implement auto-discover function, close #66

README.md

@@ -24,12 +24,32 @@ int smtpServerPort = 465;
 bool isSmtpServerSecure = true;
 
 void main() async {
+  await discoverExample();
   await imapExample();
   await smtpExample();
   await popExample();
   exit(0);
 }
 
+Future<void> discoverExample() async {
+  var email = '[email protected]';
+  var config = await Discover.discover(email, isLogEnabled: false);
+  if (config == null) {
+    print('Unable to discover settings for $email');
+  } else {
+    print('Settings for $email:');
+    for (var provider in config.emailProviders) {
+      print('provider: ${provider.displayName}');
+      print('provider-domains: ${provider.domains}');
+      print('documentation-url: ${provider.documentationUrl}');
+      print('Incoming:');
+      print(provider.preferredIncomingServer);
+      print('Outgoing:');
+      print(provider.preferredOutgoingServer);
+    }
+  }
+}
+
 Future<void> imapExample() async {
   var client = ImapClient(isLogEnabled: false);
   await client.connectToServer(imapServerHost, imapServerPort,

example/enough_mail_example.dart

@@ -14,12 +14,38 @@ int smtpServerPort = 465;
 bool isSmtpServerSecure = true;
 
 void main() async {
+  await discoverExample();
   await imapExample();
   await smtpExample();
   await popExample();
   exit(0);
 }
 
+Future<void> discoverExample() async {
+  var email = '[email protected]';
+  var config = await Discover.discover(email, isLogEnabled: false);
+  if (config == null) {
+    print('Unable to discover settings for $email');
+  } else {
+    print('Settings for $email:');
+    for (var provider in config.emailProviders) {
+      print('provider: ${provider.displayName}');
+      print('provider-domains: ${provider.domains}');
+      print('documentation-url: ${provider.documentationUrl}');
+      print('Incoming:');
+      // for (var server in provider.incomingServers) {
+      //   print(server);
+      // }
+      print(provider.preferredIncomingServer);
+      print('Outgoing:');
+      // for (var server in provider.outgoingServers) {
+      //   print(server);
+      // }
+      print(provider.preferredOutgoingServer);
+    }
+  }
+}
+
 Future<void> imapExample() async {
   var client = ImapClient(isLogEnabled: false);
   await client.connectToServer(imapServerHost, imapServerPort,

lib/discover/client_config.dart

@@ -0,0 +1,139 @@
+class ClientConfig {
+  String version;
+  List<ConfigEmailProvider> emailProviders;
+
+  bool get isNotValid =>
+      emailProviders == null ||
+      emailProviders.isEmpty ||
+      emailProviders.first.preferredIncomingServer == null ||
+      emailProviders.first.preferredOutgoingServer == null;
+  bool get isValid => !isNotValid;
+
+  ClientConfig({this.version});
+
+  void addEmailProvider(ConfigEmailProvider provider) {
+    emailProviders ??= <ConfigEmailProvider>[];
+    emailProviders.add(provider);
+  }
+
+  ServerConfig get preferredIncomingServer => emailProviders?.isEmpty ?? true
+      ? null
+      : emailProviders.first.preferredIncomingServer;
+  ServerConfig get preferredIncomingImapServer =>
+      emailProviders?.isEmpty ?? true
+          ? null
+          : emailProviders.first.preferredIncomingImapServer;
+  ServerConfig get preferredIncomingPopServer => emailProviders?.isEmpty ?? true
+      ? null
+      : emailProviders.first.preferredIncomingPopServer;
+  ServerConfig get preferredOutgoingServer => emailProviders?.isEmpty ?? true
+      ? null
+      : emailProviders.first.preferredOutgoingServer;
+  ServerConfig get preferredOutgoingSmtpServer =>
+      emailProviders?.isEmpty ?? true
+          ? null
+          : emailProviders.first.preferredOutgoingSmtpServer;
+  String get displayName =>
+      emailProviders?.isEmpty ?? true ? null : emailProviders.first.displayName;
+}
+
+class ConfigEmailProvider {
+  String id;
+  List<String> domains;
+  String displayName;
+  String displayShortName;
+  List<ServerConfig> incomingServers;
+  List<ServerConfig> outgoingServers;
+  String documentationUrl;
+  ServerConfig preferredIncomingServer;
+  ServerConfig preferredIncomingImapServer;
+  ServerConfig preferredIncomingPopServer;
+  ServerConfig preferredOutgoingServer;
+  ServerConfig preferredOutgoingSmtpServer;
+
+  ConfigEmailProvider(
+      {this.id,
+      this.domains,
+      this.displayName,
+      this.displayShortName,
+      this.incomingServers,
+      this.outgoingServers});
+
+  void addDomain(String name) {
+    domains ??= <String>[];
+    domains.add(name);
+  }
+
+  void addIncomingServer(ServerConfig server) {
+    incomingServers ??= <ServerConfig>[];
+    incomingServers.add(server);
+    preferredIncomingServer ??= server;
+    if (server.type == ServerType.imap && preferredIncomingImapServer == null) {
+      preferredIncomingImapServer = server;
+    }
+    if (server.type == ServerType.pop && preferredIncomingPopServer == null) {
+      preferredIncomingPopServer = server;
+    }
+  }
+
+  void addOutgoingServer(ServerConfig server) {
+    outgoingServers ??= <ServerConfig>[];
+    outgoingServers.add(server);
+    preferredOutgoingServer ??= server;
+    if (server.type == ServerType.smtp && preferredOutgoingSmtpServer == null) {
+      preferredOutgoingSmtpServer = server;
+    }
+  }
+}
+
+enum ServerType { imap, pop, smtp, unknown }
+
+enum SocketType { plain, ssl, starttls, unknown }
+
+enum Authentication {
+  oauth2,
+  passwordCleartext,
+  plain,
+  passwordEncrypted,
+  secure,
+  ntlm,
+  gsapi,
+  clientIpAddress,
+  tlsClientCert,
+  smtpAfterPop,
+  none,
+  unknown
+}
+
+enum UsernameType { emailAddress, emailLocalPart, realname, unknown }
+
+class ServerConfig {
+  String typeName;
+  ServerType type;
+  String hostname;
+  int port;
+  SocketType socketType;
+  String get socketTypeName =>
+      socketType.toString().substring('socketType.'.length);
+  Authentication authentication;
+  Authentication authenticationAlternative;
+  String get authenticationName =>
+      authentication.toString().substring('authentication.'.length);
+  String username;
+  UsernameType usernameType;
+
+  bool get isSecureSocket => (socketType == SocketType.ssl);
+
+  ServerConfig(
+      {this.type,
+      this.hostname,
+      this.port,
+      this.socketType,
+      this.authentication,
+      this.username});
+
+  @override
+  String toString() {
+    return '$typeName:\n host: $hostname\n port: $port\n socket: $socketTypeName\n authentication: $authenticationName\n username: $username';
+  }
+}

lib/discover/discover.dart

@@ -0,0 +1,83 @@
+import 'package:enough_mail/src/util/discover_helper.dart';
+
+import 'client_config.dart';
+
+class Discover {
+  static Future<ClientConfig> discover(String emailAddress,
+      {bool forceSslConnection = false, bool isLogEnabled = false}) async {
+    var config = await _discover(emailAddress, isLogEnabled);
+    if (forceSslConnection && config != null) {
+      if (config.preferredIncomingImapServer != null &&
+          !config.preferredIncomingImapServer.isSecureSocket) {
+        config.preferredIncomingImapServer.port = 993;
+        config.preferredIncomingImapServer.socketType = SocketType.ssl;
+      }
+      if (config.preferredIncomingPopServer != null &&
+          !config.preferredIncomingPopServer.isSecureSocket) {
+        config.preferredIncomingPopServer.port = 995;
+        config.preferredIncomingPopServer.socketType = SocketType.ssl;
+      }
+      if (config.preferredOutgoingSmtpServer != null &&
+          !config.preferredOutgoingSmtpServer.isSecureSocket) {
+        config.preferredOutgoingSmtpServer.port = 465;
+        config.preferredOutgoingSmtpServer.socketType = SocketType.ssl;
+      }
+    }
+    return config;
+  }
+
+  static Future<ClientConfig> _discover(
+      String emailAddress, bool isLogEnabled) async {
+    // [1] autodiscover from sub-domain, compare: https://developer.mozilla.org/en-US/docs/Mozilla/Thunderbird/Autoconfiguration
+    var emailDomain = DiscoverHelper.getDomainFromEmail(emailAddress);
+    var config = await DiscoverHelper.discoverFromAutoConfigSubdomain(
+        emailAddress, emailDomain, isLogEnabled);
+    if (config != null) {
+      return _updateDisplayNames(config, emailDomain);
+    }
+    var mxDomain = await DiscoverHelper.discoverMxDomain(emailDomain);
+    _log('mxDomain for [$emailDomain] is [$mxDomain]', isLogEnabled);
+    if (mxDomain != null && mxDomain != emailDomain) {
+      config = await DiscoverHelper.discoverFromAutoConfigSubdomain(
+          emailAddress, mxDomain, isLogEnabled);
+      if (config != null) {
+        return _updateDisplayNames(config, emailDomain);
+      }
+    }
+    // TODO allow more autodiscover options:
+    // [2] https://docs.microsoft.com/en-us/previous-versions/office/office-2010/cc511507(v=office.14)
+    // [3] https://docs.microsoft.com/en-us/exchange/client-developer/exchange-web-services/autodiscover-for-exchange
+    // [4] https://docs.microsoft.com/en-us/exchange/architecture/client-access/autodiscover
+    // [6] by trying typical options like imap.$domain, mail.$domain, etc
+
+    //print('querying ISP DB for $mxDomain');
+
+    // [5] autodiscover from Mozilla ISP DB: https://developer.mozilla.org/en-US/docs/Mozilla/Thunderbird/Autoconfiguration
+    config = await DiscoverHelper.discoverFromIspDb(mxDomain, isLogEnabled);
+    //print('got config $config for $mxDomain.');
+    return _updateDisplayNames(config, emailDomain);
+  }
+
+  static ClientConfig _updateDisplayNames(
+      ClientConfig config, String mailDomain) {
+    if (config?.emailProviders?.isNotEmpty ?? false) {
+      for (var provider in config.emailProviders) {
+        if (provider.displayName != null) {
+          provider.displayName =
+              provider.displayName.replaceFirst('%EMAILDOMAIN%', mailDomain);
+        }
+        if (provider.displayShortName != null) {
+          provider.displayShortName = provider.displayShortName
+              .replaceFirst('%EMAILDOMAIN%', mailDomain);
+        }
+      }
+    }
+    return config;
+  }
+
+  static void _log(String text, bool isLogEnabled) {
+    if (isLogEnabled) {
+      print(text);
+    }
+  }
+}

lib/enough_mail.dart

@@ -21,6 +21,9 @@ export 'codecs/mail_codec.dart';
 export 'codecs/base64_mail_codec.dart';
 export 'codecs/quoted_printable_mail_codec.dart';
 
+export 'discover/client_config.dart';
+export 'discover/discover.dart';
+
 export 'mail_address.dart';
 export 'media_type.dart';
 export 'message_builder.dart';