Merge pull request #8 from nodes-vapor/percent-encoder

Percent Encoder

Author: BrettRToomey

Sources/Driver/Authentication/Authentication.swift

@@ -23,14 +23,6 @@ struct Authentication {
 
     //used for unit tests
     var unitTestDate: Date?
-
-    static let awsQueryAllowed = CharacterSet(
-        charactersIn: "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-._~="
-    )
-    
-    static let awsPathAllowed = CharacterSet(
-        charactersIn: "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-._~/"
-    )
 
     var amzDate: String {
         let dateFormatter = DateFormatter()
@@ -54,14 +46,10 @@ struct Authentication {
         self.host = host
         self.region = region
         //TODO(Brett): Proper encoding and error handling.
-        self.baseURL = baseURL.addingPercentEncoding(
-            withAllowedCharacters: Authentication.awsPathAllowed
-        )!
+        self.baseURL = try! baseURL.percentEncode(allowing: Byte.awsPathAllowed)
         self.key = key
         self.secret = secret
-        self.requestParam = requestParam?.addingPercentEncoding(
-            withAllowedCharacters: Authentication.awsQueryAllowed
-        )
+        self.requestParam = try! requestParam?.percentEncode(allowing: Byte.awsQueryAllowed)
     }
 
     func getSignature(stringToSign: String) throws -> String {

Sources/Driver/PercentEncoder.swift

@@ -0,0 +1,37 @@
+import Core
+
+extension Byte {
+    static let awsQueryAllowed = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-._~=".bytes
+    
+    static let awsPathAllowed  = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-._~/".bytes
+}
+
+extension String {
+    func percentEncode(allowing allowed: Bytes) throws -> String {
+        let bytes = self.bytes
+        let encodedBytes = try percentEncodedUppercase(bytes, shouldEncode: {
+            return !allowed.contains($0)
+        })
+        return encodedBytes.string
+    }
+}
+
+func percentEncodedUppercase(
+    _ input: [Byte],
+    shouldEncode: (Byte) throws -> Bool = { _ in true }
+) throws -> [Byte] {
+    var group: [Byte] = []
+    try input.forEach { byte in
+        if try shouldEncode(byte) {
+            let hex = String(byte, radix: 16).uppercased().utf8
+            group.append(.percent)
+            if hex.count == 1 {
+                group.append(.zero)
+            }
+            group.append(contentsOf: hex)
+        } else {
+            group.append(byte)
+        }
+    }
+    return group
+}