Merge pull request #107 from eclipse-thingweb/exception-simplification

feat!: simplify custom exceptions

Author: JKRhb

lib/core.dart

@@ -10,5 +10,6 @@
 library core;
 
 export "src/core/definitions.dart";
+export "src/core/exceptions.dart";
 export "src/core/implementation.dart";
 export "src/core/scripting_api.dart";

lib/src/core/definitions.dart

@@ -44,6 +44,4 @@ export "definitions/security/psk_security_scheme.dart";
 export "definitions/security/security_scheme.dart";
 export "definitions/thing_description.dart";
 export "definitions/thing_model.dart";
-export "definitions/validation/thing_description_schema.dart"
-    show ThingDescriptionValidationException, thingDescriptionSchema;
-export "definitions/validation/validation_exception.dart";
+export "definitions/validation/thing_description_schema.dart";

lib/src/core/definitions/extensions/json_parser.dart

@@ -7,6 +7,7 @@
 import "package:collection/collection.dart";
 import "package:curie/curie.dart";
 
+import "../../exceptions.dart";
 import "../additional_expected_response.dart";
 import "../data_schema.dart";
 import "../expected_response.dart";
@@ -26,7 +27,6 @@ import "../security/oauth2_security_scheme.dart";
 import "../security/psk_security_scheme.dart";
 import "../security/security_scheme.dart";
 import "../thing_description.dart";
-import "../validation/validation_exception.dart";
 import "../version_info.dart";
 
 const _validTdContextValues = [
@@ -638,7 +638,9 @@ List<ContextEntry> _parseContext(
           final value = entry.value;
 
           if (value is! String) {
-            throw ContextValidationException(value.runtimeType);
+            throw ValidationException(
+                "Excepted either a String or a Map<String, String> "
+                "as @context entry, got ${value.runtimeType} instead.");
           }
 
           if (!key.startsWith("@") && Uri.tryParse(value) != null) {
@@ -649,16 +651,6 @@ List<ContextEntry> _parseContext(
       }
   }
 
-  throw ContextValidationException(json.runtimeType);
-}
-
-/// Custom [ValidationException] that is thrown for an invalid [ContextEntry].
-class ContextValidationException extends ValidationException {
-  /// Creates a new [ContextValidationException] indicating the invalid
-  /// [runtimeType].
-  ContextValidationException(Type runtimeType)
-      : super(
-          "Excepted either a String or a Map<String, String> "
-          "as @context entry, got $runtimeType instead.",
-        );
+  throw ValidationException("Excepted either a String or a Map<String, String> "
+      "as @context entry, got ${json.runtimeType} instead.");
 }

lib/src/core/definitions/operation_type.dart

@@ -4,8 +4,8 @@
 //
 // SPDX-License-Identifier: BSD-3-Clause
 
+import "../exceptions.dart";
 import "interaction_affordances/interaction_affordance.dart";
-import "validation/validation_exception.dart";
 
 /// Enumeration for the possible WoT operation types.
 ///

lib/src/core/definitions/thing_description.dart

@@ -7,6 +7,7 @@
 import "package:curie/curie.dart";
 import "package:meta/meta.dart";
 
+import "../exceptions.dart";
 import "additional_expected_response.dart";
 import "data_schema.dart";
 import "extensions/json_parser.dart";
@@ -61,8 +62,8 @@ class ThingDescription {
     if (validate) {
       final validationResult = thingDescriptionSchema.validate(json);
       if (!validationResult.isValid) {
-        throw ThingDescriptionValidationException(
-          json,
+        throw ValidationException(
+          "Validation of Thing Description failed.",
           validationResult.errors,
         );
       }

lib/src/core/definitions/validation/thing_description_schema.dart

@@ -6,32 +6,9 @@
 
 import "package:json_schema/json_schema.dart";
 
-import "validation_exception.dart";
-
 /// JSON Schema definition used for validating Thing Descriptions.
 final thingDescriptionSchema = JsonSchema.create(_rawThingDescriptionSchema);
 
-/// [Exception] that is thrown when a Thing Description is identified as being
-/// invalid.
-class ThingDescriptionValidationException extends ValidationException {
-  /// Constructor.
-  ThingDescriptionValidationException(
-    this.rawThingDescription,
-    this._validationErrors,
-  ) : super("Validation of Thing Description failed");
-
-  final List<ValidationError> _validationErrors;
-
-  /// The raw Thing Description that is invalid.
-  Map<String, dynamic> rawThingDescription;
-
-  @override
-  String toString() {
-    return "ThingDescriptionValidationException: $message.\n\n"
-        'Errors:\n\n ${_validationErrors.join("\n")}';
-  }
-}
-
 final Map<String, dynamic> _rawThingDescriptionSchema = <String, dynamic>{
   "title": "Thing Description",
   "version": "1.1-09-November-2023",

lib/src/core/definitions/validation/validation_exception.dart

@@ -0,0 +1,57 @@
+// Copyright 2024 Contributors to the Eclipse Foundation. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+/// Base class for custom exceptions defined in `dart_wot`.
+base class DartWotException implements Exception {
+  /// Constructor.
+  DartWotException(this.message);
+
+  /// The error message of this [ValidationException].
+  final String message;
+
+  /// The name of this [Exception] that will appear in the error message log.
+  final exceptionType = "DartWotException";
+
+  @override
+  String toString() => "$exceptionType: $message";
+}
+
+/// An [Exception] that is thrown when the validation of a definition fails.
+base class ValidationException extends DartWotException {
+  /// Constructor.
+  ValidationException(super.message, [this._validationErrors]);
+
+  final List<Object>? _validationErrors;
+
+  @override
+  String get exceptionType => "ValidationException";
+
+  @override
+  String toString() {
+    final String formattedValidationErrors;
+
+    final validationErrors = _validationErrors;
+    if (validationErrors != null) {
+      formattedValidationErrors = [
+        "\n\nErrors:\n",
+        ...validationErrors,
+      ].join("\n");
+    } else {
+      formattedValidationErrors = "";
+    }
+
+    return "$exceptionType: $message$formattedValidationErrors";
+  }
+}
+
+/// Custom [Exception] that is thrown when the discovery process fails.
+final class DiscoveryException extends DartWotException {
+  /// Creates a new [DiscoveryException] with the specified error [message].
+  DiscoveryException(super.message);
+
+  @override
+  String get exceptionType => "DiscoveryException";
+}

lib/src/core/exceptions.dart

@@ -11,7 +11,6 @@ export "implementation/augmented_form.dart";
 export "implementation/codecs/content_codec.dart";
 export "implementation/content.dart";
 export "implementation/content_serdes.dart";
-export "implementation/discovery_exception.dart";
 export "implementation/protocol_interfaces/protocol_client.dart";
 export "implementation/protocol_interfaces/protocol_client_factory.dart";
 export "implementation/protocol_interfaces/protocol_server.dart";

lib/src/core/implementation.dart

@@ -10,6 +10,7 @@ import "package:meta/meta.dart";
 import "package:uri/uri.dart";
 
 import "../definitions.dart";
+import "../exceptions.dart";
 
 /// A [Form] augmented with information from its asscociated [_thingDescription]
 /// and [_interactionAffordance].
@@ -166,20 +167,3 @@ final class AugmentedForm implements Form {
     }
   }
 }
-
-/// This [Exception] is thrown when [URI variables] are being used in the [Form]
-/// of a TD but no (valid) values were provided.
-///
-/// [URI variables]: https://www.w3.org/TR/wot-thing-description11/#form-uriVariables
-class UriVariableException implements Exception {
-  /// Constructor.
-  UriVariableException(this.message);
-
-  /// The error [message].
-  final String message;
-
-  @override
-  String toString() {
-    return "UriVariableException: $message";
-  }
-}