External solver support in e2e tests (#2515)

# Description
A new function `start_protocol_external_solver` is created which allows
e2e tests to easily setup the protocol with an external solver that uses
the new solver API.

# Changes
- Add a `start_protocol_external_solver` function 
- Add a `run_baseline` flag to the `start_protocol` functions that use
external solvers, which if set to true will also run a baseline solver
alongside the external solver.

## How to test
- CI will run, but as I'm not a contributor, forked tests can't run
until merge. I've run them locally and they pass.
 - Enso CI tests run and pass against this commit hash.

---------

Co-authored-by: Haris Angelidakis <64154020+harisang@users.noreply.github.com>
Co-authored-by: Martin Beckmann <martin.beckmann@protonmail.com>

crates/e2e/src/setup/services.rs

@@ -1,5 +1,5 @@
 use {
-    super::{colocation::start_legacy_solver, TestAccount},
+    super::TestAccount,
     crate::setup::{
         colocation::{self, SolverEngine},
         wait_for_condition,
@@ -9,7 +9,7 @@ use {
     app_data::{AppDataDocument, AppDataHash},
     autopilot::infra::persistence::dto,
     clap::Parser,
-    ethcontract::{H256, U256},
+    ethcontract::H256,
     model::{
         order::{Order, OrderCreation, OrderUid},
         quote::{OrderQuoteRequest, OrderQuoteResponse},
@@ -209,52 +209,61 @@ impl<'a> Services<'a> {
         .await;
     }
 
-    /// Starts a basic version of the protocol with a single legacy solver and
-    /// quoter.
-    pub async fn start_protocol_legacy_solver(
+    /// Starts a basic version of the protocol with a single external solver.
+    /// Optionally starts a baseline solver and uses it for price estimation.
+    pub async fn start_protocol_external_solver(
         &self,
         solver: TestAccount,
         solver_endpoint: Option<Url>,
-        quoter_endpoint: Option<Url>,
-        chain_id: Option<U256>,
+        run_baseline: bool,
     ) {
         let external_solver_endpoint =
-            solver_endpoint.unwrap_or("http://localhost:8000/solve".parse().unwrap());
-        let colocated_solver_endpoint =
-            start_legacy_solver(external_solver_endpoint, chain_id).await;
+            solver_endpoint.unwrap_or("http://localhost:8000/".parse().unwrap());
 
-        let external_quoter_endpoint =
-            quoter_endpoint.unwrap_or("http://localhost:8000/quote".parse().unwrap());
-        let colocated_quoter_endpoint =
-            start_legacy_solver(external_quoter_endpoint, chain_id).await;
+        let mut solvers = vec![SolverEngine {
+            name: "test_solver".into(),
+            account: solver.clone(),
+            endpoint: external_solver_endpoint,
+        }];
 
-        colocation::start_driver(
-            self.contracts,
-            vec![
-                SolverEngine {
-                    name: "test_solver".into(),
-                    account: solver.clone(),
-                    endpoint: colocated_solver_endpoint,
-                },
-                SolverEngine {
-                    name: "test_quoter".into(),
-                    account: solver,
-                    endpoint: colocated_quoter_endpoint,
-                },
-            ],
-        );
-        self.start_autopilot(
-            Some(Duration::from_secs(11)),
-            vec![
+        let (autopilot_args, api_args) = if run_baseline {
+            let baseline_solver_endpoint =
+                colocation::start_baseline_solver(self.contracts.weth.address()).await;
+
+            solvers.push(SolverEngine {
+                name: "baseline_solver".into(),
+                account: solver,
+                endpoint: baseline_solver_endpoint,
+            });
+
+            // Here we call the baseline_solver "test_quoter" to make the native price
+            // estimation use the baseline_solver instead of the test_quoter
+            let autopilot_args = vec![
+                "--drivers=test_solver|http://localhost:11088/test_solver".to_string(),
+                "--price-estimation-drivers=test_quoter|http://localhost:11088/baseline_solver,test_solver|http://localhost:11088/test_solver".to_string(),
+            ];
+            let api_args = vec![
+                "--price-estimation-drivers=test_quoter|http://localhost:11088/baseline_solver,test_solver|http://localhost:11088/test_solver".to_string(),
+            ];
+            (autopilot_args, api_args)
+        } else {
+            let autopilot_args = vec![
                 "--drivers=test_solver|http://localhost:11088/test_solver".to_string(),
-                "--price-estimation-drivers=test_quoter|http://localhost:11088/test_quoter"
+                "--price-estimation-drivers=test_quoter|http://localhost:11088/test_solver"
                     .to_string(),
-            ],
-        );
-        self.start_api(vec![
-            "--price-estimation-drivers=test_quoter|http://localhost:11088/test_quoter".to_string(),
-        ])
-        .await;
+            ];
+
+            let api_args = vec![
+                "--price-estimation-drivers=test_quoter|http://localhost:11088/test_solver"
+                    .to_string(),
+            ];
+            (autopilot_args, api_args)
+        };
+
+        colocation::start_driver(self.contracts, solvers);
+
+        self.start_autopilot(Some(Duration::from_secs(11)), autopilot_args);
+        self.start_api(api_args).await;
     }
 
     async fn wait_for_api_to_come_up() {