chore: added full error set and ran linter

lib/src/errors/errors.dart

@@ -1,29 +1,259 @@
+import 'package:grpc/grpc.dart';
+
 enum MomentoErrorCode {
+  /// Invalid argument passed to Momento client
   invalidArgumentError,
+
+  /// Service returned an unknown response
   unknownServiceError,
+
+  /// Resource with specified name already exists
   alreadyExistsError,
+
+  /// Cache with specified name doesn't exist
   notFoundError,
+
+  /// An unexpected error occurred while trying to fulfill the request
+  internalServerError,
+
+  /// Insufficient permissions to perform operation
+  permissionError,
+
+  /// Invalid authentication credentials to connect to service
+  authenticationError,
+
+  /// Request was cancelled by the server
+  cancelledError,
+
+  /// Request rate, bandwidth, or object size exceeded the limits for the account
+  limitExceededError,
+
+  /// Request was invalid
+  badRequestError,
+
+  /// Client's configured timeout was exceeded
+  timeoutError,
+
+  /// Server was unable to handle the request
+  serverUnavailable,
+
+  /// A client resource (most likely memory) was exhausted
+  clientResourceExhausted,
+
+  /// System is not in a state required for the operation's execution
+  failedPreconditionError,
+}
+
+class MomentoErrorTransportDetails {
+  final MomentoGrpcErrorDetails _grpc;
+
+  MomentoErrorTransportDetails(this._grpc);
+
+  MomentoGrpcErrorDetails get grpc => _grpc;
+}
+
+class MomentoGrpcErrorDetails {
+  final Code _code;
+  final String _details;
+  final GrpcMetadata? _metadata;
+
+  MomentoGrpcErrorDetails(this._code, this._details, this._metadata);
+
+  Code get code => _code;
+  String get details => _details;
+  GrpcMetadata? get metadata => _metadata;
 }
 
 abstract class AbstractExceptionResponseBase {
+  /// Detailed information about the exception
   final String _message;
+
+  /// Error code corresponding to one of the values of `MomentoErrorCode`
+  final MomentoErrorCode _errorCode;
+
+  /// Original `Exception`, if any, from which the `SdkException` was created
   final Exception? _innerException;
-  AbstractExceptionResponseBase(this._message, this._innerException);
+
+  AbstractExceptionResponseBase(
+      this._message, this._errorCode, this._innerException);
 
   String get message => _message;
+  MomentoErrorCode get errorCode => _errorCode;
   Exception? get innerException => _innerException;
 }
 
 class SdkException extends AbstractExceptionResponseBase implements Exception {
   final String _messageWrapper;
-  SdkException(String message, Exception? innerException, String messageWrapper)
-      : _messageWrapper = messageWrapper,
-        super(message, innerException);
+  final MomentoErrorTransportDetails? _transportDetails;
+
+  SdkException(String message, MomentoErrorCode errorCode,
+      Exception? innerException, this._messageWrapper, this._transportDetails)
+      : super(message, errorCode, innerException);
 
   String get messageWrapper => _messageWrapper;
+  MomentoErrorTransportDetails? get transportDetails => _transportDetails;
 }
 
+/// Invalid argument passed to Momento client
+class InvalidArgumentException extends SdkException {
+  InvalidArgumentException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(message, MomentoErrorCode.invalidArgumentError, innerException,
+            "Invalid argument passed to Momento client:", transportDetails);
+}
+
+/// Service returned an unknown response
 class UnknownException extends SdkException {
-  UnknownException(String message, Exception? innerException)
-      : super(message, innerException, "Unknown error has occurred");
+  UnknownException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.unknownServiceError,
+            innerException,
+            "The service returned an unknown response; please contact Momento.",
+            transportDetails);
+}
+
+/// Resource with specified name already exists
+class AlreadyExistsException extends SdkException {
+  AlreadyExistsException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.alreadyExistsError,
+            innerException,
+            "A cache with the specified name already exists.  To resolve this error, either delete the existing cache and make a new one, or use a different name.",
+            transportDetails);
+}
+
+/// Cache with specified name doesn't exist
+class NotFoundException extends SdkException {
+  NotFoundException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.notFoundError,
+            innerException,
+            "A cache with the specified name does not exist.  To resolve this error, make sure you have created the cache before attempting to use it.",
+            transportDetails);
+}
+
+/// An unexpected error occurred while trying to fulfill the request
+class InternalServerException extends SdkException {
+  InternalServerException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.internalServerError,
+            innerException,
+            "An unexpected error occurred while trying to fulfill the request; please contact Momento.",
+            transportDetails);
+}
+
+/// Insufficient permissions to perform operation
+class PermissionException extends SdkException {
+  PermissionException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.permissionError,
+            innerException,
+            "Insufficient permissions to perform an operation.",
+            transportDetails);
+}
+
+/// Invalid authentication credentials to connect to service
+class AuthenticationException extends SdkException {
+  AuthenticationException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.authenticationError,
+            innerException,
+            "Invalid authentication credentials to connect to service.",
+            transportDetails);
+}
+
+/// Request was cancelled by the server
+class CancelledException extends SdkException {
+  CancelledException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.cancelledError,
+            innerException,
+            "The request was cancelled by the server; please contact Momento.",
+            transportDetails);
+}
+
+/// Request rate, bandwidth, or object size exceeded the limits for the account
+class LimitExceededException extends SdkException {
+  LimitExceededException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.limitExceededError,
+            innerException,
+            "Request rate, bandwidth, or object size exceeded the limits for this account.  To resolve this error, reduce your usage as appropriate or contact Momento to request a limit increase.",
+            transportDetails);
+}
+
+/// Request was invalid
+class BadRequestException extends SdkException {
+  BadRequestException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.badRequestError,
+            innerException,
+            "The request was invalid; please contact Momento.",
+            transportDetails);
+}
+
+/// Client's configured timeout was exceeded
+class TimeoutException extends SdkException {
+  TimeoutException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.timeoutError,
+            innerException,
+            "The client's configured timeout was exceeded; you may need to use a configuration with more lenient timeouts.",
+            transportDetails);
+}
+
+/// Server was unable to handle the request
+class ServerUnavailableException extends SdkException {
+  ServerUnavailableException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.serverUnavailable,
+            innerException,
+            "The server was unable to handle the request; consider retrying.  If the error persists, please contact Momento.",
+            transportDetails);
+}
+
+/// A client resource (most likely memory) was exhausted
+class ClientResourceExhaustedException extends SdkException {
+  ClientResourceExhaustedException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.clientResourceExhausted,
+            innerException,
+            "A client resource (most likely memory) was exhausted.  If you are executing a high volume of concurrent requests or using very large object sizes, your Configuration may need to be updated to allocate more memory.  Please contact Momento for assistance.",
+            transportDetails);
+}
+
+/// System is not in a state required for the operation's execution
+class FailedPreconditionException extends SdkException {
+  FailedPreconditionException(String message, Exception? innerException,
+      MomentoErrorTransportDetails? transportDetails)
+      : super(
+            message,
+            MomentoErrorCode.failedPreconditionError,
+            innerException,
+            "System is not in a state required for the operation's execution; please contact Momento.",
+            transportDetails);
 }

lib/src/internal/pubsub_client.dart

@@ -32,7 +32,8 @@ class ClientPubsub implements AbstractPubsubClient {
       if (e is SdkException) {
         return TopicPublishError(e);
       }
-      return TopicPublishError(UnknownException("Unexpected error: $e", null));
+      return TopicPublishError(
+          UnknownException("Unexpected error: $e", null, null));
     }
   }
 

lib/src/messages/responses/responses_base.dart

@@ -2,5 +2,5 @@ import '../../errors/errors.dart';
 
 class ErrorResponseBase extends AbstractExceptionResponseBase {
   ErrorResponseBase(SdkException exception)
-      : super(exception.message, exception.innerException);
+      : super(exception.message, exception.errorCode, exception.innerException);
 }

lib/src/messages/values.dart

@@ -1,7 +1,7 @@
 sealed class Value {}
 
 class StringValue implements Value {
-  final String _value;
+  String _value;
   StringValue(String v) : _value = v;
   String get value => _value;
 }