Add getLatestBlockhash API method as replacement for getRecentBlockhash

Sources/SolanaSwift/APIClient/APIClient+Extension.swift

@@ -9,8 +9,9 @@ public extension SolanaAPIClient {
         try await getMinimumBalanceForRentExemption(dataLength: span, commitment: "recent")
     }
 
+    @available(*, deprecated, message: "Use getLatestBlockhash instead")
     func getRecentBlockhash() async throws -> String {
-        try await getRecentBlockhash(commitment: nil)
+        try await getLatestBlockhash(commitment: nil, minContextSlot: nil).blockhash
     }
 
     func observeSignatureStatus(signature: String) -> AsyncStream<PendingTransactionStatus> {

Sources/SolanaSwift/APIClient/Networking/JSONRPCAPIClient.swift

@@ -104,13 +104,21 @@ public class JSONRPCAPIClient: SolanaAPIClient {
         )
     }
 
+    @available(*, deprecated, message: "Use getLatestBlockhash instead")
     public func getRecentBlockhash(commitment: Commitment? = nil) async throws -> String {
-        let result: Rpc<Fee> = try await get(method: "getRecentBlockhash",
-                                             params: [RequestConfiguration(commitment: commitment)])
-        guard let blockhash = result.value.blockhash else {
-            throw APIClientError.blockhashNotFound
-        }
-        return blockhash
+        try await getLatestBlockhash(commitment: commitment, minContextSlot: nil).blockhash
+    }
+
+    public func getLatestBlockhash(commitment: Commitment?, minContextSlot: UInt64?) async throws -> LatestBlockhashResponse {
+        let config = RequestConfiguration(
+            commitment: commitment,
+            minContextSlot: minContextSlot
+        )
+        let result: Rpc<LatestBlockhashResponse> = try await get(
+            method: "getLatestBlockhash",
+            params: [config]
+        )
+        return result.value
     }
 
     public func getSignatureStatuses(signatures: [String],

Sources/SolanaSwift/APIClient/SolanaAPIClient.swift

@@ -276,13 +276,15 @@ public protocol SolanaAPIClient {
     ///
     func observeSignatureStatus(signature: String, timeout: Int, delay: Int) -> AsyncStream<PendingTransactionStatus>
 
-    /// Returns a recent block hash from the ledger, and a fee schedule that can be used to compute the cost of
-    /// submitting a transaction using it.
+    /// Returns the latest blockhash and last valid block height
     /// - Parameters:
-    ///  - commitment: (optional) Commitment
-    /// - Throws: APIClientError
-    /// - SeeAlso https://docs.solana.com/developing/clients/jsonrpc-api#getrecentblockhash
-    ///
+    ///   - commitment: Optional commitment level
+    ///   - minContextSlot: The minimum slot that the request can be evaluated at
+    /// - Returns: Latest blockhash response containing the blockhash and lastValidBlockHeight
+    /// - SeeAlso: https://solana.com/docs/rpc/http/getlatestblockhash
+    func getLatestBlockhash(commitment: Commitment?, minContextSlot: UInt64?) async throws -> LatestBlockhashResponse
+
+    @available(*, deprecated, message: "Use getLatestBlockhash instead")
     func getRecentBlockhash(commitment: Commitment?) async throws -> String
 
     /// Returns signatures for confirmed transactions that include the given address in their accountKeys list.

Sources/SolanaSwift/Models/Models.swift

@@ -140,6 +140,11 @@ public struct LargestAccount: Decodable {
     public let address: String
 }
 
+public struct LatestBlockhashResponse: Decodable {
+    public let blockhash: String
+    public let lastValidBlockHeight: UInt64
+}
+
 public struct ProgramAccounts<T: BufferLayout>: Decodable {
     public let accounts: [ProgramAccount<T>]
     public init(from decoder: Decoder) throws {

Sources/SolanaSwift/Models/RequestModels.swift

@@ -81,6 +81,7 @@ public struct RequestConfiguration: Encodable {
     public let skipPreflight: Bool?
     public let preflightCommitment: Commitment?
     public let searchTransactionHistory: Bool?
+    public let minContextSlot: UInt64?
     public let replaceRecentBlockhash: Bool?
 
     public init?(
@@ -94,6 +95,7 @@ public struct RequestConfiguration: Encodable {
         skipPreflight: Bool? = nil,
         preflightCommitment: Commitment? = nil,
         searchTransactionHistory: Bool? = nil,
+        minContextSlot: UInt64? = nil,
         replaceRecentBlockhash: Bool? = nil
     ) {
         if commitment == nil,
@@ -106,8 +108,8 @@ public struct RequestConfiguration: Encodable {
            skipPreflight == nil,
            preflightCommitment == nil,
            searchTransactionHistory == nil,
-           replaceRecentBlockhash == nil
-        {
+           minContextSlot == nil,
+           replaceRecentBlockhash == nil {
             return nil
         }
 
@@ -121,6 +123,7 @@ public struct RequestConfiguration: Encodable {
         self.skipPreflight = skipPreflight
         self.preflightCommitment = preflightCommitment
         self.searchTransactionHistory = searchTransactionHistory
+        self.minContextSlot = minContextSlot
         self.replaceRecentBlockhash = replaceRecentBlockhash
     }
 }