Remove PoW consensus

Author: Seulgi Kim

Cargo.lock

@@ -19,7 +19,6 @@ codechain-types = { path = "../types" }
 codechain-stratum = { path = "../stratum" }
 codechain-vm = { path = "../vm" }
 crossbeam-channel = "0.3"
-cuckoo = { git = "https://github.com/CodeChain-io/rust-cuckoo.git", rev = "280cab9c" }
 hashdb = { path = "../util/hashdb" }
 hyper = { git = "https://github.com/paritytech/hyper", default-features = false }
 journaldb = { path = "../util/journaldb" }

core/Cargo.toml

@@ -375,19 +375,11 @@ impl LockedBlock {
     /// Provide a valid seal in order to turn this into a `SealedBlock`.
     /// This does check the validity of `seal` with the engine.
     /// Returns the `ClosedBlock` back again if the seal is no good.
-    pub fn try_seal(
-        mut self,
-        engine: &dyn CodeChainEngine,
-        seal: Vec<Bytes>,
-    ) -> Result<SealedBlock, (Error, LockedBlock)> {
+    pub fn seal_block(mut self, seal: Vec<Bytes>) -> SealedBlock {
         self.block.header.set_seal(seal);
 
-        // TODO: passing state context to avoid engines owning it?
-        match engine.verify_local_seal(&self.block.header) {
-            Err(e) => Err((e, self)),
-            _ => Ok(SealedBlock {
-                block: self.block,
-            }),
+        SealedBlock {
+            block: self.block,
         }
     }
 

core/res/blake_pow.json

@@ -316,21 +316,13 @@ impl Client {
     }
 }
 
-/// When RESEAL_MAX_TIMER invoked, a block is created although the block is empty.
-const RESEAL_MAX_TIMER_TOKEN: TimerToken = 0;
 /// The minimum time between blocks, the miner creates a block when RESEAL_MIN_TIMER is invoked.
 /// Do not create a block before RESEAL_MIN_TIMER event.
 const RESEAL_MIN_TIMER_TOKEN: TimerToken = 1;
 
 impl TimeoutHandler for Client {
     fn on_timeout(&self, token: TimerToken) {
         match token {
-            RESEAL_MAX_TIMER_TOKEN => {
-                // Working in PoW only
-                if self.engine().seals_internally().is_none() && !self.importer.miner.prepare_work_sealing(self) {
-                    self.update_sealing(BlockId::Latest, true);
-                }
-            }
             RESEAL_MIN_TIMER_TOKEN => {
                 // Checking self.ready_transactions() for efficiency
                 if !self.engine().engine_type().ignore_reseal_min_period() && !self.is_pending_queue_empty() {
@@ -691,20 +683,6 @@ impl ImportBlock for Client {
             Err(err) => unreachable!("Reseal min timer should not fail but failed with {:?}", err),
         }
     }
-
-    fn set_max_timer(&self) {
-        self.reseal_timer.cancel(RESEAL_MAX_TIMER_TOKEN).expect("Reseal max timer clear succeeds");
-        match self
-            .reseal_timer
-            .schedule_once(self.importer.miner.get_options().reseal_max_period, RESEAL_MAX_TIMER_TOKEN)
-        {
-            Ok(_) => {}
-            Err(TimerScheduleError::TokenAlreadyScheduled) => {
-                // Since set_max_timer could be called in multi thread, ignore the TokenAlreadyScheduled error
-            }
-            Err(err) => unreachable!("Reseal max timer should not fail but failed with {:?}", err),
-        }
-    }
 }
 
 

core/res/cuckoo.json

@@ -206,8 +206,6 @@ pub trait ImportBlock {
 
     /// Set reseal min timer as reseal_min_period, for creating blocks with transactions which are pending because of reseal_min_period
     fn set_min_timer(&self);
-    /// Set reseal max timer as reseal_max_period, for creating empty blocks every reseal_max_period
-    fn set_max_timer(&self);
 }
 
 /// Blockchain database client. Owns and manages a blockchain and a block queue.

core/res/husky.json

@@ -514,8 +514,6 @@ impl ImportBlock for TestBlockChainClient {
     }
 
     fn set_min_timer(&self) {}
-
-    fn set_max_timer(&self) {}
 }