 +1,34 @@
-# agent-sdk
+# Bitte Protocol agent-sdk
+
+This is a TypeScript SDK for building agents on the Bitte Protocol.
+
+## Usage
+
+Define and validate Agent input parameters by example:
+
+Suppose we want to build an agent that transfers an amount of a token to a recipient (i.e. an ERC20 transfer).
+
+```ts
+// Declare Route Input
+interface Input {
+  chainId: number;
+  amount: number;
+  token: string;
+  recipient: Address;
+}
+
+const parsers: FieldParser<Input> = {
+  chainId: numberField,
+  // Note that this is a float (i.e. token units)
+  amount: floatField,
+  token: addressOrSymbolField,
+  recipient: addressField,
+};
+```
+
+Then the route could be implemented as in [examples/erc20transfer.ts](./examples/erc20transfer.ts) - which utilizes other utils from this package.
+
+## Development
 
 To install dependencies:
 

packages/agent-sdk/examples/erc20transfer.ts

@@ -0,0 +1,55 @@
+import { parseUnits, type Address } from "viem";
+import {
+  erc20Transfer,
+  getTokenDecimals,
+  addressField,
+  floatField,
+  numberField,
+  validateInput,
+  type FieldParser,
+} from "../src";
+
+interface Input {
+  chainId: number;
+  amount: number;
+  token: Address;
+  recipient: Address;
+}
+
+const parsers: FieldParser<Input> = {
+  chainId: numberField,
+  // Note that this is a float (i.e. token units)
+  amount: floatField,
+  token: addressField,
+  recipient: addressField,
+};
+
+export async function GET(req: Request): Promise<Response> {
+  const url = new URL(req.url);
+  const search = url.searchParams;
+  console.log("erc20/", search);
+  try {
+    const { chainId, amount, token, recipient } = validateInput<Input>(
+      search,
+      parsers,
+    );
+    const decimals = await getTokenDecimals(chainId, token);
+    return Response.json(
+      {
+        transaction: erc20Transfer({
+          chainId,
+          token,
+          to: recipient,
+          amount: parseUnits(amount.toString(), decimals),
+        }),
+      },
+      { status: 200 },
+    );
+  } catch (error: unknown) {
+    const message =
+      error instanceof Error
+        ? error.message
+        : `Unknown error occurred ${String(error)}`;
+    return Response.json({ ok: false, message }, { status: 400 });
+  }
+}

packages/agent-sdk/package.json

@@ -3,7 +3,12 @@
   "version": "0.0.1",
   "author": "bh2smith",
   "description": "Agent SDK for Bitte Protocol",
-  "keywords": ["bitte", "protocol", "agent", "sdk"],
+  "keywords": [
+    "bitte",
+    "protocol",
+    "agent",
+    "sdk"
+  ],
   "repository": {
     "type": "git",
     "url": "git+https://github.com/bitteprotocol/core.git"

packages/agent-sdk/src/evm/erc20.ts

@@ -0,0 +1,102 @@
+import { erc20Abi } from "viem";
+import { encodeFunctionData, type Address } from "viem";
+import { signRequestFor } from "..";
+import { getClient, type SignRequestData } from "near-safe";
+import type { TokenInfo } from "./types";
+
+const MAX_APPROVAL = BigInt(
+  "115792089237316195423570985008687907853269984665640564039457584007913129639935",
+);
+
+export async function erc20Transfer(params: {
+  chainId: number;
+  token: Address;
+  to: Address;
+  amount: bigint;
+}): Promise<SignRequestData> {
+  const { chainId, token, to, amount } = params;
+  return signRequestFor({
+    chainId,
+    metaTransactions: [
+      {
+        to: token,
+        value: "0x",
+        data: encodeFunctionData({
+          abi: erc20Abi,
+          functionName: "transfer",
+          args: [to, amount],
+        }),
+      },
+    ],
+  });
+}
+
+export async function erc20Approve(params: {
+  chainId: number;
+  token: Address;
+  spender: Address;
+  // If not provided, the maximum amount will be approved.
+  amount?: bigint;
+}): Promise<SignRequestData> {
+  const { chainId, token, spender, amount } = params;
+  return signRequestFor({
+    chainId,
+    metaTransactions: [
+      {
+        to: token,
+        value: "0x",
+        data: encodeFunctionData({
+          abi: erc20Abi,
+          functionName: "approve",
+          args: [spender, amount ?? MAX_APPROVAL],
+        }),
+      },
+    ],
+  });
+}
+
+export async function getTokenInfo(
+  chainId: number,
+  address: Address,
+): Promise<TokenInfo> {
+  const [decimals, symbol] = await Promise.all([
+    getTokenDecimals(chainId, address),
+    getTokenSymbol(chainId, address),
+  ]);
+  return {
+    decimals,
+    symbol,
+  };
+}
+
+export async function getTokenDecimals(
+  chainId: number,
+  address: Address,
+): Promise<number> {
+  const client = getClient(chainId);
+  try {
+    return await client.readContract({
+      address,
+      abi: erc20Abi,
+      functionName: "decimals",
+    });
+  } catch (error: unknown) {
+    throw new Error(`Error fetching token decimals: ${error}`);
+  }
+}
+
+export async function getTokenSymbol(
+  chainId: number,
+  address: Address,
+): Promise<string> {
+  const client = getClient(chainId);
+  try {
+    return await client.readContract({
+      address,
+      abi: erc20Abi,
+      functionName: "symbol",
+    });
+  } catch (error: unknown) {
+    throw new Error(`Error fetching token decimals: ${error}`);
+  }
+}

packages/agent-sdk/src/evm/index.ts

@@ -2,6 +2,9 @@ import type { MetaTransaction, SignRequestData } from "near-safe";
 import { NearSafe } from "near-safe";
 import { getAddress, type Hex, zeroAddress, type Address } from "viem";
 
+export * from "./types";
+export * from "./erc20";
+
 export function signRequestFor({
   from,
   chainId,
@@ -49,11 +52,11 @@ export function createResponse(
 
 export async function validateRequest<
   TRequest extends BaseRequest,
-  TResponse extends BaseResponse
+  TResponse extends BaseResponse,
 >(
   req: TRequest,
   // TODO(bh2smith): Use Bitte Wallet's safeSaltNonce as Default.
-  safeSaltNonce: string
+  safeSaltNonce: string,
 ): Promise<TResponse | null> {
   const metadataHeader = req.headers.get("mb-metadata");
   console.log("Request Metadata:", JSON.stringify(metadataHeader, null, 2));
@@ -69,8 +72,10 @@ export async function validateRequest<
   const derivedSafeAddress = await getAdapterAddress(accountId, safeSaltNonce);
   if (derivedSafeAddress !== getAddress(evmAddress)) {
     return createResponse(
-      { error: `Invalid safeAddress in metadata: ${derivedSafeAddress} !== ${evmAddress}` },
-      { status: 401 }
+      {
+        error: `Invalid safeAddress in metadata: ${derivedSafeAddress} !== ${evmAddress}`,
+      },
+      { status: 401 },
     ) as TResponse;
   }
   console.log(`Valid request for ${accountId} <-> ${evmAddress}`);

packages/agent-sdk/src/evm/types.ts

@@ -0,0 +1,4 @@
+export interface TokenInfo {
+  decimals: number;
+  symbol: string;
+}

packages/agent-sdk/src/index.ts

@@ -1 +1,57 @@
+import { parseUnits, type Address } from "viem";
+import { erc20Transfer, getTokenDecimals } from "./evm";
+import {
+  addressField,
+  floatField,
+  numberField,
+  validateInput,
+  type FieldParser,
+} from "./validate";
+
 export * from "./validate";
+export * from "./evm";
+
+interface Input {
+  chainId: number;
+  amount: number;
+  token: Address;
+  recipient: Address;
+}
+
+const parsers: FieldParser<Input> = {
+  chainId: numberField,
+  // Note that this is a float (i.e. token units)
+  amount: floatField,
+  token: addressField,
+  recipient: addressField,
+};
+
+export async function GET(req: Request): Promise<Response> {
+  const url = new URL(req.url);
+  const search = url.searchParams;
+  console.log("erc20/", search);
+  try {
+    const { chainId, amount, token, recipient } = validateInput<Input>(
+      search,
+      parsers,
+    );
+    const decimals = await getTokenDecimals(chainId, token);
+    return Response.json(
+      {
+        transaction: erc20Transfer({
+          chainId,
+          token,
+          to: recipient,
+          amount: parseUnits(amount.toString(), decimals),
+        }),
+      },
+      { status: 200 },
+    );
+  } catch (error: unknown) {
+    const message =
+      error instanceof Error
+        ? error.message
+        : `Unknown error occurred ${String(error)}`;
+    return Response.json({ ok: false, message }, { status: 400 });
+  }
+}

packages/agent-sdk/tsconfig.json

@@ -30,5 +30,5 @@
     "noPropertyAccessFromIndexSignature": false
   },
   "include": ["src/index.ts", "src/**/*"],
-  "exclude": ["node_modules", "dist"]
+  "exclude": ["node_modules", "dist", "examples"]
 }