feat(minibf): governance dreps endpoint

CHANGELOG.md

@@ -2,6 +2,12 @@
 
 All notable changes to this project will be documented in this file.
 
+## [Unreleased]
+
+### 🚀 Features
+
+- *(minibf)* Add `/governance/dreps` endpoint
+
 ## [1.5.0] - 2026-07-16
 
 ### 🚀 Features

crates/cardano/src/model/dreps.rs

@@ -48,6 +48,11 @@ pub struct DRepState {
     // `None`. Index 7 must not be reused for anything else.
     #[n(7)]
     pub anchor: Option<Anchor>,
+
+    /// First on-chain reference by any certificate, vote delegations included.
+    /// Mirrors db-sync's `drep_hash` insertion order.
+    #[n(8)]
+    pub first_seen_at: Option<(BlockSlot, TxOrder)>,
 }
 
 impl DRepState {
@@ -61,6 +66,7 @@ impl DRepState {
             deposit: 0,
             identifier,
             anchor: None,
+            first_seen_at: None,
         }
     }
 
@@ -98,6 +104,7 @@ pub(crate) mod testing {
             expired in any::<bool>(),
             deposit in root::any_lovelace(),
             anchor in prop::option::of(root::any_anchor()),
+            first_seen_at in prop::option::of((root::any_slot(), root::any_tx_order())),
         ) -> DRepState {
             DRepState {
                 identifier,
@@ -108,6 +115,7 @@ pub(crate) mod testing {
                 expired,
                 deposit,
                 anchor,
+                first_seen_at,
             }
         }
     }
@@ -128,6 +136,7 @@ pub struct DRepRegistration {
     pub(crate) prev_registered_at: Option<(BlockSlot, TxOrder)>,
     pub(crate) prev_voting_power: u64,
     pub(crate) prev_deposit: u64,
+    pub(crate) prev_anchor: Option<Anchor>,
 }
 
 impl DRepRegistration {
@@ -148,6 +157,7 @@ impl DRepRegistration {
             prev_registered_at: None,
             prev_voting_power: 0,
             prev_deposit: 0,
+            prev_anchor: None,
         }
     }
 }
@@ -168,11 +178,15 @@ impl dolos_core::EntityDelta for DRepRegistration {
         self.prev_registered_at = entity.registered_at;
         self.prev_voting_power = entity.voting_power;
         self.prev_deposit = entity.deposit;
+        self.prev_anchor = entity.anchor.clone();
 
         // apply changes
         entity.registered_at = Some((self.slot, self.txorder));
         entity.voting_power = self.deposit;
         entity.deposit = self.deposit;
+
+        // Registration anchor replaces the previous one (including clearing it).
+        entity.anchor = self.anchor.clone();
     }
 
     fn undo(&self, entity: &mut Option<DRepState>) {
@@ -184,6 +198,7 @@ impl dolos_core::EntityDelta for DRepRegistration {
         entity.registered_at = self.prev_registered_at;
         entity.voting_power = self.prev_voting_power;
         entity.deposit = self.prev_deposit;
+        entity.anchor = self.prev_anchor.clone();
     }
 }
 
@@ -243,6 +258,61 @@ impl dolos_core::EntityDelta for DRepUnRegistration {
     }
 }
 
+/// Records the first on-chain appearance of a DRep, creating the entity if it
+/// doesn't exist yet.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct DRepSeen {
+    pub(crate) drep: DRep,
+    pub(crate) slot: BlockSlot,
+    pub(crate) txorder: TxOrder,
+
+    // undo
+    pub(crate) prev_first_seen_at: Option<(BlockSlot, TxOrder)>,
+    pub(crate) was_new: bool,
+}
+
+impl DRepSeen {
+    pub fn new(drep: DRep, slot: BlockSlot, txorder: TxOrder) -> Self {
+        Self {
+            drep,
+            slot,
+            txorder,
+            prev_first_seen_at: None,
+            was_new: false,
+        }
+    }
+}
+
+impl dolos_core::EntityDelta for DRepSeen {
+    type Entity = DRepState;
+
+    fn key(&self) -> NsKey {
+        NsKey::from((DRepState::NS, drep_to_entity_key(&self.drep)))
+    }
+
+    fn apply(&mut self, entity: &mut Option<DRepState>) {
+        self.was_new = entity.is_none();
+
+        let entity = entity.get_or_insert_with(|| DRepState::new(self.drep.clone()));
+
+        // save undo info
+        self.prev_first_seen_at = entity.first_seen_at;
+
+        // only the earliest sighting counts
+        if entity.first_seen_at.is_none() {
+            entity.first_seen_at = Some((self.slot, self.txorder));
+        }
+    }
+
+    fn undo(&self, entity: &mut Option<DRepState>) {
+        if self.was_new {
+            *entity = None;
+        } else if let Some(state) = entity {
+            state.first_seen_at = self.prev_first_seen_at;
+        }
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct DRepActivity {
     pub(crate) drep: DRep,
@@ -439,6 +509,16 @@ mod prop_tests {
         }
     }
 
+    prop_compose! {
+        fn any_drep_seen()(
+            drep in root::any_drep(),
+            slot in root::any_slot(),
+            txorder in root::any_tx_order(),
+        ) -> DRepSeen {
+            DRepSeen::new(drep, slot, txorder)
+        }
+    }
+
     proptest! {
         #[test]
         fn drep_registration_roundtrip(
@@ -487,5 +567,28 @@ mod prop_tests {
         ) {
             assert_delta_roundtrip(Some(entity), delta);
         }
+
+        #[test]
+        fn drep_seen_roundtrip(
+            entity in prop::option::of(any_drep_state()),
+            delta in any_drep_seen(),
+        ) {
+            assert_delta_roundtrip(entity, delta);
+        }
+    }
+
+    #[test]
+    fn drep_seen_keeps_earliest_sighting() {
+        use dolos_core::EntityDelta as _;
+
+        let drep = DRep::Key([1u8; 28].into());
+        let mut entity = None;
+
+        DRepSeen::new(drep.clone(), 100, 3).apply(&mut entity);
+        assert_eq!(entity.as_ref().unwrap().first_seen_at, Some((100, 3)));
+
+        // a later sighting must not move the first appearance
+        DRepSeen::new(drep, 200, 1).apply(&mut entity);
+        assert_eq!(entity.unwrap().first_seen_at, Some((100, 3)));
     }
 }

crates/cardano/src/model/mod.rs

@@ -233,6 +233,7 @@ pub enum CardanoDelta {
     DRepAnchorUpdate(Box<DRepAnchorUpdate>),
     NewProposalV2(Box<NewProposalV2>),
     VoteCast(Box<VoteCast>),
+    DRepSeen(Box<DRepSeen>),
 }
 
 impl CardanoDelta {
@@ -284,6 +285,7 @@ delta_from!(DRepRegistration);
 delta_from!(DRepUnRegistration);
 delta_from!(DRepActivity);
 delta_from!(DRepExpiration);
+delta_from!(DRepSeen);
 delta_from!(WithdrawalInc);
 delta_from!(VoteDelegation);
 delta_from!(PParamsUpdate);
@@ -344,6 +346,7 @@ impl dolos_core::EntityDelta for CardanoDelta {
             Self::DRepUnRegistration(x) => x.key(),
             Self::DRepExpiration(x) => x.key(),
             Self::DRepAnchorUpdate(x) => x.key(),
+            Self::DRepSeen(x) => x.key(),
             Self::WithdrawalInc(x) => x.key(),
             Self::VoteDelegation(x) => x.key(),
             Self::PParamsUpdate(x) => x.key(),
@@ -397,6 +400,7 @@ impl dolos_core::EntityDelta for CardanoDelta {
             Self::DRepActivity(x) => Self::downcast_apply(x.as_mut(), entity),
             Self::DRepExpiration(x) => Self::downcast_apply(x.as_mut(), entity),
             Self::DRepAnchorUpdate(x) => Self::downcast_apply(x.as_mut(), entity),
+            Self::DRepSeen(x) => Self::downcast_apply(x.as_mut(), entity),
             Self::WithdrawalInc(x) => Self::downcast_apply(x.as_mut(), entity),
             Self::VoteDelegation(x) => Self::downcast_apply(x.as_mut(), entity),
             Self::PParamsUpdate(x) => Self::downcast_apply(x.as_mut(), entity),
@@ -450,6 +454,7 @@ impl dolos_core::EntityDelta for CardanoDelta {
             Self::DRepActivity(x) => Self::downcast_undo(x.as_ref(), entity),
             Self::DRepExpiration(x) => Self::downcast_undo(x.as_ref(), entity),
             Self::DRepAnchorUpdate(x) => Self::downcast_undo(x.as_ref(), entity),
+            Self::DRepSeen(x) => Self::downcast_undo(x.as_ref(), entity),
             Self::WithdrawalInc(x) => Self::downcast_undo(x.as_ref(), entity),
             Self::VoteDelegation(x) => Self::downcast_undo(x.as_ref(), entity),
             Self::PParamsUpdate(x) => Self::downcast_undo(x.as_ref(), entity),

crates/cardano/src/roll/dreps.rs

@@ -8,8 +8,9 @@ use pallas::ledger::{
 
 use super::WorkDeltas;
 use crate::{
-    owned::OwnedMultiEraOutput, pallas_extras::stake_cred_to_drep, roll::BlockVisitor,
-    DRepActivity, DRepAnchorUpdate, DRepRegistration, DRepUnRegistration,
+    owned::OwnedMultiEraOutput, pallas_extras, pallas_extras::stake_cred_to_drep,
+    roll::BlockVisitor, DRepActivity, DRepAnchorUpdate, DRepRegistration, DRepSeen,
+    DRepUnRegistration,
 };
 
 fn cert_drep(cert: &MultiEraCert) -> Option<DRep> {
@@ -64,10 +65,16 @@ impl BlockVisitor for DRepStateVisitor {
         order: &TxOrder,
         cert: &MultiEraCert,
     ) -> Result<(), ChainError> {
+        if let Some(cert) = pallas_extras::cert_as_vote_delegation(cert) {
+            deltas.add_for_entity(DRepSeen::new(cert.drep, block.slot(), *order));
+        }
+
         let Some(drep) = cert_drep(cert) else {
             return Ok(());
         };
 
+        deltas.add_for_entity(DRepSeen::new(drep.clone(), block.slot(), *order));
+
         if let MultiEraCert::Conway(conway) = &cert {
             match conway.deref().deref() {
                 conway::Certificate::RegDRepCert(_, deposit, anchor) => {

crates/minibf/src/lib.rs

@@ -487,6 +487,7 @@ where
         .route("/pools/extended", get(routes::pools::all_extended::<D>))
         .route("/pools/retiring", get(routes::pools::all_retiring::<D>))
         .route("/pools/{id}", get(routes::pools::by_id::<D>))
+        .route("/governance/dreps", get(routes::governance::all_dreps::<D>))
         .route(
             "/governance/dreps/{drep_id}",
             get(routes::governance::drep_by_id::<D>),

crates/minibf/src/mapping.rs

@@ -79,7 +79,7 @@ pub fn rational_to_f64<const DECIMALS: u8>(val: &alonzo::RationalNumber) -> f64
     round_f64::<DECIMALS>(res)
 }
 
-const DREP_HRP: bech32::Hrp = bech32::Hrp::parse_unchecked("drep");
+pub const DREP_HRP: bech32::Hrp = bech32::Hrp::parse_unchecked("drep");
 const POOL_HRP: bech32::Hrp = bech32::Hrp::parse_unchecked("pool");
 const ASSET_HRP: bech32::Hrp = bech32::Hrp::parse_unchecked("asset");
 const CALIDUS_HRP: bech32::Hrp = bech32::Hrp::parse_unchecked("calidus");