Fix OKX integration approve transaction

Cargo.toml

@@ -44,6 +44,7 @@ tower = "0.4"
 tower-http = { version = "0.4", features = ["trace"] }
 tracing = "0.1"
 web3 = "0.19"
+lru = "0.12.5"
 
 contracts = { git = "https://github.com/cowprotocol/services.git", tag = "v2.294.0", package = "contracts" }
 ethrpc = { git = "https://github.com/cowprotocol/services.git", tag = "v2.294.0", package = "ethrpc" }

config/example.okx.toml

@@ -6,7 +6,7 @@ node-url = "http://localhost:8545"
 chain-id = "1"
 
 # Optionally specify a custom OKX Swap API endpoint
-# endpoint = "https://www.okx.com/api/v5/dex/aggregator/swap"
+# endpoint = "https://www.okx.com/api/v5/dex/aggregator/"
 
 # OKX Project ID. Instruction on how to create a project:
 # https://www.okx.com/en-au/web3/build/docs/waas/introduction-to-developer-portal-interface#create-project

src/infra/config/dex/okx/file.rs

@@ -60,7 +60,7 @@ impl Into<okx::OkxCredentialsConfig> for OkxCredentialsConfig {
 }
 
 fn default_endpoint() -> reqwest::Url {
-    "https://www.okx.com/api/v5/dex/aggregator/swap"
+    "https://www.okx.com/api/v5/dex/aggregator/"
         .parse()
         .unwrap()
 }

src/infra/dex/okx/dto.rs

@@ -64,31 +64,14 @@ impl SwapRequest {
     }
 }
 
-/// A OKX API swap response - generic wrapper for success and failure cases.
+/// A OKX API swap response.
 ///
 /// See [API](https://www.okx.com/en-au/web3/build/docs/waas/dex-swap)
 /// documentation for more detailed information on each parameter.
 #[serde_as]
-#[derive(Deserialize)]
+#[derive(Deserialize, Clone)]
 #[serde(rename_all = "camelCase")]
 pub struct SwapResponse {
-    /// Error code, 0 for success, otherwise one of:
-    /// [error codes](https://www.okx.com/en-au/web3/build/docs/waas/dex-error-code)
-    #[serde_as(as = "serde_with::DisplayFromStr")]
-    pub code: i64,
-
-    /// Response data.
-    pub data: Vec<SwapResponseInner>,
-
-    /// Error code text message.
-    pub msg: String,
-}
-
-/// A OKX API swap response.
-#[serde_as]
-#[derive(Deserialize)]
-#[serde(rename_all = "camelCase")]
-pub struct SwapResponseInner {
     /// Quote execution path.
     pub router_result: SwapResponseRouterResult,
 
@@ -101,7 +84,7 @@ pub struct SwapResponseInner {
 /// For all possible fields look into the documentation:
 /// [API](https://www.okx.com/en-au/web3/build/docs/waas/dex-swap)
 #[serde_as]
-#[derive(Deserialize)]
+#[derive(Deserialize, Clone)]
 #[serde(rename_all = "camelCase")]
 pub struct SwapResponseRouterResult {
     /// The information of a token to be sold.
@@ -124,7 +107,7 @@ pub struct SwapResponseRouterResult {
 /// For all possible fields look into the documentation:
 /// [API](https://www.okx.com/en-au/web3/build/docs/waas/dex-swap)
 #[serde_as]
-#[derive(Deserialize)]
+#[derive(Deserialize, Clone)]
 #[serde(rename_all = "camelCase")]
 pub struct SwapResponseFromToToken {
     /// Address of the token smart contract.
@@ -136,7 +119,7 @@ pub struct SwapResponseFromToToken {
 /// For all possible fields look into the documentation:
 /// [API](https://www.okx.com/en-au/web3/build/docs/waas/dex-swap)
 #[serde_as]
-#[derive(Deserialize)]
+#[derive(Deserialize, Clone)]
 #[serde(rename_all = "camelCase")]
 pub struct SwapResponseTx {
     /// Estimated amount of the gas limit.
@@ -151,6 +134,66 @@ pub struct SwapResponseTx {
     pub data: Vec<u8>,
 }
 
+/// A OKX API approve transaction request.
+///
+/// See [API](https://www.okx.com/en-au/web3/build/docs/waas/dex-approve-transaction)
+/// documentation for more detailed information on each parameter.
+#[serde_as]
+#[derive(Clone, Default, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ApproveTransactionRequest {
+    /// Chain ID
+    #[serde_as(as = "serde_with::DisplayFromStr")]
+    pub chain_id: u64,
+
+    /// Contract address of a token to be permitted.
+    pub token_contract_address: H160,
+
+    /// The amount of token that needs to be permitted (in minimal divisible
+    /// units).
+    #[serde_as(as = "serialize::U256")]
+    pub approve_amount: U256,
+}
+
+impl ApproveTransactionRequest {
+    pub fn with_domain(chain_id: u64, order: &dex::Order) -> Self {
+        Self {
+            chain_id,
+            token_contract_address: order.sell.0,
+            approve_amount: order.amount.get(),
+        }
+    }
+}
+
+/// A OKX API approve transaction response.
+/// Deserializing fields which are only used by the implementation.
+/// See [API](https://www.okx.com/en-au/web3/build/docs/waas/dex-approve-transaction)
+/// documentation for more detailed information on each parameter.
+#[serde_as]
+#[derive(Clone, Default, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ApproveTransactionResponse {
+    /// The contract address of OKX DEX approve.
+    pub dex_contract_address: H160,
+}
+
+/// A OKX API response - generic wrapper for success and failure cases.
+#[serde_as]
+#[derive(Deserialize, Clone)]
+#[serde(rename_all = "camelCase")]
+pub struct Response<T> {
+    /// Error code, 0 for success, otherwise one of:
+    /// [error codes](https://www.okx.com/en-au/web3/build/docs/waas/dex-error-code)
+    #[serde_as(as = "serde_with::DisplayFromStr")]
+    pub code: i64,
+
+    /// Response data.
+    pub data: Vec<T>,
+
+    /// Error code text message.
+    pub msg: String,
+}
+
 #[derive(Deserialize)]
 pub struct Error {
     pub code: i64,