Better Cookie Parsing (#2504) (#2511)

* still return cookies if some fail to parse values, and accept % in directive name

* added tests for cookie parsing

Sources/Vapor/HTTP/Headers/HTTPCookies.swift

@@ -3,7 +3,7 @@ extension HTTPHeaders {
     /// This accesses the `"Cookie"` header.
     public var cookie: HTTPCookies? {
         get {
-            self.parseDirectives(name: .cookie).first.flatMap {
+            self.parseDirectives(name: .cookie).first.map {
                 HTTPCookies(directives: $0)
             }
         }
@@ -238,14 +238,12 @@ public struct HTTPCookies: ExpressibleByDictionaryLiteral {
         self.cookies = [:]
     }
 
-    init?(directives: [HTTPHeaders.Directive]) {
-        self.cookies = [:]
-        for directive in directives {
-            guard let value = directive.parameter else {
-                return nil
+    init(directives: [HTTPHeaders.Directive]) {
+        self.cookies = directives.reduce(into: [:], { (cookies, directive) in
+            if let value = directive.parameter {
+                cookies[.init(directive.value)] = .init(string: .init(value))
             }
-            self.cookies[.init(directive.value)] = .init(string: .init(value))
-        }
+        })
     }
 
     /// See `ExpressibleByDictionaryLiteral`.

Sources/Vapor/HTTP/Headers/HTTPHeaders+Directive.swift

@@ -245,9 +245,12 @@ private extension Character {
     static var space: Self {
         .init(" ")
     }
+    static var percent: Self {
+        .init("%")
+    }
 
     var isDirectiveKey: Bool {
-        self.isLetter || self.isNumber || self == .dash || self == .underscore || self == .period
+        self.isLetter || self.isNumber || self == .dash || self == .underscore || self == .period || self == .percent
     }
 }
 

Tests/VaporTests/HTTPHeaderTests.swift

@@ -185,6 +185,27 @@ final class HTTPHeaderTests: XCTestCase {
         XCTAssertEqual(headers.cookie?["cookie_one"]?.string, "1")
         XCTAssertEqual(headers.cookie?["cookie.two"]?.string, "2")
     }
+
+    func testCookie_percentParsing() throws {
+        let headers = HTTPHeaders([
+            ("cookie", "cookie_one=1;cookie%40cookieCom=2;cookie_3=three")
+        ])
+
+        XCTAssertEqual(headers.cookie?["cookie_one"]?.string, "1")
+        XCTAssertEqual(headers.cookie?["cookie%40cookieCom"]?.string, "2")
+        XCTAssertEqual(headers.cookie?["cookie_3"]?.string, "three")
+    }
+
+    func testCookie_invalidCookie() throws {
+        let headers = HTTPHeaders([
+            ("cookie", "cookie_one=1;cookie\ntwo=2;cookie_three=3")
+        ])
+
+        XCTAssertEqual(headers.cookie?.all.count, 2)
+        XCTAssertEqual(headers.cookie?["cookie_one"]?.string, "1")
+        XCTAssertNil(headers.cookie?["cookie\ntwo"])
+        XCTAssertEqual(headers.cookie?["cookie_three"]?.string, "3")
+    }
 
     func testMediaTypeMainTypeCaseInsensitive() throws {
         let lower = HTTPMediaType(type: "foo", subType: "")