add getBalance()

README.md

@@ -1 +1,59 @@
 # Bridge SDK
+
+## Basic usage
+
+Connect station:
+
+```js
+import { StationWallet, ChainType, BridgeType } from 'bridge-sdk'
+
+const wallet = new StationWallet()
+
+if (!wallet.isSupported()) {
+  console.log(
+    `${wallet.description.name} is not supported on your device, please try from a different wallet.`,
+  )
+} else if (!wallet.isInstalled()) {
+  console.log(`You can install ${wallet.description.name} here: ${wallet.description.installLink}`)
+}
+
+wallet
+  .connect(ChainType.terra)
+  .then(({ address }) => console.log(address))
+```
+
+Get the balance (wallet must be already connected):
+```js
+wallet
+  .getBalance('uluna')
+  .then((res) => {
+    res.success
+      ? console.log(`Balance: ${res.data} uluna`)
+      : console.log(`Error: ${res.error}`
+  })
+```
+
+Send tx from station (wallet must be already connected):
+
+```js
+wallet
+  .transfer({
+    src: ChainType.terra,
+    dst: ChainType.osmosis,
+    bridge: BridgeType.ibc,
+    address: 'osmo1...',
+    coin: {
+      amount: 100_000,
+      denom: 'uluna',
+    },
+  })
+  .then((res) => {
+    res.success
+      ? console.log(`TX hash: ${res.txhash}`)
+      : console.log(`Error: ${res.error}`
+  })
+```
+
+> You can use the same functions on the `KeplrWallet` and `MetaMaskWallet` to send a tx from those wallets
+> 
+> You can find more info about the available functions on the [Wallet inteface](/src/wallets/Wallet.ts#25)

package.json

@@ -1,6 +1,6 @@
 {
   "name": "bridge-sdk",
-  "version": "1.0.0",
+  "version": "1.0.0-beta.1",
   "description": "",
   "main": "dist/index.js",
   "typings": "dist/index.d.ts",

src/wallets/Wallet.ts

@@ -22,10 +22,23 @@ export type TxResult =
       error: string
     }
 
+export type QueryResult<T> =
+  | {
+      success: true
+      data: T
+    }
+  | {
+      success: false
+      error: string
+    }
+
 export interface Wallet {
   isSupported(): boolean
   isInstalled(): boolean
   connect(chain: ChainType): Promise<{ address: string }>
+  getBalance(
+    token: string,
+  ): Promise<QueryResult<number>>
   transfer(tx: Tx): Promise<TxResult>
 
   supportedChains: ChainType[]

src/wallets/keplr/KeplrWallet.ts

@@ -2,14 +2,14 @@ import { SigningStargateClient } from '@cosmjs/stargate'
 import { TxRaw } from 'cosmjs-types/cosmos/tx/v1beta1/tx.js'
 import { BridgeType } from '../../const/bridges'
 import { ChainType, chainIDs, ibcChannels } from '../../const/chains'
-import { Tx, TxResult, Wallet } from '../Wallet'
+import { QueryResult, Tx, TxResult, Wallet } from '../Wallet'
 import { getAxelarDepositAddress } from '../../packages/axelar'
 
 type KeplrChain = ChainType.cosmos | ChainType.osmosis
 
 const keplrRpc: Record<KeplrChain, string> = {
-  [ChainType.cosmos]: 'https://rpc-cosmoshub-ia.notional.ventures/',
-  [ChainType.osmosis]: '',
+  [ChainType.cosmos]: 'https://cosmos-mainnet-rpc.allthatnode.com:26657/',
+  [ChainType.osmosis]: 'https://rpc.osmosis.zone/',
 }
 
 declare global {
@@ -21,6 +21,7 @@ declare global {
 export class KeplrWallet implements Wallet {
   private address: string = ''
   private signer: SigningStargateClient | null = null
+  private chain: ChainType | null = null
 
   isSupported(): boolean {
     // supported on chrome, edge and firefox (only on desktop)
@@ -46,6 +47,7 @@ export class KeplrWallet implements Wallet {
     const accounts = await keplrOfflineSigner.getAccounts()
 
     this.address = accounts[0].address
+    this.chain = chain
     this.signer = await SigningStargateClient.connectWithSigner(
       rpc || keplrRpc[chain as KeplrChain],
       keplrOfflineSigner,
@@ -61,17 +63,34 @@ export class KeplrWallet implements Wallet {
     return { address: accounts[0].address }
   }
 
+  async getBalance(
+    token: string,
+  ): Promise<QueryResult<number>> {
+    if (!this.signer) {
+      return {
+        success: false,
+        error: `You must connect the wallet before the query`,
+      }
+    }
+
+    const res = await this.signer.getBalance(this.address, token)
+    return {
+      success: true,
+      data: parseInt(res.amount),
+    }
+  }
+
   async transfer(tx: Tx): Promise<TxResult> {
     if (!this.address || !this.signer) {
       return {
         success: false,
         error: `You must connect the wallet before the transfer`,
       }
     }
-    if (!this.supportedChains.includes(tx.src)) {
+    if (tx.src !== this.chain) {
       return {
         success: false,
-        error: `${tx.src} is not supported by ${this.description.name}`,
+        error: `You must connect to ${tx.src} before the transfer`,
       }
     }
     if (tx.src === tx.dst) {

src/wallets/metamask/MetaMaskWallet.ts

@@ -2,7 +2,7 @@ import MetaMaskOnboarding from '@metamask/onboarding'
 import { BridgeType } from '../../const/bridges'
 import { chainIDs, ChainType } from '../../const/chains'
 import { getAxelarDepositAddress } from '../../packages/axelar'
-import { Tx, TxResult, Wallet } from '../Wallet'
+import { QueryResult, Tx, TxResult, Wallet } from '../Wallet'
 import { ethers } from 'ethers'
 import abi from './abi'
 
@@ -27,6 +27,26 @@ export class MetaMaskWallet implements Wallet {
     return MetaMaskOnboarding.isMetaMaskInstalled()
   }
 
+  async getBalance(
+    token: string,
+  ): Promise<QueryResult<number>> {
+    if (!this.address) {
+      return {
+        success: false,
+        error: `You must connect the wallet before the query`,
+      }
+    }
+
+    const contract = new ethers.Contract(token, abi, window.ethereum)
+
+    const result = await contract.balanceOf(this.address)
+
+    return {
+      success: true,
+      data: result.toNumber(),
+    }
+  }
+
   async connect(chain: ChainType): Promise<{ address: string }> {
     if (!this.supportedChains.includes(chain)) {
       throw new Error(`${chain} is not supported by ${this.description.name}`)

src/wallets/station/StationWallet.ts

@@ -2,12 +2,13 @@ import {
   Coin,
   CreateTxOptions,
   Extension,
+  LCDClient,
   MsgTransfer,
 } from '@terra-money/terra.js'
 import { BridgeType } from '../../const/bridges'
 import { ChainType, ibcChannels } from '../../const/chains'
 import { getAxelarDepositAddress } from '../../packages/axelar'
-import { Tx, TxResult, Wallet } from '../Wallet'
+import { QueryResult, Tx, TxResult, Wallet } from '../Wallet'
 
 const ext = new Extension()
 
@@ -37,6 +38,47 @@ export class StationWallet implements Wallet {
     return res
   }
 
+  async getBalance(
+    token: string,
+  ): Promise<QueryResult<number>> {
+    if (!this.address) {
+      return {
+        success: false,
+        error: `You must connect the wallet before the query`,
+      }
+    }
+
+    const lcd = new LCDClient({
+      URL: 'https://phoenix-lcd.terra.dev',
+      chainID: 'phoenix-1',
+    })
+
+    if (token.startsWith('terra1')) {
+      const result = (await lcd.wasm.contractQuery(token, {
+        balance: {
+          address: this.address,
+        },
+      })) as {
+        data: {
+          balance: string
+        }
+      }
+
+      return {
+        success: true,
+        data: parseInt(result.data.balance),
+      }
+    } else {
+      const result = await lcd.bank.balance(this.address)
+      const coin = result[0].get(token)
+
+      return {
+        success: true,
+        data: coin?.amount?.toNumber() || 0,
+      }
+    }
+  }
+
   async transfer(tx: Tx): Promise<TxResult> {
     if (!this.address) {
       return {
@@ -93,12 +135,18 @@ export class StationWallet implements Wallet {
         }
 
       case BridgeType.axelar:
-        const depositAddress = await getAxelarDepositAddress(tx.address, tx.src, tx.dst, tx.coin.denom)
-
-        if(!depositAddress) return {
-          success: false,
-          error: 'Can\'t generate the Axelar deposit address'
-        }
+        const depositAddress = await getAxelarDepositAddress(
+          tx.address,
+          tx.src,
+          tx.dst,
+          tx.coin.denom,
+        )
+
+        if (!depositAddress)
+          return {
+            success: false,
+            error: "Can't generate the Axelar deposit address",
+          }
 
         const axlTx: CreateTxOptions = {
           msgs: [