sha256 support

Author: cliffcaseyyet

src/main/java/com/yetanalytics/xapi/model/Attachment.java

@@ -9,6 +9,7 @@
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
 import com.yetanalytics.xapi.model.deserializers.MimeTypeDeserializer;
+import com.yetanalytics.xapi.validation.Sha256Sum;
 
 import jakarta.activation.MimeType;
 
@@ -35,8 +36,8 @@ public class Attachment implements JSONObject {
     @NotNull
     private Integer length;
 
-    // TODO: Validate that sha2 is a SHA256, 64-char hex string
     @NotNull
+    @Sha256Sum
     private String sha2;
 
     private URI fileUrl;

src/main/java/com/yetanalytics/xapi/util/HashUtils.java

@@ -4,10 +4,15 @@
 
 public final class HashUtils {
     private static final Pattern SHA1_HEX_PATTERN = Pattern.compile("^[0-9a-fA-F]{40}$");
+    private static final Pattern SHA256_HEX_PATTERN = Pattern.compile("^[0-9a-fA-F]{64}$");
 
     private HashUtils() {}
 
     public static boolean isSha1Hex(String value) {
         return value != null && SHA1_HEX_PATTERN.matcher(value).matches();
     }
+
+    public static boolean isSha256Hex(String value) {
+        return value != null && SHA256_HEX_PATTERN.matcher(value).matches();
+    }
 }

src/main/java/com/yetanalytics/xapi/validation/Sha256Sum.java

@@ -0,0 +1,22 @@
+package com.yetanalytics.xapi.validation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import jakarta.validation.Constraint;
+import jakarta.validation.Payload;
+
+@Documented
+@Constraint(validatedBy = Sha256SumValidator.class)
+@Target({ ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER, ElementType.TYPE_USE })
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Sha256Sum {
+    String message() default "must be a 64-character SHA-256 hex string";
+
+    Class<?>[] groups() default {};
+
+    Class<? extends Payload>[] payload() default {};
+}

src/main/java/com/yetanalytics/xapi/validation/Sha256SumValidator.java

@@ -0,0 +1,14 @@
+package com.yetanalytics.xapi.validation;
+
+import com.yetanalytics.xapi.util.HashUtils;
+
+import jakarta.validation.ConstraintValidator;
+import jakarta.validation.ConstraintValidatorContext;
+
+public class Sha256SumValidator implements ConstraintValidator<Sha256Sum, String> {
+
+    @Override
+    public boolean isValid(String value, ConstraintValidatorContext context) {
+        return value == null || HashUtils.isSha256Hex(value);
+    }
+}

src/test/java/com/yetanalytics/model/AttachmentTest.java

@@ -25,8 +25,7 @@ public void init() {
         attachment = new Attachment();
     }
 
-    @Test
-    public void testAttachment() throws URISyntaxException, MimeTypeParseException {
+    private void populateValidAttachment() throws URISyntaxException, MimeTypeParseException {
         LangMap display = new LangMap(new HashMap<>());
         display.put("en-US", "Display");
 
@@ -45,10 +44,28 @@ public void testAttachment() throws URISyntaxException, MimeTypeParseException {
         attachment.setLength(length);
         attachment.setSha2(sha2);
         attachment.setFileUrl(fileUrl);
+    }
 
+    @Test
+    public void testAttachment() throws URISyntaxException, MimeTypeParseException {
+        populateValidAttachment();
         ValidationUtils.assertValid(validator, attachment);
     }
 
+    @Test
+    public void testInvalidSha2Length() throws URISyntaxException, MimeTypeParseException {
+        populateValidAttachment();
+        attachment.setSha2("426cf3a8b2864dd91201b989ba5728181da52bfff9a0489670e54cd8ec8b3a5");
+        ValidationUtils.assertInvalid(validator, attachment);
+    }
+
+    @Test
+    public void testInvalidSha2Hex() throws URISyntaxException, MimeTypeParseException {
+        populateValidAttachment();
+        attachment.setSha2("z26cf3a8b2864dd91201b989ba5728181da52bfff9a0489670e54cd8ec8b3a50");
+        ValidationUtils.assertInvalid(validator, attachment);
+    }
+
     @Test
     public void testEmptyAttachment() {
         // One error for empty attachment, one error each for null properties