Merge pull request #25 from Yasumoto/autoscaling_apis

Add support for AutoScaling API

Author: BrettRToomey

Package.swift

@@ -3,12 +3,14 @@ import PackageDescription
 let package = Package(
     name: "AWS",
     targets: [
-        Target(name: "AWS", dependencies: ["EC2", "S3", "AWSSignatureV4"]),
+        Target(name: "AWS", dependencies: ["AutoScaling", "EC2", "S3", "AWSSignatureV4"]),
         Target(name: "EC2", dependencies: ["AWSSignatureV4"]),
+        Target(name: "AutoScaling", dependencies: ["AWSSignatureV4"]),
         Target(name: "S3", dependencies: ["AWSSignatureV4"]),
         Target(name: "VaporS3", dependencies: ["S3"]),
     ],
     dependencies: [
         .Package(url: "https://github.com/vapor/vapor.git", majorVersion: 2),
+        .Package(url: "https://github.com/drmohundro/SWXMLHash", majorVersion: 3),
     ]
 )

README.md

@@ -83,6 +83,13 @@ do {
 }
 ```
 
+## 📃 Development
+
+If you want to improve this, you'll need to make sure you're making a copy of OpenSSL available to `swift build` and the toolchain. If you use Xcode, something like the following after `brew install openssl` will work:
+
+```
+swift package -Xswiftc -I/usr/local/Cellar/openssl/1.0.2j/include -Xlinker -L/usr/local/Cellar/openssl/1.0.2j/lib/ generate-xcodeproj
+```
 
 ## 🏆 Credits
 

Sources/AWSSignatureV4/AWSSignatureV4.swift

@@ -20,15 +20,16 @@ public struct AWSSignatureV4 {
         case post = "POST"
         case put = "PUT"
     }
-    
+
     let service: String
     let host: String
     let region: String
     let accessKey: String
     let secretKey: String
-    
-    var unitTestDate: Date?
-    
+    let contentType = "application/x-www-form-urlencoded; charset=utf-8"
+
+    internal var unitTestDate: Date?
+
     var amzDate: String {
         let dateFormatter = DateFormatter()
         dateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
@@ -63,7 +64,7 @@ public struct AWSSignatureV4 {
             canonicalHash
         ].joined(separator: "\n")
     }
-    
+
     func getSignature(_ stringToSign: String) throws -> String {
         let dateHMAC = try HMAC(.sha256, dateStamp()).authenticate(key: "AWS4\(secretKey)")
         let regionHMAC = try HMAC(.sha256, region).authenticate(key: dateHMAC)
@@ -82,7 +83,7 @@ public struct AWSSignatureV4 {
             "aws4_request"
         ].joined(separator: "/")
     }
-    
+
     func getCanonicalRequest(
         payloadHash: String,
         method: Method,
@@ -93,7 +94,7 @@ public struct AWSSignatureV4 {
     ) throws -> String {
         let path = try path.percentEncode(allowing: Byte.awsPathAllowed)
         let query = try query.percentEncode(allowing: Byte.awsQueryAllowed)
-        
+
         return [
             method.rawValue,
             path,
@@ -108,6 +109,7 @@ public struct AWSSignatureV4 {
     func dateStamp() -> String {
         let date = unitTestDate ?? Date()
         let dateFormatter = DateFormatter()
+        dateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
         dateFormatter.dateFormat = "YYYYMMdd"
         return dateFormatter.string(from: date)
     }
@@ -119,24 +121,24 @@ extension AWSSignatureV4 {
         host: String,
         hash: String
     ) {
-        headers["host"] = host
+        headers["Host"] = host
         headers["X-Amz-Date"] = amzDate
-        
-        if hash != "UNSIGNED-PAYLOAD" {
+
+         if hash != "UNSIGNED-PAYLOAD" {
             headers["x-amz-content-sha256"] = hash
         }
     }
-    
+
     func alphabetize(_ dict: [String : String]) -> [(key: String, value: String)] {
         return dict.sorted(by: { $0.0.lowercased() < $1.0.lowercased() })
     }
-    
+
     func createCanonicalHeaders(_ headers: [(key: String, value: String)]) -> String {
         return headers.map {
             "\($0.key.lowercased()):\($0.value)"
         }.joined(separator: "\n")
     }
-    
+
     func createAuthorizationHeader(
         algorithm: String,
         credentialScope: String,
@@ -148,6 +150,19 @@ extension AWSSignatureV4 {
 }
 
 extension AWSSignatureV4 {
+    /**
+    Sign a request to be sent to an AWS API.
+
+    - returns:
+    A dictionary with headers to attach to a request
+
+    - parameters:
+        - payload: A hash of this data will be included in the headers
+        - method: Type of HTTP request
+        - path: API call being referenced
+        - query: Additional querystring in key-value format ("?key=value&key2=value2")
+        - headers: HTTP headers added to the request
+    */
     public func sign(
         payload: Payload = .none,
         method: Method = .get,
@@ -158,14 +173,16 @@ extension AWSSignatureV4 {
         let algorithm = "AWS4-HMAC-SHA256"
         let credentialScope = getCredentialScope()
         let payloadHash = try payload.hashed()
-        
+
         var headers = headers
+
         generateHeadersToSign(headers: &headers, host: host, hash: payloadHash)
-        
+
         let sortedHeaders = alphabetize(headers)
         let signedHeaders = sortedHeaders.map { $0.key.lowercased() }.joined(separator: ";")
         let canonicalHeaders = createCanonicalHeaders(sortedHeaders)
-        
+
+        // Task 1 is the Canonical Request
         let canonicalRequest = try getCanonicalRequest(
             payloadHash: payloadHash,
             method: method,
@@ -176,35 +193,39 @@ extension AWSSignatureV4 {
         )
 
         let canonicalHash = try Hash.make(.sha256, canonicalRequest).hexString
-        
+
+        // Task 2 is the String to Sign
         let stringToSign = getStringToSign(
             algorithm: algorithm,
             date: amzDate,
             scope: credentialScope,
             canonicalHash: canonicalHash
         )
-        
+
+        // Task 3 calculates Signature
         let signature = try getSignature(stringToSign)
-        
+
+        //Task 4 Add signing information to the request
         let authorizationHeader = createAuthorizationHeader(
             algorithm: algorithm,
             credentialScope: credentialScope,
             signature: signature,
             signedHeaders: signedHeaders
         )
-      
-      
+
         var requestHeaders: [HeaderKey: String] = [
             "X-Amz-Date": amzDate,
+            "Content-Type": contentType,
             "x-amz-content-sha256": payloadHash,
-            "Authorization": authorizationHeader
+            "Authorization": authorizationHeader,
+            "Host": self.host
         ]
-      
+
         headers.forEach { key, value in
             let headerKey = HeaderKey(stringLiteral: key)
             requestHeaders[headerKey] = value
         }
-      
+
         return requestHeaders
     }
 }

Sources/AWSSignatureV4/ErrorParser/ErrorParser+Grammar.swift

@@ -3,7 +3,7 @@ import Core
 extension ErrorParser {
     static let awsGrammar: Trie<AWSError> = {
         let trie = Trie<AWSError>()
-        
+
         insert(into: trie, .accessDenied)
         insert(into: trie, .accountProblem)
         insert(into: trie, .ambiguousGrantByEmailAddress)
@@ -82,10 +82,10 @@ extension ErrorParser {
         insert(into: trie, .unexpectedContent)
         insert(into: trie, .unresolvableGrantByEmailAddress)
         insert(into: trie, .userKeyMustBeSpecified)
-        
+
         return trie
     }()
-    
+
     static func insert(into trie: Trie<AWSError>, _ error: AWSError) {
         trie.insert(error, for: error.rawValue.makeBytes())
     }

Sources/AWSSignatureV4/ErrorParser/ErrorParser.swift

@@ -6,9 +6,9 @@ public struct ErrorParser {
         case unknownError(String)
         case couldNotFindErrorTag
     }
-    
+
     var scanner: Scanner<Byte>
-    
+
     init(scanner: Scanner<Byte>) {
         self.scanner = scanner
     }
@@ -25,29 +25,29 @@ extension ErrorParser {
     mutating func extractError() throws -> AWSError {
         while true {
             skip(until: .lessThan)
-            
+
             guard scanner.peek() != nil else {
                 throw Error.couldNotFindErrorTag
             }
-            
+
             // check for `<Code>`
             guard checkForCodeTag() else {
                 continue
             }
-            
+
             let errorBytes = consume(until: .lessThan)
-            
+
             guard let error = ErrorParser.awsGrammar.contains(errorBytes) else {
                 throw Error.unknownError(errorBytes.makeString())
             }
-            
+
             return error
         }
     }
-    
+
     mutating func checkForCodeTag() -> Bool {
         scanner.pop()
-        
+
         for (index, byte) in ErrorParser.codeBytes.enumerated() {
             guard
                 let preview = scanner.peek(aheadBy: index),
@@ -56,49 +56,49 @@ extension ErrorParser {
                     return false
             }
         }
-        
+
         scanner.pop(ErrorParser.codeBytes.count)
-        
+
         return true
     }
 }
 
 extension ErrorParser {
     mutating func skip(until terminator: Byte) {
         var count = 0
-        
+
         while let byte = scanner.peek(aheadBy: count), byte != terminator {
             count += 1
         }
-        
+
         scanner.pop(count)
     }
-    
+
     mutating func consume(until terminator: Byte) -> Bytes {
         var bytes: [Byte] = []
-        
+
         while let byte = scanner.peek(), byte != terminator {
             scanner.pop()
             bytes.append(byte)
         }
-        
+
         return bytes
     }
 }
 
 extension Byte {
     /// <
     static let lessThan: Byte = 0x3C
-    
+
     /// >
     static let greaterThan: Byte = 0x3E
-    
+
     /// lowercase `d`
     static let d: Byte = 0x64
-    
+
     /// lowercase `e`
     static let e: Byte = 0x65
-    
+
     /// lowercase `o`
     static let o: Byte = 0x6F
 }

Sources/AWSSignatureV4/ErrorParser/Scanner.swift

@@ -9,7 +9,7 @@ extension Scanner {
     init(_ data: [Element]) {
         self.elementsCopy = data
         self.elements = elementsCopy.withUnsafeBufferPointer { $0 }
-        
+
         self.pointer = elements.baseAddress!
     }
 }
@@ -19,23 +19,23 @@ extension Scanner {
         guard pointer.advanced(by: n) < elements.endAddress else { return nil }
         return pointer.advanced(by: n).pointee
     }
-    
+
     /// - Precondition: index != bytes.endIndex. It is assumed before calling pop that you have
     @discardableResult
     mutating func pop() -> Element {
         assert(pointer != elements.endAddress)
         defer { pointer = pointer.advanced(by: 1) }
         return pointer.pointee
     }
-    
+
     /// - Precondition: index != bytes.endIndex. It is assumed before calling pop that you have
     @discardableResult
     mutating func attemptPop() throws -> Element {
         guard pointer < elements.endAddress else { throw ScannerError.Reason.endOfStream }
         defer { pointer = pointer.advanced(by: 1) }
         return pointer.pointee
     }
-    
+
     mutating func pop(_ n: Int) {
         for _ in 0..<n {
             pop()
@@ -52,7 +52,7 @@ extension Scanner {
 struct ScannerError: Swift.Error {
     let position: UInt
     let reason: Reason
-    
+
     enum Reason: Swift.Error {
         case endOfStream
     }