Support for new stake management, with two main targets:
- Switch from a “UTXO based” to an “Account based” model (no more stakeId assigned to each delegation operation, but just a balance assigned to each pair [forger,delegator])
- Allow the possibility to redirect earnings to a smart-contract, which will be responsible for rewards distribution among the delegators.
Notable changes:
-
The old stake native smart contract will be deprecated/deactivated. A new native smart contract will be activated. Methods exposed will allow to:
- Introduce a preliminary mandatory registration step for forgers: will be performed by executing a transaction declaring the forger public keys (VRF key and block sign key), the percentage of rewards to be redirected to a smart contract responsible to manage the delegators’ rewards (named “reward share”), and the address of that smart contract. (The last two fields will be optional). An additional signature will be required with the method to prove the sender is the effective owner of the forger keys: for this reason the preferred way is to use the new http endpoint /transaction/registerForger to invoke the tx based on the local wallet data (it will handle automatically the additional signature). A method is also available in the native smart contract, but currently there is no way to generate a vrf signature from outside the node (it requires the cryptolib, and we don’t have the layer to invoke it from javascript)
- A minimum amount of 10 ZEN will be required to be sent with the transaction: it will be converted automatically into the first stake assigned to the forger.
- The registration step will not be required for existing forgers owning a stake before the hardfork: they will be automatically added to the list of registered ones, with “reward share” = 0 and “smart contract address” = none.
- Introduce an updateForger() method to allow forgers with “reward share” = 0 and “smart contract address” = none to update the fields. The update will be allowed only one time: once set, the values will be immutable. This protects delegators from distribution mechanisms being changed without their knowledge.
- Modify the consensus lottery to consider only forgers owning an amount of stakes (directly or delegated) equals or over to 10 ZEN.
The following changes will happen in the http endpoints:
- /transaction/allForgingStakes and /transaction/myForgingStakes Same format as now, but the output field stakeId will no more be present
- /transaction/makeForgerStake
DEPRECATED (creation of a new stake will be doable only by calling the native smart contract method delegate) - /transaction/spendForgingStake
DEPRECATED (withdraw of a stake will be doable only by calling the native smart contract method withdraw)
The following addition will be included in:
Endpoint: /block/getFeePayments
Rpc endpoint: zen_getFeePayments
Their result will keep the same format as now, but will also include the reward paid to the address of the smart contracts (if defined).
We will also detail the amount coming from the mainchain redistribution: to be retrocompatible they will be into additional fields valueFromMainchain and valueFromFees:
{
"result" : {
"feePayments" : [
{
"address" : "c49dedc85a2c360fea781bcea2bc5d58fde19",
"value" : 2000000 -> total
"valueFromMainchain:": 500000 -> part from the mainchain
"valueFromFees": 1500000 -> part from the fees
}
]
}
}
The maximum ZEN amount redistributed to forgers from the special address 0x000000000000000000003333333333333333333 in a single withdrawal epoch is now limited to a maximum value expressed by the following formula:
-
MAX_VALUE_REDISTRIBUTED = sum [10% of Mainchain’s block-reward Coinbase of each mainchain block reference included in the withdrawal epoch]
-
Funds over the limit will stay in the address balance and will be redistributed in the following epochs.
For example:
Current Mainchain block reward: 6.25 ZEN
Number of mainchain block-reference in a withdrawal epoch: 100
MAX_VALUE_REDISTRIBUTED = 10%(6.25) * 100 = 62.5 ZEN
-
web3_clientVersion now returns also the EON version, in the following format: EON_VERSION/SDK_VERSION/ARCHITECTURE/JAVA_VERSION
-
Better error handling: in case of error the response status code will be 400 instead of 200.
-
In case of batch requests, the response is now always an array, even with a batch composed of only one element. Previously, if the batch request was composed by only one element, the response was an object.
A new endpoint can be optionally exposed (on a different port from the serverAPI) to show some node metrics. To configure it, you can add the following new fragment in the settings file (fragment is optional, the value displayed are the defaults):
metricsApi {
enabled = false
bindAddress = "127.0.0.1:9088"
timeout = 5s
#apiKeyHash = ""
}
Format:
The metrics will be exposed in a http endpoint /metrics, in Prometheus format, one line per metric, in this format:
metric_id value
Available metrics:
Following metrics will be available (also listed in the endpoint /metrics/help):
- block_apply_time
Time to apply block to node wallet and state (milliseconds) - block_apply_time_fromslotstart
Delta between timestamp when block has been applied successfully on this node and start timestamp of the slot it belongs to (milliseconds) - block_applied_ok
Number of received blocks applied successfully (absolute value since start of the node) - block_applied_ko
Number of received blocks not applied (absolute value since start of the node) - mempool_size
Mempool size (number of transactions in this node mempool) - forge_block_count
Number of forged blocks by this node (absolute value since start of the node) - forge_lottery_time
Time to execute the lottery (milliseconds) - forge_blockcreation_time
Time to create a new forged block (calculated from the start timestamp of the slot it belongs to) (milliseconds)
Default value for the property:
maxForgerConnections
Has been increased from 20 to 100. (Remember this only applies if no value is set explicitly in conf / docker env).
Furthermore, the dedicated connection pool for forgers nodes (governed by the above property) now only applies if the node is itself a forger.
Full Changelog file here