Polling causes memory leak by retaining request objects indefinitely

analysis_options.yaml

@@ -31,7 +31,7 @@ linter:
     - avoid_catching_errors
     - avoid_classes_with_only_static_members
     - avoid_double_and_int_checks
-    #- avoid_dynamic_calls
+    - avoid_dynamic_calls
     - avoid_empty_else
     - avoid_equals_and_hash_code_on_mutable_classes
     - avoid_escaping_inner_quotes
@@ -98,6 +98,7 @@ linter:
     - no_default_cases
     - no_duplicate_case_values
     - no_logic_in_create_state
+    - no_runtimeType_toString
     - non_constant_identifier_names
     - noop_primitive_operations
     - null_check_on_nullable_type_parameter

lib/src/coap_client.dart

@@ -516,7 +516,8 @@ class CoapClient {
     request
       ..observe = ObserveRegistration.register.value
       ..maxRetransmit = maxRetransmit;
-    final responseStream = _sendWithStreamResponse(request).asBroadcastStream();
+    final responseStream = _sendWithStreamResponse(request)
+        .asBroadcastStream(onCancel: (final sub) => sub.cancel());
     final relation = CoapObserveClientRelation(request, responseStream);
     final resp = await _waitForResponse(request, responseStream);
     if (!resp.hasOption<ObserveOption>()) {
@@ -543,7 +544,8 @@ class CoapClient {
     final CoapRequest request, {
     final CoapMulticastResponseHandler? onMulticastResponse,
   }) async {
-    final responseStream = _sendWithStreamResponse(request).asBroadcastStream();
+    final responseStream = _sendWithStreamResponse(request)
+        .asBroadcastStream(onCancel: (final sub) => sub.cancel());
     if (request.isMulticast) {
       if (onMulticastResponse == null) {
         throw ArgumentError('Missing onMulticastResponse argument');

lib/src/event/coap_event_bus.dart

@@ -25,7 +25,7 @@ abstract class CoapMessageEvent {
   CoapMessage msg;
 
   @override
-  String toString() => '$runtimeType: $msg';
+  String toString() => 'CoapMessageEvent: $msg';
 }
 
 abstract class CoapRequestEvent {
@@ -35,7 +35,7 @@ abstract class CoapRequestEvent {
   CoapRequest req;
 
   @override
-  String toString() => '$runtimeType: $req';
+  String toString() => 'CoapRequestEvent: $req';
 }
 
 abstract class CoapResponseEvent {
@@ -45,7 +45,7 @@ abstract class CoapResponseEvent {
   CoapResponse resp;
 
   @override
-  String toString() => '$runtimeType: $resp';
+  String toString() => 'CoapResponseEvent: $resp';
 }
 
 abstract class CoapExchangeEvent {
@@ -56,7 +56,7 @@ abstract class CoapExchangeEvent {
 
   @override
   String toString() =>
-      '$runtimeType:\nExchange for request ${exchange.request.id} '
+      'CoapExchangeEvent:\nExchange for request ${exchange.request.id} '
       "(token '${exchange.request.tokenString}')";
 }
 
@@ -158,15 +158,16 @@ class CoapMessageReceivedEvent {
   InternetAddress address;
 
   @override
-  String toString() => '$runtimeType:\n$coapMessage from ${address.address}';
+  String toString() =>
+      'CoapMessageReceivedEvent:\n$coapMessage from ${address.address}';
 }
 
 class CoapSocketInitEvent {
   /// Construction
   CoapSocketInitEvent();
 
   @override
-  String toString() => '$runtimeType:\nSocket attempting to initialize';
+  String toString() => 'CoapSocketInitEvent:\nSocket attempting to initialize';
 }
 
 class CoapSocketErrorEvent {
@@ -180,7 +181,7 @@ class CoapSocketErrorEvent {
   StackTrace stackTrace;
 
   @override
-  String toString() => '$runtimeType:\n$error\n$stackTrace';
+  String toString() => 'CoapSocketErrorEvent:\n$error\n$stackTrace';
 }
 
 /// Event bus class

lib/src/exceptions/coap_request_exception.dart

@@ -12,7 +12,7 @@ abstract class CoapRequestException implements Exception {
   CoapRequestException();
 
   @override
-  String toString() => '$runtimeType: $failReason';
+  String toString() => 'CoapRequestException: $failReason';
 }
 
 /// This [Exception] is thrown when a CoAP request has timed out.

lib/src/network/coap_inetwork.dart

@@ -23,8 +23,8 @@ class UnsupportedProtocolException implements Exception {
   UnsupportedProtocolException(this.uriScheme);
 
   @override
-  String toString() =>
-      '$runtimeType: Unsupported URI scheme $uriScheme encountered.';
+  String toString() => 'UnsupportedProtocolException: '
+      'Unsupported URI scheme $uriScheme encountered.';
 }
 
 /// Abstract networking class, allows different implementations for

lib/src/option/coap_block_option.dart

@@ -87,7 +87,7 @@ enum BlockOptionType {
 abstract class CoapBlockOption extends IntegerOption
     with OscoreOptionClassE, OscoreOptionClassU {
   String get _szxErrorMessage =>
-      'Encountered reserved SZX value 7 in $runtimeType.';
+      'Encountered reserved SZX value 7 in CoapBlockOption.';
 
   /// Base construction
   CoapBlockOption(

lib/src/option/coap_option_type.dart

@@ -29,7 +29,7 @@ abstract class UnknownOptionException implements Exception {
   UnknownOptionException(this.optionNumber, this.errorMessage);
 
   @override
-  String toString() => '$runtimeType:  $errorMessage';
+  String toString() => 'UnknownOptionException: $errorMessage';
 }
 
 /// [Exception] that is thrown when an unknown elective CoapOption number is

lib/src/stack/layers/reliability.dart

@@ -248,8 +248,7 @@ class _TransmissionContext {
     // Do not retransmit a message if it has been acknowledged,
     // rejected, canceled or already been retransmitted for the maximum
     // number of times.
-    if (!_message.isRejected &&
-        _message.isActive &&
+    if (_message.isActive &&
         failedTransmissionCount <=
             (_message.maxRetransmit != 0
                 ? _message.maxRetransmit

pubspec.yaml

@@ -11,22 +11,22 @@ environment:
   sdk: '>=3.0.0 <4.0.0'
 
 dependencies:
-  build: ^2.4.0
-  collection: ^1.17.2
+  build: ^2.4.1
+  collection: ^1.18.0
   convert: ^3.1.1
   dtls2: ^0.16.0
   event_bus: ^2.0.0
-  meta: ^1.9.0
-  path: ^1.8.3
+  meta: ^1.12.0
+  path: ^1.9.0
   string_scanner: ^1.2.0
   synchronized: ^3.1.0
   typed_data: ^1.3.2
   yaml: ^3.1.2
 
 dev_dependencies:
-  build_runner: ^2.4.7
+  build_runner: ^2.4.8
   lints: ^3.0.0
-  test: ^1.25.0
+  test: ^1.25.2
 
 topics:
   - iot