Solvers solution pre/post interactions

crates/driver/src/domain/competition/solution/encoding.rs

@@ -47,10 +47,10 @@ pub fn tx(
     let mut clearing_prices =
         Vec::with_capacity(solution.prices.len() + (solution.trades().len() * 2));
     let mut trades: Vec<Trade> = Vec::with_capacity(solution.trades().len());
-    let mut pre_interactions = Vec::new();
+    let mut pre_interactions = solution.pre_interactions.clone();
     let mut interactions =
         Vec::with_capacity(approvals.size_hint().0 + solution.interactions().len());
-    let mut post_interactions = Vec::new();
+    let mut post_interactions = solution.post_interactions.clone();
     let mut native_unwrap = eth::TokenAmount(eth::U256::zero());
 
     // Encode uniform clearing price vector
@@ -183,7 +183,7 @@ pub fn tx(
         interactions.push(match interaction {
             competition::solution::Interaction::Custom(interaction) => eth::Interaction {
                 value: interaction.value,
-                target: interaction.target.0.into(),
+                target: interaction.target.into(),
                 call_data: interaction.call_data.clone(),
             },
             competition::solution::Interaction::Liquidity(liquidity) => {

crates/driver/src/domain/competition/solution/mod.rs

@@ -44,7 +44,9 @@ pub struct Solution {
     id: Id,
     trades: Vec<Trade>,
     prices: Prices,
+    pre_interactions: Vec<eth::Interaction>,
     interactions: Vec<Interaction>,
+    post_interactions: Vec<eth::Interaction>,
     solver: Solver,
     weth: eth::WethAddress,
     gas: Option<eth::Gas>,
@@ -56,7 +58,9 @@ impl Solution {
         id: Id,
         trades: Vec<Trade>,
         prices: Prices,
+        pre_interactions: Vec<eth::Interaction>,
         interactions: Vec<Interaction>,
+        post_interactions: Vec<eth::Interaction>,
         solver: Solver,
         weth: eth::WethAddress,
         gas: Option<eth::Gas>,
@@ -66,7 +70,9 @@ impl Solution {
             id,
             trades,
             prices,
+            pre_interactions,
             interactions,
+            post_interactions,
             solver,
             weth,
             gas,
@@ -246,7 +252,17 @@ impl Solution {
             id: Id::Merged([self.id.ids(), other.id.ids()].concat()),
             trades: [self.trades.clone(), other.trades.clone()].concat(),
             prices,
+            pre_interactions: [
+                self.pre_interactions.clone(),
+                other.pre_interactions.clone(),
+            ]
+            .concat(),
             interactions: [self.interactions.clone(), other.interactions.clone()].concat(),
+            post_interactions: [
+                self.post_interactions.clone(),
+                other.post_interactions.clone(),
+            ]
+            .concat(),
             solver: self.solver.clone(),
             weth: self.weth,
             // Same solver are guaranteed to have the same fee handler
@@ -393,7 +409,9 @@ impl std::fmt::Debug for Solution {
             .field("id", &self.id)
             .field("trades", &self.trades)
             .field("prices", &self.prices)
+            .field("pre_interactions", &self.pre_interactions)
             .field("interactions", &self.interactions)
+            .field("post_interactions", &self.post_interactions)
             .field("solver", &self.solver.name())
             .finish()
     }

crates/driver/src/infra/solver/dto/solution.rs

@@ -2,9 +2,10 @@ use {
     crate::{
         domain::{competition, competition::order, eth, liquidity},
         infra::{solver::Config, Solver},
-        util::serialize,
+        util::{serialize, Bytes},
     },
     itertools::Itertools,
+    model::interaction::InteractionData,
     serde::Deserialize,
     serde_with::serde_as,
     std::collections::HashMap,
@@ -121,6 +122,15 @@ impl Solutions {
                         .into_iter()
                         .map(|(address, price)| (address.into(), price))
                         .collect(),
+                    solution
+                        .pre_interactions
+                        .into_iter()
+                        .map(|interaction| eth::Interaction {
+                            target: interaction.target.into(),
+                            value: interaction.value.into(),
+                            call_data: Bytes(interaction.call_data),
+                        })
+                        .collect(),
                     solution
                         .interactions
                         .into_iter()
@@ -188,6 +198,15 @@ impl Solutions {
                             }
                         })
                         .try_collect()?,
+                    solution
+                        .post_interactions
+                        .into_iter()
+                        .map(|interaction| eth::Interaction {
+                            target: interaction.target.into(),
+                            value: interaction.value.into(),
+                            call_data: Bytes(interaction.call_data),
+                        })
+                        .collect(),
                     solver.clone(),
                     weth,
                     solution.gas.map(|gas| eth::Gas(gas.into())),
@@ -221,7 +240,11 @@ pub struct Solution {
     #[serde_as(as = "HashMap<_, serialize::U256>")]
     prices: HashMap<eth::H160, eth::U256>,
     trades: Vec<Trade>,
+    #[serde(default)]
+    pre_interactions: Vec<InteractionData>,
     interactions: Vec<Interaction>,
+    #[serde(default)]
+    post_interactions: Vec<InteractionData>,
     // TODO: remove this once all solvers are updated to not return the score
     // https://github.com/cowprotocol/services/issues/2588
     #[allow(dead_code)]

crates/solvers-dto/src/solution.rs

@@ -21,7 +21,11 @@ pub struct Solution {
     #[serde_as(as = "HashMap<_, HexOrDecimalU256>")]
     pub prices: HashMap<H160, U256>,
     pub trades: Vec<Trade>,
+    #[serde(default)]
+    pub pre_interactions: Vec<InteractionData>,
     pub interactions: Vec<Interaction>,
+    #[serde(default)]
+    pub post_interactions: Vec<InteractionData>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub gas: Option<u64>,
 }
@@ -94,6 +98,14 @@ pub enum Interaction {
     Custom(CustomInteraction),
 }
 
+#[derive(Debug, Serialize)]
+#[serde(tag = "kind", rename_all = "camelCase")]
+pub struct InteractionData {
+    pub target: H160,
+    pub value: U256,
+    pub calldata: Vec<u8>,
+}
+
 #[serde_as]
 #[derive(Debug, Serialize)]
 #[serde(rename_all = "camelCase")]

crates/solvers/openapi.yml

@@ -861,12 +861,40 @@ components:
           type: array
           items:
             $ref: "#/components/schemas/Trade"
+        preInteractions:
+          description: |
+            Interactions to encode before a settlement.
+          type: array
+          items:
+            $ref: "#/components/schemas/InteractionData"
         interactions:
           description: |
             Interactions to encode within a settlement.
           type: array
+          items:
+            $ref: "#/components/schemas/InteractionData"
+        postInteractions:
+          description: |
+            Interactions to encode after a settlement.
+          type: array
           items:
             $ref: "#/components/schemas/Interaction"
         gas:
           type: integer
           description: How many units of gas this solution is estimated to cost.
+    InteractionData:
+      type: object
+      properties:
+        target:
+          $ref: "#/components/schemas/Address"
+        value:
+          $ref: "#/components/schemas/TokenAmount"
+        callData:
+          type: array
+          items:
+            $ref: "#/components/schemas/CallData"
+          description: The call data to be used for the interaction.
+    CallData:
+      description: Some `calldata` sent to a contract in a transaction encoded as a hex with `0x` prefix.
+      type: string
+      example: "0xca11da7a"

crates/solvers/src/api/routes/solve/dto/solution.rs

@@ -64,6 +64,8 @@ pub fn from_domain(solutions: &[solution::Solution]) -> super::Solutions {
                         }
                     })
                     .collect(),
+                pre_interactions: interaction_data_from_domain(&solution.pre_interactions),
+                post_interactions: interaction_data_from_domain(&solution.post_interactions),
                 interactions: solution
                     .interactions
                     .iter()
@@ -118,3 +120,16 @@ pub fn from_domain(solutions: &[solution::Solution]) -> super::Solutions {
             .collect(),
     }
 }
+
+fn interaction_data_from_domain(
+    interaction_data: &[solution::InteractionData],
+) -> Vec<InteractionData> {
+    interaction_data
+        .iter()
+        .map(|interaction| InteractionData {
+            target: interaction.target,
+            value: interaction.value.0,
+            calldata: interaction.calldata.clone(),
+        })
+        .collect()
+}

crates/solvers/src/boundary/legacy.rs

@@ -563,10 +563,12 @@ fn to_domain_solution(
                 .collect(),
         ),
         trades,
+        pre_interactions: Default::default(),
         interactions: interactions
             .into_iter()
             .map(|(interaction, _)| interaction)
             .collect(),
+        post_interactions: Default::default(),
         gas: None,
     })
 }

crates/solvers/src/boundary/naive.rs

@@ -143,6 +143,7 @@ pub fn solve(
         // auctions (which is how we model a /quote request) it can not be used for
         // quoting anyway.
         gas: None,
+        pre_interactions: vec![],
         interactions: swap
             .into_iter()
             .map(|(input, output)| {
@@ -154,6 +155,7 @@ pub fn solve(
                 })
             })
             .collect(),
+        post_interactions: vec![],
     })
 }
 

crates/solvers/src/domain/solution.rs

@@ -22,7 +22,9 @@ pub struct Solution {
     pub id: Id,
     pub prices: ClearingPrices,
     pub trades: Vec<Trade>,
+    pub pre_interactions: Vec<InteractionData>,
     pub interactions: Vec<Interaction>,
+    pub post_interactions: Vec<InteractionData>,
     pub gas: Option<eth::Gas>,
 }
 
@@ -187,7 +189,9 @@ impl Single {
                 (order.buy.token, sell.checked_sub(surplus_fee)?),
             ]),
             trades: vec![Trade::Fulfillment(Fulfillment::new(order, executed, fee)?)],
+            pre_interactions: Default::default(),
             interactions,
+            post_interactions: Default::default(),
             gas: Some(gas),
         })
     }
@@ -357,6 +361,15 @@ pub struct CustomInteraction {
     pub allowances: Vec<Allowance>,
 }
 
+/// An arbitrary ethereum interaction that is required for the settlement
+/// execution.
+#[derive(Debug)]
+pub struct InteractionData {
+    pub target: Address,
+    pub value: eth::Ether,
+    pub calldata: Vec<u8>,
+}
+
 /// Approval required to make some `[CustomInteraction]` possible.
 #[derive(Debug)]
 pub struct Allowance {

crates/solvers/src/tests/baseline/bal_liquidity.rs

@@ -117,6 +117,7 @@ async fn weighted() {
                         "executedAmount": "1000000000000000000"
                     }
                 ],
+                "preInteractions": [],
                 "interactions": [
                     {
                         "kind": "liquidity",
@@ -128,6 +129,7 @@ async fn weighted() {
                         "outputAmount": "1657855325872947866705"
                     },
                 ],
+                "postInteractions": [],
                 "gas": 206391,
             }]
         }),
@@ -258,6 +260,7 @@ async fn weighted_v3plus() {
                         "executedAmount": "1000000000000000000"
                     }
                 ],
+                "preInteractions": [],
                 "interactions": [
                     {
                         "kind": "liquidity",
@@ -269,6 +272,7 @@ async fn weighted_v3plus() {
                         "outputAmount": "1663373703594405548696"
                     },
                 ],
+                "postInteractions": [],
                 "gas": 206391,
             }]
         }),
@@ -417,6 +421,7 @@ async fn stable() {
                             "executedAmount": "10000000000000000000"
                         }
                     ],
+                    "preInteractions": [],
                     "interactions": [
                         {
                             "kind": "liquidity",
@@ -428,6 +433,7 @@ async fn stable() {
                             "outputAmount": "9999475"
                         },
                     ],
+                    "postInteractions": [],
                     "gas":  289911,
                 },
                 {
@@ -445,6 +451,7 @@ async fn stable() {
                             "executedAmount": "10000000"
                         }
                     ],
+                    "preInteractions": [],
                     "interactions": [
                         {
                             "kind": "liquidity",
@@ -456,6 +463,7 @@ async fn stable() {
                             "outputAmount": "10000000"
                         },
                     ],
+                    "postInteractions": [],
                     "gas":  289911,
                 },
             ]
@@ -588,6 +596,7 @@ async fn composable_stable_v4() {
                             "executedAmount": "10000000000000000000"
                         }
                     ],
+                    "preInteractions": [],
                     "interactions": [
                         {
                             "kind": "liquidity",
@@ -599,6 +608,7 @@ async fn composable_stable_v4() {
                             "outputAmount": "10029862202766050434"
                         },
                     ],
+                    "postInteractions": [],
                     "gas": 289911,
                 },
             ]