接触Bitshares一段时间后，就经常看到vesting balance这个词，来看看这个是干嘛的。
什么是Vesting Balances？
在Bitshares钱包菜单中有一项是"Vesting balances"，打开看看它的说明，如下：
Vesting balances contain any fees earned through the referral program or from worker pay, for example. They have a certain vesting period and are continually unlocked during that vesting period until all of the balances are available
看起来与公司授予股份类似，这个是授予的资金（可能是worker付费、引荐费用、燃料费用等），但这些资金需要满足一定的条件（到达一定时间等）才能真正提取出来。
都有哪些Vesting Balances？
因为自己帐户没有这项数据，我们直接找个见证人看一下，通过cli_wallet可以取到帐户的vesting balances数据，如下：
unlocked >>> get_vesting_balances fox
get_vesting_balances fox
[{
"id": "1.13.16",
"owner": "1.2.167",
"balance": {
"amount": 5117015,
"asset_id": "1.3.0"
},
"policy": [
1,{
"vesting_seconds": 7776000,
"start_claim": "1970-01-01T00:00:00",
"coin_seconds_earned": "39789908640000",
"coin_seconds_earned_last_update": "2018-06-22T06:00:00"
}
],
"allowed_withdraw": {
"amount": 5117015,
"asset_id": "1.3.0"
},
"allowed_withdraw_time": "2018-06-22T06:57:00"
},{
"id": "1.13.32",
"owner": "1.2.167",
"balance": {
"amount": "8049800000",
"asset_id": "1.3.0"
},
"policy": [
1,{
"vesting_seconds": 86400,
"start_claim": "1970-01-01T00:00:00",
"coin_seconds_earned": "695494080000000",
"coin_seconds_earned_last_update": "2018-06-22T06:57:00"
}
],
"allowed_withdraw": {
"amount": "8049700000",
"asset_id": "1.3.0"
},
"allowed_withdraw_time": "2018-06-22T06:57:00"
}
]
allowed_withdraw就是可以提取的资金，让我先感叹一下好有钱！
相应的数据结构定义为vesting_balance_object，在vesting_balance_object.hpp中可以查看，不再列出。但可以通过代码查一下都有哪些对象使用了vesting_balance，很简单查到有以下几个地方：
account_object
witness_object
worker_object
基本上确定就是帐户的现金返还、见证人工资、工人工资这几项了。
看看"fox"的vesting balances都是哪来的？用get_account fox可以看到，其中一个是cashback，如下：
"cashback_vb": "1.13.16",
用get_witness fox查看，另一项是见证人工资了，如下：
"pay_vb": "1.13.32",
怎么获得Vesting Balances
从上面可知有这几种Vesting Balances，那都有哪些你怎么获得呢？
帐户的cashback
account_object.cpp -> process_fees
d.deposit_cashback(d.get(account.lifetime_referrer), lifetime_cut, require_vesting);
d.deposit_cashback(d.get(account.referrer), referrer_cut, require_vesting);
d.deposit_cashback(d.get(account.registrar), registrar_cut, require_vesting);
在这个函数中有以上几处存取现金返还，终身会员引荐人、引荐人、注册人都有现金返还。
见证人的pay_vb
db_update.cpp
void database::update_signing_witness(const witness_object& signing_witness, const signed_block& new_block)
{
const global_property_object& gpo = get_global_properties();
const dynamic_global_property_object& dpo = get_dynamic_global_properties();
uint64_t new_block_aslot = dpo.current_aslot + get_slot_at_time( new_block.timestamp );
share_type witness_pay = std::min( gpo.parameters.witness_pay_per_block, dpo.witness_budget );
modify( dpo, [&]( dynamic_global_property_object& _dpo )
{
_dpo.witness_budget -= witness_pay;
} );
deposit_witness_pay( signing_witness, witness_pay );
modify( signing_witness, [&]( witness_object& _wit )
{
_wit.last_aslot = new_block_aslot;
_wit.last_confirmed_block_num = new_block.block_num();
} );
}
打包见证人会得到vesting balances
worker balance
db_main.cpp
struct worker_pay_visitor
{
private:
share_type pay;
database& db;
public:
worker_pay_visitor(share_type pay, database& db)
: pay(pay), db(db) {}
typedef void result_type;
template
void operator()(W& worker)const
{
worker.pay_worker(pay, db);
}
};
每个worker类型都有balance对象，通过pay_worker()可以给工人付费。
从以上分析看来，要获得Vesting balances，可以成为其他帐户的推荐人、引荐人、终身引荐人，或者做打包见证人，或者做工人(worker)完成一定工作任务，暂时看大概就这几种途径了。
Vesting Balances相关操作
有两个相关的operation可以操作Vesting Balances，如下：
1、vesting_balance_create_operation
一般情况下会自动创建vesting balance对象，但是也可以手动创建一个vesting balance对象。翻译不好，直接看英文注释...
Manual creation of vesting balances can be used by a stakeholder
to publicly demonstrate that they are committed to the chain.
It can also be used as a building block to create transactions
that function like public debt. Finally, it is useful for
testing vesting balance functionality.
2、vesting_balance_withdraw_operation
提取vesting balance，当然需要满足一定的条件，如下：
void_result vesting_balance_withdraw_evaluator::do_evaluate( const vesting_balance_withdraw_operation& op )
{ try {
const database& d = db();
const time_point_sec now = d.head_block_time();
const vesting_balance_object& vbo = op.vesting_balance( d );
FC_ASSERT( op.owner == vbo.owner, "", ("op.owner", op.owner)("vbo.owner", vbo.owner) );
FC_ASSERT( vbo.is_withdraw_allowed( now, op.amount ), "", ("now", now)("op", op)("vbo", vbo) );
assert( op.amount <= vbo.balance ); // is_withdraw_allowed should fail before this check is reached
/* const account_object& owner_account = */ op.owner( d );
// TODO: Check asset authorizations and withdrawals
return void_result();
} FC_CAPTURE_AND_RETHROW( (op) ) }
这个条件在is_withdraw_allowed()中进行判断，是否到达时间、币数量是否够等。
文章名字都叫基本概念详解，不再细化了，各种费用的具体分配等再研究。
感谢您阅读 @chaimyu 的帖子，期待您能留言交流！
https://steemit.com/bitshares/@chaimyu/bitshares-vesting-balance