chore: add AvroValidationRule for names and symbols (#197)

src/LEGO.AsyncAPI/Resource.resx

@@ -132,4 +132,10 @@
   <data name="Validation_MustBeAbsoluteUrl" xml:space="preserve">
     <value>The field '{0}' in '{1}' object MUST be an absolute uri.</value>
   </data>
+  <data name="Validation_NameMustMatchRegularExpr" xml:space="preserve">
+    <value>'{0}'  MUST match the regular expression '{1}'.</value>
+  </data>
+  <data name="Validation_SymbolsMustMatchRegularExpression" xml:space="preserve">
+    <value>Symbols  MUST match the regular expression '{1}'.</value>
+  </data>
 </root>

src/LEGO.AsyncAPI/Services/AsyncApiVisitorBase.cs

@@ -55,6 +55,14 @@ public virtual void Visit(AsyncApiDocument doc)
         {
         }
 
+        public virtual void Visit(AsyncApiJsonSchemaPayload jsonPayload)
+        {
+        }
+
+        public virtual void Visit(AsyncApiAvroSchemaPayload avroPayload)
+        {
+        }
+
         public virtual void Visit(IDictionary<string, AsyncApiAny> anys)
         {
         }

src/LEGO.AsyncAPI/Services/AsyncApiWalker.cs

@@ -326,6 +326,11 @@ internal void Walk(AsyncApiParameter parameter, bool isComponent = false)
             this.Walk(parameter as IAsyncApiExtensible);
         }
 
+        internal void Walk(AsyncApiAvroSchemaPayload payload)
+        {
+            this.visitor.Visit(payload);
+        }
+
         internal void Walk(AsyncApiSchema schema, bool isComponent = false)
         {
             if (schema == null || this.ProcessAsReference(schema, isComponent))
@@ -539,7 +544,11 @@ internal void Walk(AsyncApiMessage message, bool isComponent = false)
                     this.Walk(AsyncApiConstants.Payload, () => this.Walk((AsyncApiSchema)payload));
                 }
 
-                // #ToFix Add walking for avro.
+                if (message.Payload is AsyncApiAvroSchemaPayload avroPayload)
+                {
+                    this.Walk(AsyncApiConstants.Payload, () => this.Walk(avroPayload));
+                }
+
                 this.Walk(AsyncApiConstants.CorrelationId, () => this.Walk(message.CorrelationId));
                 this.Walk(AsyncApiConstants.Tags, () => this.Walk(message.Tags));
                 this.Walk(AsyncApiConstants.Examples, () => this.Walk(message.Examples));

src/LEGO.AsyncAPI/Validation/AsyncApiValidator.cs

@@ -144,6 +144,10 @@ public void AddWarning(AsyncApiValidatorWarning warning)
 
         public override void Visit(IMessageBinding item) => this.Validate(item);
 
+        public override void Visit(AsyncApiAvroSchemaPayload item) => this.Validate(item);
+
+        public override void Visit(AsyncApiJsonSchemaPayload item) => this.Validate(item);
+
         /// <summary>
         /// Execute validation rules against an <see cref="IAsyncApiExtensible"/>.
         /// </summary>

src/LEGO.AsyncAPI/Validation/Rules/AsyncApiAvroRules.cs

@@ -0,0 +1,60 @@
+// Copyright (c) The LEGO Group. All rights reserved.
+
+namespace LEGO.AsyncAPI.Validation.Rules
+{
+    using System.Linq;
+    using System.Text.RegularExpressions;
+    using LEGO.AsyncAPI.Models;
+    using LEGO.AsyncAPI.Validations;
+
+    [AsyncApiRule]
+    public static class AsyncApiAvroRules
+    {
+        /// <summary>
+        /// The key regex.
+        /// </summary>
+        public static Regex NameRegex = new Regex(@"^[A-Za-z_][A-Za-z0-9_]*$");
+
+        public static ValidationRule<AsyncApiAvroSchemaPayload> NameRegularExpression =>
+            new ValidationRule<AsyncApiAvroSchemaPayload>(
+                (context, avroPayload) =>
+                {
+                    string name = null;
+                    context.Enter("name");
+                    if (avroPayload.TryGetAs<AvroRecord>(out var record))
+                    {
+                        name = record.Name;
+                    }
+
+                    if (avroPayload.TryGetAs<AvroEnum>(out var @enum))
+                    {
+                        name = @enum.Name;
+                        if (@enum.Symbols.Any(symbol => !NameRegex.IsMatch(symbol)))
+                        {
+                            context.CreateError(
+                                "SymbolsRegularExpression",
+                                string.Format(Resource.Validation_SymbolsMustMatchRegularExpression, NameRegex.ToString()));
+                        }
+                    }
+
+                    if (avroPayload.TryGetAs<AvroFixed>(out var @fixed))
+                    {
+                        name = @fixed.Name;
+                    }
+
+                    if (name == null)
+                    {
+                        return;
+                    }
+
+                    if (!NameRegex.IsMatch(record.Name))
+                    {
+                        context.CreateError(
+                            nameof(NameRegex),
+                            string.Format(Resource.Validation_NameMustMatchRegularExpr, name, NameRegex.ToString()));
+                    }
+
+                    context.Exit();
+                });
+    }
+}

test/LEGO.AsyncAPI.Tests/Validation/ValidationRulesetTests.cs

@@ -35,7 +35,7 @@ public void DefaultRuleSet_PropertyReturnsTheCorrectRules()
             Assert.IsNotEmpty(rules);
 
             // Update the number if you add new default rule(s).
-            Assert.AreEqual(17, rules.Count);
+            Assert.AreEqual(18, rules.Count);
         }
     }
 }