Add tokens methods

Author: danakt

src/EtherscanApi.ts

@@ -538,4 +538,38 @@ export class EtherscanApi extends EtherscanRequest {
       gas
     })
   }
+
+  /**
+   * Get ERC20-Token TotalSupply by ContractAddress
+   * @param {string} contractAddress
+   * @return {Promise<string>}
+   */
+  public async getTokenByContractAddress(
+    contractAddress: string
+  ): Promise<string> {
+    return this.createRequest({
+      module:          MODULES.STATS,
+      action:          ACTIONS.GET_TOKEN_BY_CONTRACT,
+      contractaddress: contractAddress
+    })
+  }
+
+  /**
+   * Get ERC20-Token Account Balance for TokenContractAddress
+   * @param {string} contractAddress
+   * @return {Promise<string>}
+   */
+  public async getTokenBalanceByContractAddress(
+    contractAddress: string,
+    address: string,
+    tag: string = 'latest'
+  ): Promise<string> {
+    return this.createRequest({
+      module:          MODULES.ACCOUNT,
+      action:          ACTIONS.GET_TOKEN_BALANCE_BY_CONTRACT,
+      contractaddress: contractAddress,
+      address,
+      tag
+    })
+  }
 }

tests/tokens.js

@@ -0,0 +1,22 @@
+const EtherscanAPI = require('../build')
+
+describe('Etherscan tokens methods', () => {
+  const e = new EtherscanAPI()
+
+  test('getTokenByContractAddress', async () => {
+    const data = await e.getTokenByContractAddress(
+      '0x57d90b64a1a57749b0f932f1a3395792e12e7055'
+    )
+
+    expect(isNaN(Number(data))).toBe(false)
+  })
+
+  test('getTokenBalanceByContractAddress', async () => {
+    const data = await e.getTokenBalanceByContractAddress(
+      '0x57d90b64a1a57749b0f932f1a3395792e12e7055',
+      '0xe04f27eb70e025b78871a2ad7eabe85e61212761'
+    )
+
+    expect(isNaN(Number(data))).toBe(false)
+  })
+})