feat(network): implement get stake pool parameters query (#554)

pallas-network/src/miniprotocols/localstate/queries_v16/codec.rs

@@ -339,6 +339,29 @@ impl<C> minicbor::encode::Encode<C> for RationalNumber {
     }
 }
 
+impl<'b, C> minicbor::decode::Decode<'b, C> for PoolIds {
+    fn decode(d: &mut minicbor::Decoder<'b>, ctx: &mut C) -> Result<Self, minicbor::decode::Error> {
+        d.tag()?;
+
+        Ok(PoolIds {
+            hashes: d.decode_with(ctx)?,
+        })
+    }
+}
+
+impl<C> minicbor::encode::Encode<C> for PoolIds {
+    fn encode<W: minicbor::encode::Write>(
+        &self,
+        e: &mut minicbor::Encoder<W>,
+        ctx: &mut C,
+    ) -> Result<(), minicbor::encode::Error<W::Error>> {
+        e.tag(Tag::new(258))?;
+        e.encode_with(self.hashes.clone(), ctx)?;
+
+        Ok(())
+    }
+}
+
 impl<'b, C> minicbor::decode::Decode<'b, C> for TransactionOutput {
     fn decode(d: &mut minicbor::Decoder<'b>, ctx: &mut C) -> Result<Self, minicbor::decode::Error> {
         match d.datatype()? {

pallas-network/src/miniprotocols/localstate/queries_v16/mod.rs

@@ -1,17 +1,21 @@
 // TODO: this should move to pallas::ledger crate at some point
 
 use pallas_crypto::hash::Hash;
-use std::collections::BTreeSet;
+use std::collections::{BTreeMap, BTreeSet};
 use std::hash::Hash as StdHash;
 // required for derive attrs to work
 use pallas_codec::minicbor::{self};
 
-use pallas_codec::utils::{AnyUInt, Bytes, KeyValuePairs, TagWrap};
+use pallas_codec::utils::{AnyUInt, Bytes, KeyValuePairs, Nullable, TagWrap};
 use pallas_codec::{
     minicbor::{Decode, Encode},
     utils::AnyCbor,
 };
 
+pub mod primitives;
+
+pub use primitives::{PoolMetadata, Relay};
+
 use crate::miniprotocols::Point;
 
 use super::{Client, ClientError};
@@ -39,7 +43,7 @@ pub enum BlockQuery {
     GetRewardProvenance,
     GetUTxOByTxIn(TxIns),
     GetStakePools,
-    GetStakePoolParams(AnyCbor),
+    GetStakePoolParams(PoolIds),
     GetRewardInfoPools,
     GetPoolState(AnyCbor),
     GetStakeSnapshots(Pools),
@@ -197,6 +201,19 @@ pub struct StakeDistribution {
     pub pools: KeyValuePairs<Bytes, Pool>,
 }
 
+/// The use of `BTreeMap`s as per [Pools] definition ensures that the hashes are
+/// in order (otherwise, the node will reject some queries).
+#[derive(Debug, PartialEq, Clone)]
+pub struct PoolIds {
+    pub hashes: Pools,
+}
+
+impl From<Pools> for PoolIds {
+    fn from(hashes: Pools) -> Self {
+        Self { hashes }
+    }
+}
+
 #[derive(Debug, Encode, Decode, PartialEq, Clone)]
 pub struct Pool {
     #[n(0)]
@@ -206,6 +223,39 @@ pub struct Pool {
     pub hashes: Bytes,
 }
 
+// Essentially the `PoolRegistration` component of `Certificate` at
+// `pallas-primitives/src/alonzo/model.rs`, with types modified for the present
+// context
+#[derive(Debug, Encode, Decode, PartialEq, Clone)]
+pub struct PoolParams {
+    #[n(0)]
+    pub operator: Bytes,
+
+    #[n(1)]
+    pub vrf_keyhash: Bytes,
+
+    #[n(2)]
+    pub pledge: Coin,
+
+    #[n(3)]
+    pub cost: Coin,
+
+    #[n(4)]
+    pub margin: UnitInterval,
+
+    #[n(5)]
+    pub reward_account: Addr,
+
+    #[n(6)]
+    pub pool_owners: PoolIds,
+
+    #[n(7)]
+    pub relays: Vec<Relay>,
+
+    #[n(8)]
+    pub pool_metadata: Nullable<PoolMetadata>,
+}
+
 /// Type used at [GenesisConfig], which is a fraction that is CBOR-encoded
 /// as an untagged array.
 #[derive(Debug, Encode, Decode, PartialEq, Clone)]
@@ -504,6 +554,20 @@ pub async fn get_cbor(
     Ok(result)
 }
 
+/// Get parameters for the given pools.
+pub async fn get_stake_pool_params(
+    client: &mut Client,
+    era: u16,
+    pool_ids: PoolIds,
+) -> Result<BTreeMap<Bytes, PoolParams>, ClientError> {
+    let query = BlockQuery::GetStakePoolParams(pool_ids);
+    let query = LedgerQuery::BlockQuery(era, query);
+    let query = Request::LedgerQuery(query);
+    let result: (_,) = client.query(query).await?;
+
+    Ok(result.0)
+}
+
 /// Get the genesis configuration for the given era.
 pub async fn get_genesis_config(
     client: &mut Client,

pallas-network/src/miniprotocols/localstate/queries_v16/primitives.rs

@@ -0,0 +1,91 @@
+// Material brought from `pallas-primitives`
+// TODO: Refactor in order to avoid repetition.
+pub use pallas_codec::utils::{Bytes, Nullable};
+pub use pallas_crypto::hash::Hash;
+
+use pallas_codec::minicbor::{self, Decode, Encode};
+
+#[derive(Encode, Decode, Debug, PartialEq, Eq, Clone)]
+pub struct PoolMetadata {
+    #[n(0)]
+    pub url: String,
+
+    #[n(1)]
+    pub hash: PoolMetadataHash,
+}
+
+pub type PoolMetadataHash = Hash<32>;
+
+pub type Port = u32;
+
+pub type IPv4 = Bytes;
+
+pub type IPv6 = Bytes;
+
+pub type DnsName = String;
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub enum Relay {
+    SingleHostAddr(Nullable<Port>, Nullable<IPv4>, Nullable<IPv6>),
+    SingleHostName(Nullable<Port>, DnsName),
+    MultiHostName(DnsName),
+}
+
+// Move to `codec.rs`?
+impl<'b, C> minicbor::decode::Decode<'b, C> for Relay {
+    fn decode(d: &mut minicbor::Decoder<'b>, ctx: &mut C) -> Result<Self, minicbor::decode::Error> {
+        d.array()?;
+        let variant = d.u16()?;
+
+        match variant {
+            0 => Ok(Relay::SingleHostAddr(
+                d.decode_with(ctx)?,
+                d.decode_with(ctx)?,
+                d.decode_with(ctx)?,
+            )),
+            1 => Ok(Relay::SingleHostName(
+                d.decode_with(ctx)?,
+                d.decode_with(ctx)?,
+            )),
+            2 => Ok(Relay::MultiHostName(d.decode_with(ctx)?)),
+            _ => Err(minicbor::decode::Error::message(
+                "invalid variant id for Relay",
+            )),
+        }
+    }
+}
+
+impl<C> minicbor::encode::Encode<C> for Relay {
+    fn encode<W: minicbor::encode::Write>(
+        &self,
+        e: &mut minicbor::Encoder<W>,
+        ctx: &mut C,
+    ) -> Result<(), minicbor::encode::Error<W::Error>> {
+        match self {
+            Relay::SingleHostAddr(a, b, c) => {
+                e.array(4)?;
+                e.encode_with(0, ctx)?;
+                e.encode_with(a, ctx)?;
+                e.encode_with(b, ctx)?;
+                e.encode_with(c, ctx)?;
+
+                Ok(())
+            }
+            Relay::SingleHostName(a, b) => {
+                e.array(3)?;
+                e.encode_with(1, ctx)?;
+                e.encode_with(a, ctx)?;
+                e.encode_with(b, ctx)?;
+
+                Ok(())
+            }
+            Relay::MultiHostName(a) => {
+                e.array(2)?;
+                e.encode_with(2, ctx)?;
+                e.encode_with(a, ctx)?;
+
+                Ok(())
+            }
+        }
+    }
+}