New ram_actions to transfer ram between accounts

[ericpassmore]

Change Description

Ram Transfer

New RAM system contract action to transfer RAM from one account to another without any fees.

• Charges 0% fee to transfer
• Only uncommited RAM can be transferred
• Notify to & from using require_recipient
• Memo cannot exceed 256 bytes
• returns struct action_return_ramtransfer

Ram Burn

New RAM system contract action to burn RAM from owner account.

• Burned RAM is transferred to eosio.null account
• Should have no impact on RAM Bancor market, RAM supply should remain unchanged
• returns struct action_return_ramtransfer

Ram Logging

Add buy RAM logging by including additional inline actions and notifications via the use of require_recipient.

bytes & quant are computed values based on Bancor algorithm market.

This allows payer or receiver to confirm exact bytes sent/received via notifications.

Buy Ram

• returns struct action_return_buyram

Buy Ram Bytes

• returns struct action_return_buyram

Buy Ram Self

• returns struct action_return_buyram

Sell Ram

• returns struct action_return_sellram

API Changes

• Add require_recipient(receiver) on buyram & buyrambytes actions

ACTION: ramtransfer

• from {name}
• to {name}
• bytes {int64}
• memo {string}

ACTION: ramburn

• owner {name}
• bytes {int64}
• memo {string}

ACTION: logbuyram

/**
 * Logging for buyram & buyrambytes action
 *
 * @param payer - the ram buyer,
 * @param receiver - the ram receiver,
 * @param quantity - the quantity of tokens to buy ram with.
 * @param bytes - the quantity of ram to buy specified in bytes.
 * @param ram_bytes - the ram bytes held by receiver after the action.
 */
[[eosio::action]]
void logbuyram( const name& payer, const name& receiver, const asset& quantity, int64_t bytes, int64_t ram_bytes );

ACTION: buyram buyrambytes buyramself

return struct action_return_buyram

"name": "action_return_buyram",
"base": "",
 "fields": [
                 {
                     "name": "payer",
                     "type": "name"
                 },
                 {
                     "name": "receiver",
                     "type": "name"
                 },
                 {
                     "name": "quantity",
                     "type": "asset"
                 },
                 {
                     "name": "bytes_purchased",
                     "type": "int64"
                 },
                 {
                     "name": "ram_bytes",
                     "type": "int64"
                 }
]

ACTION: ramtransfer ramburn

returns struct action_return_ramtransfer

"name": "action_return_ramtransfer",
"base": "",
"fields": [
            {
               "name": "from",
               "type": "name"
            },
            {
               "name": "to",
               "type": "name"
            },
            {
               "name": "bytes",
               "type": "int64"
            },
            {
               "name": "from_ram_bytes",
               "type": "int64"
            },
            {
               "name": "to_ram_bytes",
               "type": "int64"
            }
]

ACTION: sellram

returns struct action_return_sellram

"name": "action_return_sellram",
"base": "",
"fields": [
                 {
                     "name": "account",
                     "type": "name"
                 },
                 {
                     "name": "quantity",
                     "type": "asset"
                 },
                 {
                     "name": "bytes_sold",
                     "type": "int64"
                 },
                 {
                     "name": "ram_bytes",
                     "type": "int64"
                 }
]

Preconditions

Ram Transfer Preconditions

• from must have sufficient ram_bytes prior to transfer
• from decrease ram_bytes by bytes
• to must exists
• to account can be a contract
• to account can have zero available RAM bytes
• to increase ram_bytes by bytes
• handle ram_managed accounts

Ram Burn Preconditions

• Same conditions as ramtransfer action

Usecases

Ram Transfer Usecases

1. Improves EOS account creation:
   a. Create newaccount using ramtransfer instead of buyram or buyrambytes

2. Improves RAM token wrapper development:
   a. Receive RAM without buy/sell actions (no fees to transferring RAM)
   b. Existing RAM supply can be transferred to existing RAM token wrappers
   c. DeFi composability using memo field

[linh2931]

bytes could be renamed to transferred_bytes in the Reference Contracts. Since this PR is a merge. Don't change it now.

[ericpassmore]

ramburn also returns the action_return_ramtransfer, and for that reason we left the field name as bytes.

[ericpassmore]

Note:start
group: RAM_ACTIONS
category: FEATURES
summary: New ram_actions functions.
Note:end