Adds support for validating idn-hostname and idn-email (#775)

Resolves #774

Co-authored-by: Faron Dutton <[email protected]>

Author: fdutton

src/main/java/com/networknt/schema/JsonMetaSchema.java

@@ -19,6 +19,8 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import com.networknt.schema.format.DateFormat;
 import com.networknt.schema.format.EmailFormat;
+import com.networknt.schema.format.IdnEmailFormat;
+import com.networknt.schema.format.IdnHostnameFormat;
 import com.networknt.schema.format.IriFormat;
 import com.networknt.schema.format.IriReferenceFormat;
 import com.networknt.schema.format.PatternFormat;
@@ -59,6 +61,8 @@ static PatternFormat pattern(String name, String regex) {
         COMMON_BUILTIN_FORMATS.add(pattern("uuid", "^\\p{XDigit}{8}-\\p{XDigit}{4}-\\p{XDigit}{4}-\\p{XDigit}{4}-\\p{XDigit}{12}$", "must be a valid RFC 4122 UUID"));
         COMMON_BUILTIN_FORMATS.add(new DateFormat());
         COMMON_BUILTIN_FORMATS.add(new EmailFormat());
+        COMMON_BUILTIN_FORMATS.add(new IdnEmailFormat());
+        COMMON_BUILTIN_FORMATS.add(new IdnHostnameFormat());
         COMMON_BUILTIN_FORMATS.add(new IriFormat());
         COMMON_BUILTIN_FORMATS.add(new IriReferenceFormat());
         COMMON_BUILTIN_FORMATS.add(new RegexFormat());

src/main/java/com/networknt/schema/format/EmailFormat.java

@@ -24,25 +24,11 @@ public class EmailFormat extends AbstractFormat {
 
     public EmailFormat() {
         super("email", "must be a valid RFC 5321 Mailbox");
-        this.emailValidator = new SpecialEmailValidator(true, true);
+        this.emailValidator = new IPv6AwareEmailValidator(true, true);
     }
 
     @Override
     public boolean matches(String value) {
         return this.emailValidator.isValid(value);
     }
-
-    static class SpecialEmailValidator extends EmailValidator {
-        private static final long serialVersionUID = 1L;
-
-        public SpecialEmailValidator(boolean b, boolean c) {
-            super(b, c);
-        }
-
-        @Override
-        protected boolean isValidDomain(String domain) {
-            return super.isValidDomain(domain.startsWith("[IPv6:") ? domain.replace("IPv6:", "") : domain);
-        }
-
-    }
 }

src/main/java/com/networknt/schema/format/IPv6AwareEmailValidator.java

@@ -0,0 +1,33 @@
+package com.networknt.schema.format;
+
+import com.networknt.org.apache.commons.validator.routines.DomainValidator;
+import com.networknt.org.apache.commons.validator.routines.EmailValidator;
+
+/**
+ * This is an extension of the Apache Commons Validator that correctly
+ * handles email addresses containing an IPv6 literal as the domain.
+ * <p>
+ * Apache's {@link EmailValidator} delegates validation of the domain to
+ * its {@link DomainValidator}, which is not aware that it is validating
+ * an email address, which has a peculiar way of representing an IPv6
+ * literal.
+ */
+class IPv6AwareEmailValidator extends EmailValidator {
+    private static final long serialVersionUID = 1L;
+
+    /**
+     * Creates a new IPv6AwareEmailValidator.
+     *
+     * @param allowLocal Should local addresses be considered valid?
+     * @param allowTld Should TLDs be allowed?
+     */
+    public IPv6AwareEmailValidator(final boolean allowLocal, final boolean allowTld) {
+        super(allowLocal, allowTld);
+    }
+
+    @Override
+    protected boolean isValidDomain(String domain) {
+        return super.isValidDomain(domain.startsWith("[IPv6:") ? domain.replace("IPv6:", "") : domain);
+    }
+
+}

src/main/java/com/networknt/schema/format/IdnEmailFormat.java

@@ -0,0 +1,19 @@
+package com.networknt.schema.format;
+
+import com.networknt.org.apache.commons.validator.routines.EmailValidator;
+
+public class IdnEmailFormat extends AbstractFormat {
+
+    private final EmailValidator emailValidator;
+
+    public IdnEmailFormat() {
+        super("idn-email", "must be a valid RFC 6531 Mailbox");
+        this.emailValidator = new IPv6AwareEmailValidator(true, true);
+    }
+
+    @Override
+    public boolean matches(String value) {
+        return this.emailValidator.isValid(value);
+    }
+
+}

src/main/java/com/networknt/schema/format/IdnHostnameFormat.java

@@ -0,0 +1,16 @@
+package com.networknt.schema.format;
+
+import com.networknt.schema.utils.RFC5892;
+
+public class IdnHostnameFormat extends AbstractFormat {
+
+    public IdnHostnameFormat() {
+        super("idn-hostname", "must be a valid RFC 5890 internationalized hostname");
+    }
+
+    @Override
+    public boolean matches(String value) {
+        if (null == value || value.isEmpty()) return true;
+        return RFC5892.isValid(value);
+    }
+}