fix: Add NoAuthentication

src/main/java/org/hisp/dhis/BaseDhis2.java

@@ -167,6 +167,11 @@ public class BaseDhis2 {
 
   protected final CloseableHttpClient httpClient;
 
+  /**
+   * Constructor.
+   *
+   * @param config the {@link Dhis2Config}.
+   */
   public BaseDhis2(Dhis2Config config) {
     Objects.requireNonNull(config, "Config must be specified");
     this.config = config;

src/main/java/org/hisp/dhis/Dhis2.java

@@ -73,6 +73,7 @@
 import org.hisp.dhis.auth.AccessTokenAuthentication;
 import org.hisp.dhis.auth.BasicAuthentication;
 import org.hisp.dhis.auth.CookieAuthentication;
+import org.hisp.dhis.auth.NoAuthentication;
 import org.hisp.dhis.model.AnalyticsTableHook;
 import org.hisp.dhis.model.Attribute;
 import org.hisp.dhis.model.Category;
@@ -240,6 +241,17 @@ public static Dhis2 withCookieAuth(String url, String sessionId) {
     return new Dhis2(new Dhis2Config(url, new CookieAuthentication(sessionId)));
   }
 
+  /**
+   * Creates a {@link Dhis2} instance with no authentication.
+   *
+   * @param url the URL to the DHIS2 instance, do not include the {@code /api} part or a trailing
+   *     {@code /}.
+   * @return a {@link Dhis2} instance.
+   */
+  public static Dhis2 withoutAuth(String url) {
+    return new Dhis2(new Dhis2Config(url, new NoAuthentication()));
+  }
+
   // -------------------------------------------------------------------------
   // Log level
   // -------------------------------------------------------------------------

src/main/java/org/hisp/dhis/auth/Authentication.java

@@ -28,6 +28,7 @@
 package org.hisp.dhis.auth;
 
 import java.io.Serializable;
+import org.apache.commons.lang3.StringUtils;
 
 /** Authentication interface. */
 public interface Authentication extends Serializable {
@@ -44,4 +45,13 @@ public interface Authentication extends Serializable {
    * @return the value of the HTTP header to use for authentication.
    */
   String getHttpHeaderAuthValue();
+
+  /**
+   * Indicates whether authentication details are present.
+   *
+   * @return true if authentication details are present, false otherwise.
+   */
+  default boolean hasAuth() {
+    return StringUtils.isNotEmpty(getHttpHeaderAuthName());
+  }
 }

src/main/java/org/hisp/dhis/auth/NoAuthentication.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2004-2025, University of Oslo
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * Neither the name of the HISP project nor the names of its contributors may
+ * be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.hisp.dhis.auth;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.apache.commons.lang3.StringUtils;
+
+/** Class representing no authentication. */
+@Getter
+@RequiredArgsConstructor
+public class NoAuthentication implements Authentication {
+  @Override
+  public String getHttpHeaderAuthName() {
+    return StringUtils.EMPTY;
+  }
+
+  @Override
+  public String getHttpHeaderAuthValue() {
+    return StringUtils.EMPTY;
+  }
+}

src/main/java/org/hisp/dhis/util/DateTimeUtils.java

@@ -99,6 +99,16 @@ public static Date toDate(LocalDateTime dateTime) {
     return Date.from(dateTime.atZone(ZoneId.systemDefault()).toInstant());
   }
 
+  /**
+   * Returns a {@link java.util.Date} from a {@link java.time.Instant}.
+   *
+   * @param instant the {@link java.time.Instant}.
+   * @return the {@link java.util.Date}.
+   */
+  public static Date toDate(Instant instant) {
+    return Date.from(instant);
+  }
+
   /**
    * Returns a {@link java.util.Date} based on the given string. The string must be on the format
    * <code>yyyy-MM-dd'T'HH:mm:ss.SSS</code>.

src/main/java/org/hisp/dhis/util/HttpUtils.java

@@ -65,7 +65,11 @@ public class HttpUtils {
    */
   public static <T extends HttpUriRequestBase> T withAuth(T request, Dhis2Config config) {
     Authentication auth = config.getAuthentication();
-    request.setHeader(auth.getHttpHeaderAuthName(), auth.getHttpHeaderAuthValue());
+
+    if (auth.hasAuth()) {
+      request.setHeader(auth.getHttpHeaderAuthName(), auth.getHttpHeaderAuthValue());
+    }
+
     return request;
   }
 

src/test/java/org/hisp/dhis/AuthTest.java

@@ -48,10 +48,17 @@ void testWithCookieAuth() {
     assertNotNull(dhis2);
   }
 
+  @Test
   void testWithAccessTokenAuth() {
     Dhis2 dhis2 =
         Dhis2.withAccessTokenAuth(
             "https://play.dhis2.org/demo", "d2pat_2bBQecgNcxrS4EPhBJuRlQkwiLr2ATnC2557514242");
     assertNotNull(dhis2);
   }
+
+  @Test
+  void testWithoutAuth() {
+    Dhis2 dhis2 = Dhis2.withoutAuth("https://play.dhis2.org/demo");
+    assertNotNull(dhis2);
+  }
 }

src/test/java/org/hisp/dhis/util/HttpUtilsTest.java

@@ -28,6 +28,7 @@
 package org.hisp.dhis.util;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
 
 import java.net.URI;
 import java.util.ArrayList;
@@ -39,6 +40,7 @@
 import org.hisp.dhis.auth.AccessTokenAuthentication;
 import org.hisp.dhis.auth.BasicAuthentication;
 import org.hisp.dhis.auth.CookieAuthentication;
+import org.hisp.dhis.auth.NoAuthentication;
 import org.hisp.dhis.support.TestTags;
 import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.api.Test;
@@ -102,6 +104,16 @@ void testWithCookieAuth() throws Exception {
     assertEquals("JSESSIONID=KJH8KJ24fRD3FK491", post.getHeader(HttpHeaders.COOKIE).getValue());
   }
 
+  @Test
+  void testWithoutAuth() throws Exception {
+    HttpPost post = new HttpPost(DEV_URL);
+
+    HttpUtils.withAuth(post, new Dhis2Config(DEV_URL, new NoAuthentication()));
+
+    assertNull(post.getHeader(HttpHeaders.AUTHORIZATION));
+    assertNull(post.getHeader(HttpHeaders.COOKIE));
+  }
+
   @Test
   void testGetBasicAuthString() {
     assertEquals("Basic YWRtaW46ZGlzdHJpY3Q=", HttpUtils.getBasicAuthString("admin", "district"));