feat(auth): add getLinkIdentityURL (#342)

* feat: add `getLinkIdentityURL`

* test: add test for getLinkIdentityURL method

Author: Guilherme Souza

Examples/Examples/Profile/UserIdentityList.swift

@@ -10,6 +10,7 @@ import SwiftUI
 
 struct UserIdentityList: View {
   @Environment(\.webAuthenticationSession) private var webAuthenticationSession
+  @Environment(\.openURL) private var openURL
 
   @State private var identities = ActionState<[UserIdentity], any Error>.idle
   @State private var error: (any Error)?
@@ -61,22 +62,9 @@ struct UserIdentityList: View {
               Button(provider.rawValue) {
                 Task {
                   do {
-                    if #available(iOS 17.4, *) {
-                      let url = try await supabase.auth._getURLForLinkIdentity(provider: provider)
-                      let accessToken = try await supabase.auth.session.accessToken
-
-                      let callbackURL = try await webAuthenticationSession.authenticate(
-                        using: url,
-                        callback: .customScheme(Constants.redirectToURL.scheme!),
-                        preferredBrowserSession: .shared,
-                        additionalHeaderFields: ["Authorization": "Bearer \(accessToken)"]
-                      )
-
-                      debug("\(callbackURL)")
-                    } else {
-                      // Fallback on earlier versions
-                    }
-
+                    let response = try await supabase.auth.getLinkIdentityURL(provider: provider)
+                    openURL(response.url)
+                    debug("getLinkIdentityURL: \(response.url) opened for provider \(response.provider)")
                   } catch {
                     self.error = error
                   }

Examples/supabase/config.toml

@@ -53,6 +53,7 @@ jwt_expiry = 3600
 enable_signup = true
 # Allow/disallow testing manual linking of accounts
 enable_manual_linking = true
+enable_anonymous_sign_ins = true
 
 [auth.email]
 # Allow/disallow new user signups via email to your project.

Sources/Auth/AuthClient.swift

@@ -1068,28 +1068,43 @@ public final class AuthClient: @unchecked Sendable {
     try await user().identities ?? []
   }
 
-  /// Gets an URL that can be used for manual linking identity.
+  /// Returns the URL to link the user's identity with an OAuth provider.
+  ///
+  /// This method supports the PKCE flow.
+  ///
   /// - Parameters:
   ///   - provider: The provider you want to link the user with.
   ///   - scopes: The scopes to request from the OAuth provider.
   ///   - redirectTo: The redirect URL to use, specify a configured deep link.
   ///   - queryParams: Additional query parameters to use.
-  /// - Returns: A URL that you can use to initiate the OAuth flow.
-  ///
-  /// - Warning: This method is experimental and is expected to change.
-  public func _getURLForLinkIdentity(
+  public func getLinkIdentityURL(
     provider: Provider,
     scopes: String? = nil,
     redirectTo: URL? = nil,
     queryParams: [(name: String, value: String?)] = []
-  ) throws -> URL {
-    try getURLForProvider(
+  ) async throws -> OAuthResponse {
+    let url = try getURLForProvider(
       url: configuration.url.appendingPathComponent("user/identities/authorize"),
       provider: provider,
       scopes: scopes,
       redirectTo: redirectTo,
-      queryParams: queryParams
+      queryParams: queryParams,
+      skipBrowserRedirect: true
+    )
+
+    struct Response: Codable {
+      let url: URL
+    }
+
+    let response = try await api.authorizedExecute(
+      Request(
+        url: url,
+        method: .get
+      )
     )
+    .decoded(as: Response.self, decoder: configuration.decoder)
+
+    return OAuthResponse(provider: provider, url: response.url)
   }
 
   /// Unlinks an identity from a user by deleting it. The user will no longer be able to sign in
@@ -1202,7 +1217,8 @@ public final class AuthClient: @unchecked Sendable {
     provider: Provider,
     scopes: String? = nil,
     redirectTo: URL? = nil,
-    queryParams: [(name: String, value: String?)] = []
+    queryParams: [(name: String, value: String?)] = [],
+    skipBrowserRedirect: Bool? = nil
   ) throws -> URL {
     guard
       var components = URLComponents(
@@ -1234,6 +1250,10 @@ public final class AuthClient: @unchecked Sendable {
       queryItems.append(URLQueryItem(name: "code_challenge_method", value: codeChallengeMethod))
     }
 
+    if let skipBrowserRedirect {
+      queryItems.append(URLQueryItem(name: "skip_http_redirect", value: "\(skipBrowserRedirect)"))
+    }
+
     queryItems.append(contentsOf: queryParams.map(URLQueryItem.init))
 
     components.queryItems = queryItems

Sources/Auth/Types.swift

@@ -717,3 +717,8 @@ public struct SSOResponse: Codable, Hashable, Sendable {
   /// identity provider's authentication flow.
   public let url: URL
 }
+
+public struct OAuthResponse: Codable, Hashable, Sendable {
+  public let provider: Provider
+  public let url: URL
+}

Sources/_Helpers/Request.swift

@@ -78,11 +78,27 @@ package struct HTTPClient: Sendable {
 }
 
 package struct Request: Sendable {
-  public var path: String
-  public var method: Method
-  public var query: [URLQueryItem]
-  public var headers: [String: String]
-  public var body: Data?
+  enum _URL {
+    case absolute(url: URL)
+    case relative(path: String)
+
+    func resolve(withBaseURL baseURL: URL) -> URL {
+      switch self {
+      case let .absolute(url): url
+      case let .relative(path): baseURL.appendingPathComponent(path)
+      }
+    }
+  }
+
+  var _url: _URL
+  package var method: Method
+  package var query: [URLQueryItem]
+  package var headers: [String: String]
+  package var body: Data?
+
+  package func url(withBaseURL baseURL: URL) -> URL {
+    _url.resolve(withBaseURL: baseURL)
+  }
 
   package enum Method: String, Sendable {
     case get = "GET"
@@ -93,22 +109,8 @@ package struct Request: Sendable {
     case head = "HEAD"
   }
 
-  package init(
-    path: String,
-    method: Method,
-    query: [URLQueryItem] = [],
-    headers: [String: String] = [:],
-    body: Data? = nil
-  ) {
-    self.path = path
-    self.method = method
-    self.query = query
-    self.headers = headers
-    self.body = body
-  }
-
   package func urlRequest(withBaseURL baseURL: URL) throws -> URLRequest {
-    var url = baseURL.appendingPathComponent(path)
+    var url = url(withBaseURL: baseURL)
     if !query.isEmpty {
       guard var components = URLComponents(url: url, resolvingAgainstBaseURL: false) else {
         throw URLError(.badURL)
@@ -158,6 +160,40 @@ package struct Request: Sendable {
   }
 }
 
+extension Request {
+  package init(
+    path: String,
+    method: Method,
+    query: [URLQueryItem] = [],
+    headers: [String: String] = [:],
+    body: Data? = nil
+  ) {
+    self.init(
+      _url: .relative(path: path),
+      method: method,
+      query: query,
+      headers: headers,
+      body: body
+    )
+  }
+
+  package init(
+    url: URL,
+    method: Method,
+    query: [URLQueryItem] = [],
+    headers: [String: String] = [:],
+    body: Data? = nil
+  ) {
+    self.init(
+      _url: .absolute(url: url),
+      method: method,
+      query: query,
+      headers: headers,
+      body: body
+    )
+  }
+}
+
 extension CharacterSet {
   /// Creates a CharacterSet from RFC 3986 allowed characters.
   ///

Tests/AuthTests/AuthClientTests.swift

@@ -6,12 +6,12 @@
 //
 
 @testable import _Helpers
+@testable import Auth
 import ConcurrencyExtras
+import CustomDump
 import TestHelpers
 import XCTest
 
-@testable import Auth
-
 #if canImport(FoundationNetworking)
   import FoundationNetworking
 #endif
@@ -342,6 +342,32 @@ final class AuthClientTests: XCTestCase {
     }
   }
 
+  func testGetLinkIdentityURL() async throws {
+    api.execute = { @Sendable _ in
+      .stub(
+        """
+        {
+          "url" : "https://github.com/login/oauth/authorize?client_id=1234&redirect_to=com.supabase.swift-examples://&redirect_uri=http://127.0.0.1:54321/auth/v1/callback&response_type=code&scope=user:email&skip_http_redirect=true&state=jwt"
+        }
+        """
+      )
+    }
+
+    sessionManager.session = { @Sendable _ in .validSession }
+    codeVerifierStorage = .live
+    let sut = makeSUT()
+
+    let response = try await sut.getLinkIdentityURL(provider: .github)
+
+    XCTAssertNoDifference(
+      response,
+      OAuthResponse(
+        provider: .github,
+        url: URL(string: "https://github.com/login/oauth/authorize?client_id=1234&redirect_to=com.supabase.swift-examples://&redirect_uri=http://127.0.0.1:54321/auth/v1/callback&response_type=code&scope=user:email&skip_http_redirect=true&state=jwt")!
+      )
+    )
+  }
+
   private func makeSUT() -> AuthClient {
     let configuration = AuthClient.Configuration(
       url: clientURL,

Tests/AuthTests/RequestsTests.swift

@@ -406,6 +406,21 @@ final class RequestsTests: XCTestCase {
     }
   }
 
+  func testGetLinkIdentityURL() async {
+    sessionManager.session = { @Sendable _ in .validSession }
+
+    let sut = makeSUT()
+
+    await assert {
+      _ = try await sut.getLinkIdentityURL(
+        provider: .github,
+        scopes: "user:email",
+        redirectTo: URL(string: "https://supabase.com"),
+        queryParams: [("extra_key", "extra_value")]
+      )
+    }
+  }
+
   private func assert(_ block: () async throws -> Void) async {
     do {
       try await block()

Tests/AuthTests/__Snapshots__/RequestsTests/testGetLinkIdentityURL.1.txt

@@ -0,0 +1,5 @@
+curl \
+	--header "Apikey: dummy.api.key" \
+	--header "Authorization: Bearer accesstoken" \
+	--header "X-Client-Info: gotrue-swift/x.y.z" \
+	"http://localhost:54321/auth/v1/user/identities/authorize?extra_key=extra_value&provider=github&redirect_to=https://supabase.com&scopes=user:email&skip_http_redirect=true"