add the process to issue asset to README

diff --git a/README.md b/README.md
index 9f50219..2753124 100644 (file)
--- a/README.md
+++ b/README.md
@@ -6,6 +6,10 @@
 
 Cryptographic keys are the primary authorization mechanism on a blockchain.
 
+To create accounts or assets, xpub of keys are required. With this sdk, we can
+`create/delete/list/resetPassword` the key. Please check the api doc if you want
+to operate with keys.
+
 ### Account
 
 An account is an object in Bytom that tracks ownership of assets on a blockchain. 
@@ -43,10 +47,80 @@ const client = new bytom.Client(url)
 
 ## Interaction with bytom
 
-### Acount
+We will walk you through the process to issue some assets.
+
+### Step 1: create a key
+
+```javascript
+const keyPromise = client.keys.create('alias', 'password')
+```
+
+It will create a key whose alias is 'alias' while password is 'password'.
+
+### Step 2: create a account
+
+```javascript
+const accountPromise = keyPromise.then(key => client.accounts.create([key.xpub], 1, 'account'))
+```
+
+### Step 3: create account address
+
+const addressPromise = accountPromise.then(account => {
+  return client.accounts.createReceiverById(account.id)
+})
+
+### Step 4: create asset
+
+```javascript
+const definition = {name: "GOLD", symobol: "GOLD", decimals: 8, description: {}}
+const assetPromise = keyPromise.then(key => {
+  return client.assets.create([key.xpub], 1, 'asset', definition)
+})
+```
+
+### Step 5: issue asset
+
+#### First, build the transaction
+
+```javascript
+const buildPromise = Promise.all([accountPromise, addressPromise, assetPromise]).then(([account, address, asset]) => {
+  const issueAction = {
+    amount: 10000000000,
+    asset_alias: asset.alias,
+    type: 'issue'
+  }
+
+  const gasAction = {
+    type: 'spend_account',
+    account_alias: account.alias,
+    asset_alias: 'BTM',
+    amount: 50000000
+  }
+
+  const controlAction = {
+    type: 'control_address',
+    amount: 10000000000,
+    asset_alias: asset.alias,
+    address: address.address
+  }
+  
+  return client.transactions.build(null, [issueAction, gasAction, controlAction])
+})
+
+```
+
+#### Second, sign the transaction
+
+```javascript
+const signPromise = buildPromise.then(transactionTemplate => {
+  return client.transactions.sign(transactionTemplate, 'password')
+})
+```
+
+#### Finally, submit the signed transaction to the bytom network
 
 ```javascript
-client.account.listAccounts().then(resp => {
-  console.log(resp.data)
+signPromise.then(signed => {
+  return client.transactions.submit(signed.transaction.raw_transaction)
 })
 ```