Fix encoding of dates in URL queries

Sources/SotoCore/Encoder/CodableProperties/DateCoders.swift

@@ -126,4 +126,8 @@ public struct UnixEpochDateCoder: CustomDecoder, CustomEncoder {
         var container = encoder.singleValueContainer()
         try container.encode(value.timeIntervalSince1970)
     }
+
+    public static func string(from value: Date) -> String? {
+        Int(value.timeIntervalSince1970).description
+    }
 }

Sources/SotoCore/Encoder/RequestContainer.swift

@@ -63,7 +63,7 @@ public class RequestEncodingContainer {
         if queryParams.count > 0 {
             let urlQueryString =
                 queryParams
-                .map { (key: $0.key, value: "\($0.value)") }
+                .map { (key: $0.key, value: $0.value) }
                 .sorted {
                     // sort by key. if key are equal then sort by value
                     if $0.key < $1.key { return true }
@@ -113,12 +113,20 @@ public class RequestEncodingContainer {
         }
     }
 
-    /// Write dictionary key value pairs to headers with prefix added to the keys
+    /// Write date to headers
     @inlinable
     public func encodeHeader(_ value: Date, key: String) {
         self.encodeHeader(HTTPHeaderDateCoder.string(from: value), key: key)
     }
 
+    /// Write date to headers
+    @inlinable
+    public func encodeHeader(_ value: Date?, key: String) {
+        if let value {
+            self.encodeHeader(value, key: key)
+        }
+    }
+
     /// Write dictionary key value pairs to headers with prefix added to the keys
     @inlinable
     public func encodeHeader(_ value: [String: some Any], key prefix: String) {
@@ -167,6 +175,20 @@ public class RequestEncodingContainer {
         }
     }
 
+    /// Write date to query
+    @inlinable
+    public func encodeQuery(_ value: Date, key: String) {
+        self.encodeQuery(UnixEpochDateCoder.string(from: value), key: key)
+    }
+
+    /// Write optional date to query
+    @inlinable
+    public func encodeQuery(_ value: Date?, key: String) {
+        if let value {
+            self.encodeQuery(value, key: key)
+        }
+    }
+
     /// Write array as a series of query values
     @inlinable
     public func encodeQuery(_ value: [some Any], key: String) {
@@ -199,6 +221,8 @@ public class RequestEncodingContainer {
         }
     }
 
+    // MARK: Path encoding
+
     /// Write value into URI path
     @inlinable
     public func encodePath(_ value: some Any, key: String) {

Tests/SotoCoreTests/AWSRequestTests.swift

@@ -328,6 +328,24 @@ class AWSRequestTests: XCTestCase {
         XCTAssertEqual(request?.url.absoluteString, "https://myservice.us-east-2.amazonaws.com/?one=1&two=2")
     }
 
+    func testQueryDate() {
+        struct Input: AWSEncodableShape {
+            let d: Date?
+            func encode(to encoder: Encoder) throws {
+                _ = encoder.container(keyedBy: CodingKeys.self)
+                let requestContainer = encoder.userInfo[.awsRequest]! as! RequestEncodingContainer
+                requestContainer.encodeQuery(self.d, key: "d")
+            }
+
+            private enum CodingKeys: CodingKey {}
+        }
+        let input = Input(d: Date(timeIntervalSince1970: 1_000_000))
+        let config = createServiceConfig(region: .useast2, service: "myservice")
+        var request: AWSHTTPRequest?
+        XCTAssertNoThrow(request = try AWSHTTPRequest(operation: "Test", path: "/", method: .GET, input: input, configuration: config))
+        XCTAssertEqual(request?.url.absoluteString, "https://myservice.us-east-2.amazonaws.com/?d=1000000")
+    }
+
     func testQueryInPath() {
         struct Input: AWSEncodableShape {
             let q: String