#54 Public account type

Example/DApp/ClientDelegate.swift

@@ -31,7 +31,7 @@ class ClientDelegate: WalletConnectClientDelegate {
         onSessionResponse?(sessionResponse)
     }
 
-    func didUpdate(sessionTopic: String, accounts: Set<String>) {
+    func didUpdate(sessionTopic: String, accounts: Set<Account>) {
     }
 
     func didUpgrade(sessionTopic: String, permissions: Session.Permissions) {

Example/ExampleApp/Responder/ResponderViewController.swift

@@ -150,8 +150,8 @@ extension ResponderViewController: SessionViewControllerDelegate {
         print("[RESPONDER] Approving session...")
         let proposal = currentProposal!
         currentProposal = nil
-        let accounts = proposal.permissions.blockchains.map {$0+":\(account)"}
-        client.approve(proposal: proposal, accounts: Set(accounts))
+        let accounts = Set(proposal.permissions.blockchains.compactMap { Account($0+":\(account)") })
+        client.approve(proposal: proposal, accounts: accounts)
     }
 
     func didRejectSession() {
@@ -196,7 +196,7 @@ extension ResponderViewController: WalletConnectClientDelegate {
 
     }
 
-    func didUpdate(sessionTopic: String, accounts: Set<String>) {
+    func didUpdate(sessionTopic: String, accounts: Set<Account>) {
 
     }
 

Sources/WalletConnect/Account.swift

@@ -0,0 +1,94 @@
+/**
+ A value that identifies an account in any given blockchain.
+
+ This structure parses account IDs according to [CAIP-10].
+ Account IDs are prefixed with a [CAIP-2] blockchain ID, delimited by a `':'` character, followed by the account address.
+
+ Specifying a blockchain account by using a chain-agnostic identifier is useful to allow interoperability between multiple
+ chains when using both wallets and decentralized applications.
+
+ [CAIP-2]:https://github.com/ChainAgnostic/CAIPs/blob/master/CAIPs/caip-2.md
+ [CAIP-10]:https://github.com/ChainAgnostic/CAIPs/blob/master/CAIPs/caip-10.md
+ */
+public struct Account: Equatable, Hashable {
+
+    /// A blockchain namespace. Usually describes an ecosystem or standard.
+    public let namespace: String
+
+    /// A reference string that identifies a blockchain within a given namespace.
+    public let reference: String
+
+    /// The account's address specific to the blockchain.
+    public let address: String
+
+    /// The CAIP-2 blockchain identifier of the account.
+    public var blockchainIdentifier: String {
+        "\(namespace):\(reference)"
+    }
+
+    /// The CAIP-10 account identifier absolute string.
+    public var absoluteString: String {
+        "\(namespace):\(reference):\(address)"
+    }
+
+    /// Returns whether the account conforms to CAIP-10.
+    public var isCAIP10Conformant: Bool {
+        String.conformsToCAIP10(absoluteString)
+    }
+
+    /**
+     Creates an account instance from the provided string.
+
+     This initializer returns nil if the string doesn't represent a valid account id in conformance with
+     [CAIP-10](https://github.com/ChainAgnostic/CAIPs/blob/master/CAIPs/caip-10.md).
+     */
+    public init?(_ string: String) {
+        guard String.conformsToCAIP10(string) else { return nil }
+        let splits = string.split(separator: ":")
+        self.init(namespace: String(splits[0]), reference: String(splits[1]), address: String(splits[2]))
+    }
+
+    /**
+     Creates an account instance from a chain ID and an address.
+
+     This initializer returns nil if the `chainIdentifier` parameter doesn't represent a valid chain id in conformance with
+     [CAIP-2](https://github.com/ChainAgnostic/CAIPs/blob/master/CAIPs/caip-2.md) or if the `address` format is invalid.
+     */
+    public init?(chainIdentifier: String, address: String) {
+        self.init("\(chainIdentifier):\(address)")
+    }
+
+    /**
+     Creates an account instance directly from the base components.
+
+     This initializer bypass any checks to CAIP conformance, make sure to pass valid values as parameters.
+     */
+    public init(namespace: String, reference: String, address: String) {
+        self.namespace = namespace
+        self.reference = reference
+        self.address = address
+    }
+}
+
+extension Account: LosslessStringConvertible {
+    public var description: String {
+        return absoluteString
+    }
+}
+
+extension Account: Codable {
+
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        let absoluteString = try container.decode(String.self)
+        guard let account = Account(absoluteString) else {
+            throw DecodingError.dataCorruptedError(in: container, debugDescription: "Malformed CAIP-10 account identifier.")
+        }
+        self = account
+    }
+
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        try container.encode(absoluteString)
+    }
+}

Sources/WalletConnect/WalletConnectClient.swift

@@ -137,8 +137,8 @@ public final class WalletConnectClient {
     /// - Parameters:
     ///   - proposal: Session Proposal received from peer client in a WalletConnect delegate function: `didReceive(sessionProposal: Session.Proposal)`
     ///   - accounts: A Set of accounts that the dapp will be allowed to request methods executions on.
-    public func approve(proposal: Session.Proposal, accounts: Set<String>) {
-        sessionEngine.approve(proposal: proposal.proposal, accounts: accounts)
+    public func approve(proposal: Session.Proposal, accounts: Set<Account>) {
+        sessionEngine.approve(proposal: proposal.proposal, accounts: Set(accounts.map { $0.absoluteString }))
     }
 
     /// For the responder to reject a session proposal.
@@ -153,12 +153,8 @@ public final class WalletConnectClient {
     /// - Parameters:
     ///   - topic: Topic of the session that is intended to be updated.
     ///   - accounts: Set of accounts that will be allowed to be used by the session after the update.
-    public func update(topic: String, accounts: Set<String>) {
-        do {
-            try sessionEngine.update(topic: topic, accounts: accounts)
-        } catch {
-            print("Error on session update call: \(error)")
-        }
+    public func update(topic: String, accounts: Set<Account>) throws {
+        try sessionEngine.update(topic: topic, accounts: Set(accounts.map { $0.absoluteString }))
     }
 
     /// For the responder to upgrade session permissions
@@ -305,7 +301,7 @@ public final class WalletConnectClient {
             delegate?.didUpgrade(sessionTopic: topic, permissions: upgradedPermissions)
         }
         sessionEngine.onSessionUpdate = { [unowned self] topic, accounts in
-            delegate?.didUpdate(sessionTopic: topic, accounts: accounts)
+            delegate?.didUpdate(sessionTopic: topic, accounts: Set(accounts.compactMap { Account($0) }))
         }
         sessionEngine.onNotificationReceived = { [unowned self] topic, notification in
             delegate?.didReceive(notification: notification, sessionTopic: topic)

Sources/WalletConnect/WalletConnectClientDelegate.swift

@@ -36,7 +36,7 @@ public protocol WalletConnectClientDelegate: AnyObject {
     /// Tells the delegate that extra accounts has been included in session sequence
     ///
     /// Function is executed on controller and non-controller client when both communicating peers have successfully included new accounts requested by the controller client.
-    func didUpdate(sessionTopic: String, accounts: Set<String>)
+    func didUpdate(sessionTopic: String, accounts: Set<Account>)
 
     /// Tells the delegate that the client has settled a session.
     ///

Tests/IntegrationTests/ClientDelegate.swift

@@ -12,7 +12,7 @@ class ClientDelegate: WalletConnectClientDelegate {
     var onSessionRejected: ((String, Reason)->())?
     var onSessionDelete: (()->())?
     var onSessionUpgrade: ((String, Session.Permissions)->())?
-    var onSessionUpdate: ((String, Set<String>)->())?
+    var onSessionUpdate: ((String, Set<Account>)->())?
     var onNotificationReceived: ((Session.Notification, String)->())?
     var onPairingUpdate: ((String, AppMetadata)->())?
 
@@ -42,7 +42,7 @@ class ClientDelegate: WalletConnectClientDelegate {
     func didUpgrade(sessionTopic: String, permissions: Session.Permissions) {
         onSessionUpgrade?(sessionTopic, permissions)
     }
-    func didUpdate(sessionTopic: String, accounts: Set<String>) {
+    func didUpdate(sessionTopic: String, accounts: Set<Account>) {
         onSessionUpdate?(sessionTopic, accounts)
     }
     func didReceive(notification: Session.Notification, sessionTopic: String) {

Tests/IntegrationTests/ClientTest.swift

@@ -56,7 +56,7 @@ final class ClientTests: XCTestCase {
     func testNewSession() {
         let proposerSettlesSessionExpectation = expectation(description: "Proposer settles session")
         let responderSettlesSessionExpectation = expectation(description: "Responder settles session")
-        let account = "0x022c0c42a80bd19EA4cF0F94c4F9F96645759716"
+        let account = Account("eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb")!
 
         let permissions = Session.Permissions.stub()
         let uri = try! proposer.client.connect(sessionPermissions: permissions)!
@@ -244,7 +244,7 @@ final class ClientTests: XCTestCase {
     func testSuccessfulSessionUpgrade() {
         let proposerSessionUpgradeExpectation = expectation(description: "Proposer upgrades session on responder request")
         let responderSessionUpgradeExpectation = expectation(description: "Responder upgrades session on proposer response")
-        let account = "0x022c0c42a80bd19EA4cF0F94c4F9F96645759716"
+        let account = Account("eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb")!
         let permissions = Session.Permissions.stub()
         let upgradePermissions = Session.Permissions(blockchains: ["eip155:42"], methods: ["eth_sendTransaction"])
         let uri = try! proposer.client.connect(sessionPermissions: permissions)!
@@ -271,16 +271,16 @@ final class ClientTests: XCTestCase {
     func testSuccessfulSessionUpdate() {
         let proposerSessionUpdateExpectation = expectation(description: "Proposer updates session on responder request")
         let responderSessionUpdateExpectation = expectation(description: "Responder updates session on proposer response")
-        let account = "eip155:42:0x022c0c42a80bd19EA4cF0F94c4F9F96645759716"
-        let updateAccounts: Set<String> = ["eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb"]
+        let account = Account("eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb")!
+        let updateAccounts: Set<Account> = [Account("eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdf")!]
         let permissions = Session.Permissions.stub()
         let uri = try! proposer.client.connect(sessionPermissions: permissions)!
         try! responder.client.pair(uri: uri)
         responder.onSessionProposal = { [unowned self] proposal in
             self.responder.client.approve(proposal: proposal, accounts: [account])
         }
         responder.onSessionSettled = { [unowned self] sessionSettled in
-            responder.client.update(topic: sessionSettled.topic, accounts: updateAccounts)
+            try? responder.client.update(topic: sessionSettled.topic, accounts: updateAccounts)
         }
         responder.onSessionUpdate = { _, accounts in
             XCTAssertEqual(accounts, updateAccounts)

Tests/WalletConnectTests/AccountTests.swift

@@ -0,0 +1,52 @@
+import XCTest
+@testable import WalletConnect
+
+final class AccountTests: XCTestCase {
+
+    func testInitFromString() {
+        // Valid accounts
+        XCTAssertNotNil(Account("std:0:0"))
+        XCTAssertNotNil(Account("chainstd:8c3444cf8970a9e41a706fab93e7a6c4:6d9b0b4b9994e8a6afbd3dc3ed983cd51c755afb27cd1dc7825ef59c134a39f7"))
+
+        // Invalid accounts
+        XCTAssertNil(Account("std:0:$"))
+        XCTAssertNil(Account("std:$:0"))
+        XCTAssertNil(Account("st:0:0"))
+    }
+
+    func testInitFromChainAndAddress() {
+        // Valid accounts
+        XCTAssertNotNil(Account(chainIdentifier: "std:0", address: "0"))
+        XCTAssertNotNil(Account(chainIdentifier: "chainstd:8c3444cf8970a9e41a706fab93e7a6c4", address: "6d9b0b4b9994e8a6afbd3dc3ed983cd51c755afb27cd1dc7825ef59c134a39f7"))
+
+        // Invalid accounts
+        XCTAssertNil(Account(chainIdentifier: "std:0", address: ""))
+        XCTAssertNil(Account(chainIdentifier: "std", address: "0"))
+    }
+
+    func testInitCAIP10Conformance() {
+        XCTAssertTrue(Account(namespace: "std", reference: "0", address: "0").isCAIP10Conformant)
+
+        XCTAssertFalse(Account(namespace: "st", reference: "0", address: "0").isCAIP10Conformant)
+        XCTAssertFalse(Account(namespace: "std", reference: "", address: "0").isCAIP10Conformant)
+        XCTAssertFalse(Account(namespace: "std", reference: "0", address: "").isCAIP10Conformant)
+    }
+
+    func testBlockchainIdentifier() {
+        let account = Account("eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb")!
+        XCTAssertEqual(account.blockchainIdentifier, "eip155:1")
+    }
+
+    func testAbsoluteString() {
+        let accountString = "eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb"
+        let account = Account(accountString)!
+        XCTAssertEqual(account.absoluteString, accountString)
+    }
+
+    func testCodable() throws {
+        let account = Account("eip155:1:0xab16a96d359ec26a11e2c2b3d8f8b8942d5bfcdb")!
+        let encoded = try JSONEncoder().encode(account)
+        let decoded = try JSONDecoder().decode(Account.self, from: encoded)
+        XCTAssertEqual(account, decoded)
+    }
+}