diff --git a/dev/node/basicSendTx.ts b/dev/node/basicSendTx.ts
new file mode 100644
index 0000000..4e5a833
--- /dev/null
+++ b/dev/node/basicSendTx.ts
@@ -0,0 +1,60 @@
+import { Client, Wallet, Obi, Message, Coin, Transaction, Fee } from '../../lib'
+
+const grpcEndpoint = 'https://laozi-testnet6.bandchain.org/grpc-web'
+const client = new Client(grpcEndpoint)
+
+export async function exampleSendBlockTransaction() {
+  // Step 1: Import a private key for signing transaction
+  const { PrivateKey } = Wallet
+  const mnemonic = 'test'
+  const privateKey = PrivateKey.fromMnemonic(mnemonic)
+  const pubkey = privateKey.toPubkey()
+  const sender = pubkey.toAddress().toAccBech32()
+
+  // Step 2.1: Prepare oracle request's properties
+  const obi = new Obi('{symbols:[string],multiplier:u64}/{rates:[u64]}')
+  const calldata = obi.encodeInput({ symbols: ['ETH'], multiplier: 100 })
+  let coin = new Coin()
+  coin.setDenom('uband')
+  coin.setAmount('1000000')
+
+  let feeCoin = new Coin()
+  feeCoin.setDenom('uband')
+  feeCoin.setAmount('5000')
+
+  // Step 2.2: Create an oracle request message
+  const requestMessage = new Message.MsgRequestData(
+    37,
+    calldata,
+    4,
+    3,
+    'BandProtocol',
+    sender,
+    [coin],
+    50000,
+    200000,
+  )
+
+  // Step 3.1: Construct a transaction
+  const fee = new Fee()
+  fee.setAmountList([feeCoin])
+  fee.setGasLimit(1000000)
+  const chainId = await client.getChainId()
+  const txn = new Transaction()
+  txn.withMessages(requestMessage)
+  await txn.withSender(client, sender)
+  txn.withChainId(chainId)
+  txn.withFee(fee)
+  txn.withMemo('')
+
+  // Step 3.2: Sign the transaction using the private key
+  const signDoc = txn.getSignDoc(pubkey)
+  const signature = privateKey.sign(signDoc)
+
+  const txRawBytes = txn.getTxData(signature, pubkey)
+
+  // Step 4: Broadcast the transaction
+  const sendTx = await client.sendTxBlockMode(txRawBytes)
+
+  return sendTx
+}
diff --git a/dev/node/dataSource.ts b/dev/node/dataSource.ts
new file mode 100644
index 0000000..59ab740
--- /dev/null
+++ b/dev/node/dataSource.ts
@@ -0,0 +1,127 @@
+import { Client, Wallet, Message, Coin, Transaction, Fee } from '../../lib'
+import fs from 'fs'
+import path from 'path'
+
+const grpcEndpoint = 'https://laozi-testnet6.bandchain.org/grpc-web'
+const client = new Client(grpcEndpoint)
+const { PrivateKey } = Wallet
+const mnemonic = 'test'
+const privateKey = PrivateKey.fromMnemonic(mnemonic)
+const pubkey = privateKey.toPubkey()
+const sender = pubkey.toAddress().toAccBech32()
+
+export async function exampleCreateDataSource() {
+  // don't forget to copy this file when you copy the code
+  const execPath = path.resolve(__dirname, './mock/example_data_source.py')
+  const file = fs.readFileSync(execPath, 'utf8')
+  const executable = Buffer.from(file).toString('base64')
+
+  let coin = new Coin()
+  coin.setDenom('uband')
+  coin.setAmount('1000000')
+
+  let feeCoin = new Coin()
+  feeCoin.setDenom('uband')
+  feeCoin.setAmount('5000')
+
+  // Step 2.2: Create an oracle request message
+
+  // name: string
+  // executable: Buffer | string
+  // treasury: string
+  // owner: string
+  // sender: string
+  // feeList: Coin[]
+  // description?: string
+  const requestMessage = new Message.MsgCreateDataSource(
+    'Test DS NodeJs',
+    executable,
+    sender,
+    sender,
+    sender,
+    [feeCoin],
+    'Test DS NodeJs Description',
+  )
+
+  // Step 3.1: Construct a transaction
+  const fee = new Fee()
+  fee.setAmountList([feeCoin])
+  fee.setGasLimit(1000000)
+  const chainId = await client.getChainId()
+  const txn = new Transaction()
+  txn.withMessages(requestMessage)
+  await txn.withSender(client, sender)
+  txn.withChainId(chainId)
+  txn.withFee(fee)
+  txn.withMemo('')
+
+  // Step 3.2: Sign the transaction using the private key
+  const signDoc = txn.getSignDoc(pubkey)
+  const signature = privateKey.sign(signDoc)
+
+  const txRawBytes = txn.getTxData(signature, pubkey)
+
+  // Step 4: Broadcast the transaction
+  const sendTx = await client.sendTxBlockMode(txRawBytes)
+
+  return sendTx
+}
+
+export async function exampleEditDataSource(id: number) {
+  // don't forget to copy this file when you copy the code
+  const execPath = path.resolve(__dirname, './mock/example_data_source.py')
+  const file = fs.readFileSync(execPath, 'utf8')
+  const executable = Buffer.from(file).toString('base64')
+
+  let coin = new Coin()
+  coin.setDenom('uband')
+  coin.setAmount('1000000')
+
+  let feeCoin = new Coin()
+  feeCoin.setDenom('uband')
+  feeCoin.setAmount('5000')
+
+  // Step 2.2: Create an oracle request message
+
+  // dataSourceId: number
+  // treasury: string
+  // owner: string
+  // sender: string
+  // feeList: Coin[]
+  // name: string
+  // description: string
+  // executable: Buffer | string
+  const requestMessage = new Message.MsgEditDataSource(
+    id,
+    sender,
+    sender,
+    sender,
+    [feeCoin],
+    'Test Edit DS NodeJs',
+    'Test Edit DS NodeJs Description',
+    executable,
+  )
+
+  // Step 3.1: Construct a transaction
+  const fee = new Fee()
+  fee.setAmountList([feeCoin])
+  fee.setGasLimit(1000000)
+  const chainId = await client.getChainId()
+  const txn = new Transaction()
+  txn.withMessages(requestMessage)
+  await txn.withSender(client, sender)
+  txn.withChainId(chainId)
+  txn.withFee(fee)
+  txn.withMemo('')
+
+  // Step 3.2: Sign the transaction using the private key
+  const signDoc = txn.getSignDoc(pubkey)
+  const signature = privateKey.sign(signDoc)
+
+  const txRawBytes = txn.getTxData(signature, pubkey)
+
+  // Step 4: Broadcast the transaction
+  const sendTx = await client.sendTxBlockMode(txRawBytes)
+
+  return sendTx
+}
diff --git a/dev/node/getReferenceData.ts b/dev/node/getReferenceData.ts
new file mode 100644
index 0000000..1fe0276
--- /dev/null
+++ b/dev/node/getReferenceData.ts
@@ -0,0 +1,11 @@
+import { Client } from '../../lib'
+
+const grpcEndpoint = 'https://laozi-testnet6.bandchain.org/grpc-web'
+const client = new Client(grpcEndpoint)
+
+// This example demonstrates how to query price data from
+// Band's standard dataset
+export async function exampleGetReferenceData() {
+  const rate = await client.getReferenceData(['BTC/USD', 'ETH/BTC'], 3, 4)
+  return rate
+}
diff --git a/dev/node/index.ts b/dev/node/index.ts
new file mode 100644
index 0000000..92e94d3
--- /dev/null
+++ b/dev/node/index.ts
@@ -0,0 +1,28 @@
+import { exampleCreateDataSource, exampleEditDataSource } from './dataSource'
+import { exampleSendBlockTransaction } from './basicSendTx'
+import { exampleGetReferenceData } from './getReferenceData'
+import {
+  exampleCreateOracleScript,
+  exampleEditOracleScript,
+} from './oracleScript'
+;(async () => {
+  console.log('Creating a new data source...')
+  const responseDS = await exampleCreateDataSource()
+  const rawLogDS = JSON.parse(responseDS.rawLog)
+  const datasourceID = rawLogDS[0].events[0].attributes[0].value
+  console.log(responseDS)
+  console.log('Editing a new data source...')
+  console.log(await exampleEditDataSource(datasourceID))
+  console.log('Test sending an oracle request...')
+  console.log(await exampleSendBlockTransaction())
+  console.log('Test getting reference data...')
+  console.log(await exampleGetReferenceData())
+  console.log('Creating an oracle script...')
+  console.log(await exampleCreateOracleScript())
+  const responseOS = await exampleCreateOracleScript()
+  const rawLogOS = JSON.parse(responseOS.rawLog)
+  const oraclescriptID = rawLogOS[0].events[0].attributes[0].value
+  console.log(responseOS)
+  console.log('Editing an oracle script...')
+  console.log(await exampleEditOracleScript(oraclescriptID))
+})()
diff --git a/dev/node/mock/example_data_source.py b/dev/node/mock/example_data_source.py
new file mode 100644
index 0000000..350e747
--- /dev/null
+++ b/dev/node/mock/example_data_source.py
@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+
+import sys
+import json
+import requests
+
+HEADERS = {"Content-Type": "application/json"}
+
+SYMBOLS_WITH_WEIGHTS = [
+    ["BTC", 0.004909683753206196],
+    ["ETH", 0.13310406316230874],
+    ["BNB", 0.14811355573986523],
+    ["EOS", 8.953653071560828],
+    ["XTZ", 9.094515911727951],
+    ["ATOM", 1.7587624274324516],
+    ["YFI", 0.0010102624194177228],
+    ["BCH", 0.02036657498252182],
+    ["TRX", 205.4816659023913],
+    ["HT", 0.6857067994908471],
+    ["OKB", 0.5980410214630887],
+    ["ZIL", 87.2055371354679],
+    ["CRO", 69.95450022346525],
+    ["XLM", 23.053273306237845],
+    ["ADA", 7.179120672821946],
+    ["DOT", 0.27893252164401366],
+    ["SNX", 0.5011997921585194],
+    ["ALGO", 9.192726225525655],
+    ["OMG", 2.1996607471011007],
+    ["COMP", 0.023306593928026486],
+    ["NEO", 0.19421422582454298],
+    ["VET", 171.95165365836635],
+    ["BAT", 13.126425414588228],
+    ["AAVE", 0.019770547127068678],
+    ["LINK", 0.2764242681323155],
+    ["THETA", 2.176840201683421],
+    ["LEO", 3.5708266638194557],
+    ["KNC", 4.3561169623294544],
+    ["LTC", 0.0413220565629011],
+    ["ZRX", 5.640930140168719],
+    ["XRP", 16.427604258162788],
+    ["MKR", 0.003358561719070429],
+    ["CELO", 1.7828863706544964],
+    ["FTT", 0.5340837373118201],
+    ["BTT", 12062.322952053712],
+    ["REN", 13.314915914819395],
+    ["QTUM", 2.8585514788368362],
+    ["DGB", 62.22667438038412],
+    ["ONT", 3.754157138230833],
+    ["ICX", 2.2741324674258427],
+    ["KSM", 0.01489803116735643],
+    ["UMA", 0.16281776279745758],
+    ["XEM", 5.280971599079332],
+    ["MIOTA", 2.828955811666102],
+]
+
+
+def main(url):
+    symbols, weights = zip(*SYMBOLS_WITH_WEIGHTS)
+    payload = {"symbols": symbols, "min_count": 10, "ask_count": 16}
+    result = requests.request("POST", url, headers=HEADERS, json=payload).json()
+    prices = [float(px["px"]) / float(px["multiplier"]) for px in result["result"]]
+    acc = 0
+    for (p, w) in zip(prices, weights):
+        acc += float(p) * w
+    return acc
+
+
+if __name__ == "__main__":
+    try:
+        print(main(*sys.argv[1:]))
+    except Exception as e:
+        print(str(e), file=sys.stderr)
+        sys.exit(1)
diff --git a/dev/node/mock/example_oracle_script.wasm b/dev/node/mock/example_oracle_script.wasm
new file mode 100644
index 0000000..4b08fb9
Binary files /dev/null and b/dev/node/mock/example_oracle_script.wasm differ
diff --git a/dev/node/mock/standard_dataset_crypto_mainnet.wasm b/dev/node/mock/standard_dataset_crypto_mainnet.wasm
new file mode 100644
index 0000000..9db2508
Binary files /dev/null and b/dev/node/mock/standard_dataset_crypto_mainnet.wasm differ
diff --git a/dev/node/oracleScript.ts b/dev/node/oracleScript.ts
new file mode 100644
index 0000000..9e272bf
--- /dev/null
+++ b/dev/node/oracleScript.ts
@@ -0,0 +1,112 @@
+import { Client, Wallet, Message, Coin, Transaction, Fee } from '../../lib'
+import fs from 'fs'
+import path from 'path'
+
+const grpcEndpoint = 'https://laozi-testnet6.bandchain.org/grpc-web'
+const client = new Client(grpcEndpoint)
+const { PrivateKey } = Wallet
+const mnemonic = 'test'
+const privateKey = PrivateKey.fromMnemonic(mnemonic)
+const pubkey = privateKey.toPubkey()
+const sender = pubkey.toAddress().toAccBech32()
+const owner = 'band18e55d9xyrgyg3tk72zmg7s92uu8sd95jzgj73a'
+
+export async function exampleCreateOracleScript() {
+  // don't forget to copy this file when you copy the code
+  const execPath = path.resolve(
+    __dirname,
+    './mock/standard_dataset_crypto_mainnet.wasm',
+  )
+  const code = fs.readFileSync(execPath)
+
+  let feeCoin = new Coin()
+  feeCoin.setDenom('uband')
+  feeCoin.setAmount('5000')
+
+  // Step 2.2: Create an oracle request message
+
+  // name: string
+  // code: Buffer
+  // owner: string
+  // sender: string
+  // description?: string
+  // schema?: string
+  // sourceCodeUrl?: string
+  const requestMessage = new Message.MsgCreateOracleScript(
+    'Oracle Script Name',
+    code,
+    sender,
+    sender,
+    'Oracle Script Description',
+    '{symbols:[string],multiplier:u64}/{rates:[u64]}',
+    'https://mockurl.com',
+  )
+
+  const fee = new Fee()
+  fee.setAmountList([feeCoin])
+  fee.setGasLimit(1500000)
+  const chainId = await client.getChainId()
+  const txn = new Transaction()
+  txn.withMessages(requestMessage)
+  await txn.withSender(client, sender)
+  txn.withChainId(chainId)
+  txn.withFee(fee)
+  txn.withMemo('')
+
+  const signDoc = txn.getSignDoc(pubkey)
+  const signature = privateKey.sign(signDoc)
+
+  const txRawBytes = txn.getTxData(signature, pubkey)
+  const sendTx = await client.sendTxBlockMode(txRawBytes)
+  return sendTx
+}
+
+export async function exampleEditOracleScript(id: number) {
+  // don't forget to copy this file when you copy the code
+  const execPath = path.resolve(__dirname, './mock/example_oracle_script.wasm')
+  const code = fs.readFileSync(execPath)
+
+  let feeCoin = new Coin()
+  feeCoin.setDenom('uband')
+  feeCoin.setAmount('5000')
+
+  // Step 2.2: Create an oracle request message
+
+  // oracleScriptId: number
+  // owner: string
+  // sender: string
+  // name: string
+  // description: string
+  // schema: string
+  // sourceCodeUrl: string
+  // code: Buffer | string
+  const requestMessage = new Message.MsgEditOracleScript(
+    id,
+    owner,
+    sender,
+    'Edit Oracle Script Name',
+    'Edit Oracle Script Description',
+    '{symbols:[string],multiplier:u64}/{rates:[u64]}',
+    'https://mockurl.com',
+    code,
+  )
+
+  const fee = new Fee()
+  fee.setAmountList([feeCoin])
+  fee.setGasLimit(1500000)
+  const chainId = await client.getChainId()
+  const txn = new Transaction()
+  txn.withMessages(requestMessage)
+  await txn.withSender(client, sender)
+  txn.withChainId(chainId)
+  txn.withFee(fee)
+  txn.withMemo('')
+
+  const signDoc = txn.getSignDoc(pubkey)
+  const signature = privateKey.sign(signDoc)
+
+  const txRawBytes = txn.getTxData(signature, pubkey)
+  const sendTx = await client.sendTxBlockMode(txRawBytes)
+
+  return sendTx
+}