chore: force require anchor blocks

Author: jcnelson

stackslib/src/chainstate/coordinator/mod.rs

@@ -198,6 +198,9 @@ pub trait BlockEventDispatcher {
 }
 
 pub struct ChainsCoordinatorConfig {
+    /// true: assume all anchor blocks are present, and block chain sync until they arrive
+    /// false: process sortitions in reward cycles without anchor blocks
+    pub assume_present_anchor_blocks: bool,
     /// true: use affirmation maps before 2.1
     /// false: only use affirmation maps in 2.1 or later
     pub always_use_affirmation_maps: bool,
@@ -209,8 +212,9 @@ pub struct ChainsCoordinatorConfig {
 impl ChainsCoordinatorConfig {
     pub fn new() -> ChainsCoordinatorConfig {
         ChainsCoordinatorConfig {
-            always_use_affirmation_maps: false,
+            always_use_affirmation_maps: true,
             require_affirmed_anchor_blocks: true,
+            assume_present_anchor_blocks: true,
         }
     }
 }
@@ -2336,6 +2340,20 @@ impl<
                     panic!("BUG: no epoch defined at height {}", header.block_height)
                 });
 
+        if self.config.assume_present_anchor_blocks {
+            // anchor blocks are always assumed to be present in the chain history,
+            // so report its absence if we don't have it.
+            if let PoxAnchorBlockStatus::SelectedAndUnknown(missing_anchor_block, _) =
+                &rc_info.anchor_status
+            {
+                info!(
+                    "Currently missing PoX anchor block {}, which is assumed to be present",
+                    &missing_anchor_block
+                );
+                return Ok(Some(missing_anchor_block.clone()));
+            }
+        }
+
         if cur_epoch.epoch_id >= StacksEpochId::Epoch21 || self.config.always_use_affirmation_maps {
             // potentially have an anchor block, but only process the next reward cycle (and
             // subsequent reward cycles) with it if the prepare-phase block-commits affirm its

testnet/stacks-node/src/config.rs

@@ -1638,6 +1638,7 @@ pub struct NodeConfig {
     pub use_test_genesis_chainstate: Option<bool>,
     pub always_use_affirmation_maps: bool,
     pub require_affirmed_anchor_blocks: bool,
+    pub assume_present_anchor_blocks: bool,
     /// Fault injection for failing to push blocks
     pub fault_injection_block_push_fail_probability: Option<u8>,
     // fault injection for hiding blocks.
@@ -1921,6 +1922,7 @@ impl Default for NodeConfig {
             use_test_genesis_chainstate: None,
             always_use_affirmation_maps: true,
             require_affirmed_anchor_blocks: true,
+            assume_present_anchor_blocks: true,
             fault_injection_block_push_fail_probability: None,
             fault_injection_hide_blocks: false,
             chain_liveness_poll_time_secs: 300,
@@ -2393,6 +2395,7 @@ pub struct NodeConfigFile {
     pub use_test_genesis_chainstate: Option<bool>,
     pub always_use_affirmation_maps: Option<bool>,
     pub require_affirmed_anchor_blocks: Option<bool>,
+    pub assume_present_anchor_blocks: Option<bool>,
     /// At most, how often should the chain-liveness thread
     ///  wake up the chains-coordinator. Defaults to 300s (5 min).
     pub chain_liveness_poll_time_secs: Option<u64>,
@@ -2474,6 +2477,10 @@ impl NodeConfigFile {
             // miners should always try to mine, even if they don't have the anchored
             // blocks in the canonical affirmation map. Followers, however, can stall.
             require_affirmed_anchor_blocks: self.require_affirmed_anchor_blocks.unwrap_or(!miner),
+            // as of epoch 3.0, all prepare phases have anchor blocks.
+            // at the start of epoch 3.0, the chain stalls without anchor blocks.
+            // only set this to false if you're doing some very extreme testing.
+            assume_present_anchor_blocks: true,
             // chainstate fault_injection activation for hide_blocks.
             // you can't set this in the config file.
             fault_injection_hide_blocks: false,

testnet/stacks-node/src/run_loop/nakamoto.rs

@@ -319,6 +319,7 @@ impl RunLoop {
                 let mut fee_estimator = moved_config.make_fee_estimator();
 
                 let coord_config = ChainsCoordinatorConfig {
+                    assume_present_anchor_blocks: moved_config.node.assume_present_anchor_blocks,
                     always_use_affirmation_maps: moved_config.node.always_use_affirmation_maps,
                     require_affirmed_anchor_blocks: moved_config
                         .node

testnet/stacks-node/src/run_loop/neon.rs

@@ -625,6 +625,7 @@ impl RunLoop {
                 let mut fee_estimator = moved_config.make_fee_estimator();
 
                 let coord_config = ChainsCoordinatorConfig {
+                    assume_present_anchor_blocks: moved_config.node.assume_present_anchor_blocks,
                     always_use_affirmation_maps: moved_config.node.always_use_affirmation_maps,
                     require_affirmed_anchor_blocks: moved_config
                         .node