Allow lowering input validation severity on examples

docs/source-2.0/spec/documentation-traits.rst

@@ -139,11 +139,22 @@ Each ``example`` trait value is a structure with the following members:
       - :ref:`examples-ErrorExample-structure`
       - Provides an error shape ID and example error parameters for the
         operation.
-
-The values provided for the ``input`` and ``output`` members MUST be
-compatible with the shapes and constraints of the corresponding structure.
-These values use the same semantics and format as
-:ref:`custom trait values <trait-node-values>`.
+    * - lowerInputValidationSeverity
+      - ``[string]``
+      - Lowers input validation events from ERROR to WARNING for specific
+        validation types. List can include: ``BLOB_LENGTH_WARNING``,
+        ``MAP_LENGTH_WARNING``, ``PATTERN_TRAIT_WARNING``,
+        ``RANGE_TRAIT_WARNING``, ``REQUIRED_TRAIT_WARNING``,
+        ``STRING_LENGTH_WARNING``.
+
+
+When ``input`` and ``output`` members are present, both MUST be compatible
+with the shapes and constraints of the corresponding structure. When ``input``
+and ``error`` members are present, input validation events will be emitted as
+an ``ERROR`` by default. Specific validation events for the ``input`` can be
+lowered to a ``WARNING`` by setting the appropriate
+``lowerInputValidationSeverity`` value. ``input`` and ``output`` members use
+the same semantics and format as :ref:`custom trait values <trait-node-values>`.
 
 A value for ``output`` or ``error`` SHOULD be provided. However, both
 MUST NOT be defined for the same example.
@@ -186,7 +197,8 @@ MUST NOT be defined for the same example.
                 content: {
                     message: "Invalid 'foo'. Special character not allowed."
                 }
-            }
+            },
+            lowerInputValidationSeverity: ["PATTERN_TRAIT_WARNING"]
         }
     ])
 

smithy-model/src/main/java/software/amazon/smithy/model/traits/ExamplesTrait.java

@@ -19,12 +19,15 @@
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.stream.Collectors;
 import software.amazon.smithy.model.node.ArrayNode;
 import software.amazon.smithy.model.node.Node;
 import software.amazon.smithy.model.node.ObjectNode;
 import software.amazon.smithy.model.node.ToNode;
 import software.amazon.smithy.model.shapes.ShapeId;
+import software.amazon.smithy.model.validation.NodeValidationVisitor;
 import software.amazon.smithy.model.validation.validators.ExamplesTraitValidator;
+import software.amazon.smithy.utils.BuilderRef;
 import software.amazon.smithy.utils.SmithyBuilder;
 import software.amazon.smithy.utils.ToSmithyBuilder;
 
@@ -55,6 +58,24 @@ protected Node createNode() {
         return examples.stream().map(Example::toNode).collect(ArrayNode.collect(getSourceLocation()));
     }
 
+    @Override
+    public boolean equals(Object other) {
+        if (!(other instanceof ExamplesTrait)) {
+            return false;
+        } else if (other == this) {
+            return true;
+        } else {
+            ExamplesTrait trait = (ExamplesTrait) other;
+            return this.examples.size() == trait.examples.size() && this.examples.containsAll(trait.examples);
+        }
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(toShapeId(), examples);
+    }
+
+
     @Override
     public Builder toBuilder() {
         Builder builder = new Builder().sourceLocation(getSourceLocation());
@@ -70,7 +91,7 @@ public static Builder builder() {
     }
 
     /**
-     * Builds and examples trait.
+     * Builds an examples trait.
      */
     public static final class Builder extends AbstractTraitBuilder<ExamplesTrait, Builder> {
         private final List<Example> examples = new ArrayList<>();
@@ -100,13 +121,15 @@ public static final class Example implements ToNode, ToSmithyBuilder<Example> {
         private final ObjectNode input;
         private final ObjectNode output;
         private final ErrorExample error;
+        private final List<NodeValidationVisitor.Feature> lowerInputValidationSeverity;
 
         private Example(Builder builder) {
             this.title = Objects.requireNonNull(builder.title, "Example title must not be null");
             this.documentation = builder.documentation;
             this.input = builder.input;
             this.output = builder.output;
             this.error = builder.error;
+            this.lowerInputValidationSeverity = builder.lowerInputValidationSeverity.get();
         }
 
         /**
@@ -144,6 +167,13 @@ public Optional<ErrorExample> getError() {
             return Optional.ofNullable(error);
         }
 
+        /**
+         * @return Gets the list of lowered input validation severities.
+         */
+        public Optional<List<NodeValidationVisitor.Feature>> getLowerInputValidationSeverity() {
+            return Optional.ofNullable(lowerInputValidationSeverity);
+        }
+
         @Override
         public Node toNode() {
             ObjectNode.Builder builder = Node.objectNodeBuilder()
@@ -157,13 +187,20 @@ public Node toNode() {
             if (this.getOutput().isPresent()) {
                 builder.withMember("output", output);
             }
+            if (this.getLowerInputValidationSeverity().isPresent()) {
+                builder.withMember("lowerInputValidationSeverity", ArrayNode.fromNodes(lowerInputValidationSeverity
+                        .stream()
+                        .map(NodeValidationVisitor.Feature::toNode)
+                        .collect(Collectors.toList())));
+            }
 
             return builder.build();
         }
 
         @Override
         public Builder toBuilder() {
-            return new Builder().documentation(documentation).title(title).input(input).output(output).error(error);
+            return new Builder().documentation(documentation).title(title).input(input).output(output).error(error)
+                    .lowerInputValidationSeverity(lowerInputValidationSeverity);
         }
 
         public static Builder builder() {
@@ -179,6 +216,7 @@ public static final class Builder implements SmithyBuilder<Example> {
             private ObjectNode input = Node.objectNode();
             private ObjectNode output;
             private ErrorExample error;
+            private BuilderRef<List<NodeValidationVisitor.Feature>> lowerInputValidationSeverity = BuilderRef.forList();
 
             @Override
             public Example build() {
@@ -209,6 +247,14 @@ public Builder error(ErrorExample error) {
                 this.error = error;
                 return this;
             }
+
+            public Builder lowerInputValidationSeverity(
+                    List<NodeValidationVisitor.Feature> lowerInputValidationSeverity
+            ) {
+                this.lowerInputValidationSeverity.clear();
+                this.lowerInputValidationSeverity.get().addAll(lowerInputValidationSeverity);
+                return this;
+            }
         }
     }
 
@@ -302,7 +348,9 @@ private static Example exampleFromNode(ObjectNode node) {
                     .getStringMember("documentation", builder::documentation)
                     .getObjectMember("input", builder::input)
                     .getObjectMember("output", builder::output)
-                    .getMember("error", ErrorExample::fromNode, builder::error);
+                    .getMember("error", ErrorExample::fromNode, builder::error)
+                    .getArrayMember("lowerInputValidationSeverity", NodeValidationVisitor.Feature::fromNode,
+                                    builder::lowerInputValidationSeverity);
             return builder.build();
         }
     }

smithy-model/src/main/java/software/amazon/smithy/model/validation/NodeValidationVisitor.java

@@ -104,10 +104,36 @@ public enum Feature {
          * Emit a warning when a range trait is incompatible with a default value of 0.
          *
          * <p>This was a common pattern in Smithy 1.0 and earlier. It implies that the value is effectively
-         * required. However, chaning the type of the value by un-boxing it or adjusting the range trait would
-         * be a lossy tranformation when migrating a model from 1.0 to 2.0.
+         * required. However, changing the type of the value by un-boxing it or adjusting the range trait would
+         * be a lossy transformation when migrating a model from 1.0 to 2.0.
          */
-        RANGE_TRAIT_ZERO_VALUE_WARNING
+        RANGE_TRAIT_ZERO_VALUE_WARNING,
+
+        // Lowers severity of Length Trait validations on blobs to a WARNING.
+        BLOB_LENGTH_WARNING,
+
+        // Lowers severity of Length Trait validations on maps to a WARNING.
+        MAP_LENGTH_WARNING,
+
+        // Lowers severity of Pattern Trait validations to a WARNING.
+        PATTERN_TRAIT_WARNING,
+
+        // Lowers severity of Range Trait validations to a WARNING.
+        RANGE_TRAIT_WARNING,
+
+        // Lowers severity of Required Trait validations to a WARNING.
+        REQUIRED_TRAIT_WARNING,
+
+        // Lowers severity of Length Trait validations on strings to a WARNING.
+        STRING_LENGTH_WARNING,;
+
+        public static Feature fromNode(Node node) {
+            return Feature.valueOf(node.expectStringNode().getValue());
+        }
+
+        public static Node toNode(Feature feature) {
+            return StringNode.from(feature.toString());
+        }
     }
 
     public static Builder builder() {
@@ -317,9 +343,11 @@ public List<ValidationEvent> structureShape(StructureShape shape) {
 
                     for (MemberShape member : members.values()) {
                         if (member.isRequired() && !object.getMember(member.getMemberName()).isPresent()) {
+                            Severity severity = this.validationContext.hasFeature(Feature.REQUIRED_TRAIT_WARNING)
+                                    ? Severity.WARNING : Severity.ERROR;
                             events.add(event(String.format(
                                     "Missing required structure member `%s` for `%s`",
-                                    member.getMemberName(), shape.getId())));
+                                    member.getMemberName(), shape.getId()), severity));
                         }
                     }
                     return events;

smithy-model/src/main/java/software/amazon/smithy/model/validation/node/BlobLengthPlugin.java

@@ -20,6 +20,8 @@
 import software.amazon.smithy.model.shapes.BlobShape;
 import software.amazon.smithy.model.shapes.Shape;
 import software.amazon.smithy.model.traits.LengthTrait;
+import software.amazon.smithy.model.validation.NodeValidationVisitor;
+import software.amazon.smithy.model.validation.Severity;
 import software.amazon.smithy.utils.SmithyInternalApi;
 
 /**
@@ -39,16 +41,23 @@ protected void check(Shape shape, LengthTrait trait, StringNode node, Context co
 
         trait.getMin().ifPresent(min -> {
             if (size < min) {
-                emitter.accept(node, "Value provided for `" + shape.getId() + "` must have at least "
-                                     + min + " bytes, but the provided value only has " + size + " bytes");
+                emitter.accept(node, getSeverity(context), "Value provided for `" + shape.getId()
+                            + "` must have at least " + min + " bytes, but the provided value only has " + size
+                            + " bytes");
             }
         });
 
         trait.getMax().ifPresent(max -> {
             if (value.getBytes(StandardCharsets.UTF_8).length > max) {
-                emitter.accept(node, "Value provided for `" + shape.getId() + "` must have no more than "
-                                     + max + " bytes, but the provided value has " + size + " bytes");
+                emitter.accept(node, getSeverity(context), "Value provided for `" + shape.getId()
+                            + "` must have no more than " + max + " bytes, but the provided value has " + size
+                            + " bytes");
             }
         });
     }
+
+    private Severity getSeverity(Context context) {
+        return context.hasFeature(NodeValidationVisitor.Feature.BLOB_LENGTH_WARNING)
+                ? Severity.WARNING : Severity.ERROR;
+    }
 }

smithy-model/src/main/java/software/amazon/smithy/model/validation/node/MapLengthPlugin.java

@@ -19,6 +19,8 @@
 import software.amazon.smithy.model.shapes.MapShape;
 import software.amazon.smithy.model.shapes.Shape;
 import software.amazon.smithy.model.traits.LengthTrait;
+import software.amazon.smithy.model.validation.NodeValidationVisitor;
+import software.amazon.smithy.model.validation.Severity;
 import software.amazon.smithy.utils.SmithyInternalApi;
 
 /**
@@ -35,18 +37,23 @@ final class MapLengthPlugin extends MemberAndShapeTraitPlugin<MapShape, ObjectNo
     protected void check(Shape shape, LengthTrait trait, ObjectNode node, Context context, Emitter emitter) {
         trait.getMin().ifPresent(min -> {
             if (node.size() < min) {
-                emitter.accept(node, String.format(
+                emitter.accept(node, getSeverity(context), String.format(
                         "Value provided for `%s` must have at least %d entries, but the provided value only "
                         + "has %d entries", shape.getId(), min, node.size()));
             }
         });
 
         trait.getMax().ifPresent(max -> {
             if (node.size() > max) {
-                emitter.accept(node, String.format(
+                emitter.accept(node, getSeverity(context), String.format(
                         "Value provided for `%s` must have no more than %d entries, but the provided value "
                         + "has %d entries", shape.getId(), max, node.size()));
             }
         });
     }
+
+    private Severity getSeverity(Context context) {
+        return context.hasFeature(NodeValidationVisitor.Feature.MAP_LENGTH_WARNING)
+                ? Severity.WARNING : Severity.ERROR;
+    }
 }

smithy-model/src/main/java/software/amazon/smithy/model/validation/node/PatternTraitPlugin.java

@@ -19,6 +19,8 @@
 import software.amazon.smithy.model.shapes.Shape;
 import software.amazon.smithy.model.shapes.StringShape;
 import software.amazon.smithy.model.traits.PatternTrait;
+import software.amazon.smithy.model.validation.NodeValidationVisitor;
+import software.amazon.smithy.model.validation.Severity;
 
 /**
  * Validates the pattern trait on string shapes or members that target them.
@@ -32,9 +34,15 @@ final class PatternTraitPlugin extends MemberAndShapeTraitPlugin<StringShape, St
     @Override
     protected void check(Shape shape, PatternTrait trait, StringNode node, Context context, Emitter emitter) {
         if (!trait.getPattern().matcher(node.getValue()).find()) {
-            emitter.accept(node, String.format(
+            emitter.accept(node, getSeverity(context), String.format(
                     "String value provided for `%s` must match regular expression: %s",
                     shape.getId(), trait.getPattern().pattern()));
         }
     }
+
+
+    private Severity getSeverity(Context context) {
+        return context.hasFeature(NodeValidationVisitor.Feature.PATTERN_TRAIT_WARNING)
+                ? Severity.WARNING : Severity.ERROR;
+    }
 }