Add/remove account group admins (by owner)

src/main/java/org/qora/api/resource/GroupsResource.java

@@ -30,9 +30,11 @@ import org.qora.crypto.Crypto;
 import org.qora.data.group.GroupAdminData;
 import org.qora.data.group.GroupData;
 import org.qora.data.group.GroupMemberData;
+import org.qora.data.transaction.AddGroupAdminTransactionData;
 import org.qora.data.transaction.CreateGroupTransactionData;
 import org.qora.data.transaction.JoinGroupTransactionData;
 import org.qora.data.transaction.LeaveGroupTransactionData;
+import org.qora.data.transaction.RemoveGroupAdminTransactionData;
 import org.qora.data.transaction.UpdateGroupTransactionData;
 import org.qora.repository.DataException;
 import org.qora.repository.Repository;
@@ -40,9 +42,11 @@ import org.qora.repository.RepositoryManager;
 import org.qora.transaction.Transaction;
 import org.qora.transaction.Transaction.ValidationResult;
 import org.qora.transform.TransformationException;
+import org.qora.transform.transaction.AddGroupAdminTransactionTransformer;
 import org.qora.transform.transaction.CreateGroupTransactionTransformer;
 import org.qora.transform.transaction.JoinGroupTransactionTransformer;
 import org.qora.transform.transaction.LeaveGroupTransactionTransformer;
+import org.qora.transform.transaction.RemoveGroupAdminTransactionTransformer;
 import org.qora.transform.transaction.UpdateGroupTransactionTransformer;
 import org.qora.utils.Base58;
 
@@ -246,6 +250,92 @@ public class GroupsResource {
 		}
 	}
 
+	@POST
+	@Path("/addadmin")
+	@Operation(
+		summary = "Build raw, unsigned, ADD_GROUP_ADMIN transaction",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.APPLICATION_JSON,
+				schema = @Schema(
+					implementation = AddGroupAdminTransactionData.class
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				description = "raw, unsigned, ADD_GROUP_ADMIN transaction encoded in Base58",
+				content = @Content(
+					mediaType = MediaType.TEXT_PLAIN,
+					schema = @Schema(
+						type = "string"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.TRANSACTION_INVALID, ApiError.TRANSFORMATION_ERROR, ApiError.REPOSITORY_ISSUE})
+	public String addGroupAdmin(AddGroupAdminTransactionData transactionData) {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			Transaction transaction = Transaction.fromData(repository, transactionData);
+
+			ValidationResult result = transaction.isValidUnconfirmed();
+			if (result != ValidationResult.OK)
+				throw TransactionsResource.createTransactionInvalidException(request, result);
+
+			byte[] bytes = AddGroupAdminTransactionTransformer.toBytes(transactionData);
+			return Base58.encode(bytes);
+		} catch (TransformationException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.TRANSFORMATION_ERROR, e);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+	@POST
+	@Path("/removeadmin")
+	@Operation(
+		summary = "Build raw, unsigned, REMOVE_GROUP_ADMIN transaction",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.APPLICATION_JSON,
+				schema = @Schema(
+					implementation = RemoveGroupAdminTransactionData.class
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				description = "raw, unsigned, REMOVE_GROUP_ADMIN transaction encoded in Base58",
+				content = @Content(
+					mediaType = MediaType.TEXT_PLAIN,
+					schema = @Schema(
+						type = "string"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.TRANSACTION_INVALID, ApiError.TRANSFORMATION_ERROR, ApiError.REPOSITORY_ISSUE})
+	public String removeGroupAdmin(RemoveGroupAdminTransactionData transactionData) {
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			Transaction transaction = Transaction.fromData(repository, transactionData);
+
+			ValidationResult result = transaction.isValidUnconfirmed();
+			if (result != ValidationResult.OK)
+				throw TransactionsResource.createTransactionInvalidException(request, result);
+
+			byte[] bytes = RemoveGroupAdminTransactionTransformer.toBytes(transactionData);
+			return Base58.encode(bytes);
+		} catch (TransformationException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.TRANSFORMATION_ERROR, e);
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@POST
 	@Path("/join")
 	@Operation(

src/main/java/org/qora/data/transaction/AddGroupAdminTransactionData.java

@@ -0,0 +1,63 @@
+package org.qora.data.transaction;
+
+import java.math.BigDecimal;
+
+import javax.xml.bind.Unmarshaller;
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+
+import org.qora.transaction.Transaction.TransactionType;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+// All properties to be converted to JSON via JAX-RS
+@XmlAccessorType(XmlAccessType.FIELD)
+@Schema(allOf = { TransactionData.class })
+public class AddGroupAdminTransactionData extends TransactionData {
+
+	// Properties
+	@Schema(description = "group owner's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	private byte[] ownerPublicKey;
+	@Schema(description = "group name", example = "my-group")
+	private String groupName;
+	@Schema(description = "member to promote to admin", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
+	private String member; 
+
+	// Constructors
+
+	// For JAX-RS
+	protected AddGroupAdminTransactionData() {
+		super(TransactionType.ADD_GROUP_ADMIN);
+	}
+
+	public void afterUnmarshal(Unmarshaller u, Object parent) {
+		this.creatorPublicKey = this.ownerPublicKey;
+	}
+
+	public AddGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String member, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+		super(TransactionType.ADD_GROUP_ADMIN, fee, ownerPublicKey, timestamp, reference, signature);
+
+		this.ownerPublicKey = ownerPublicKey;
+		this.groupName = groupName;
+		this.member = member;
+	}
+
+	public AddGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String member, BigDecimal fee, long timestamp, byte[] reference) {
+		this(ownerPublicKey, groupName, member, fee, timestamp, reference, null);
+	}
+
+	// Getters / setters
+
+	public byte[] getOwnerPublicKey() {
+		return this.ownerPublicKey;
+	}
+
+	public String getGroupName() {
+		return this.groupName;
+	}
+
+	public String getMember() {
+		return this.member;
+	}
+
+}

src/main/java/org/qora/data/transaction/RemoveGroupAdminTransactionData.java

@@ -0,0 +1,85 @@
+package org.qora.data.transaction;
+
+import java.math.BigDecimal;
+
+import javax.xml.bind.Unmarshaller;
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlTransient;
+
+import org.qora.transaction.Transaction.TransactionType;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+// All properties to be converted to JSON via JAX-RS
+@XmlAccessorType(XmlAccessType.FIELD)
+@Schema(allOf = { TransactionData.class })
+public class RemoveGroupAdminTransactionData extends TransactionData {
+
+	// Properties
+	@Schema(description = "group owner's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	private byte[] ownerPublicKey;
+	@Schema(description = "group name", example = "my-group")
+	private String groupName;
+	@Schema(description = "admin to demote", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
+	private String admin; 
+	// For internal use when orphaning
+	@XmlTransient
+	@Schema(hidden = true)
+	private byte[] groupReference;
+
+	// Constructors
+
+	// For JAX-RS
+	protected RemoveGroupAdminTransactionData() {
+		super(TransactionType.REMOVE_GROUP_ADMIN);
+	}
+
+	public void afterUnmarshal(Unmarshaller u, Object parent) {
+		this.creatorPublicKey = this.ownerPublicKey;
+	}
+
+	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+		super(TransactionType.REMOVE_GROUP_ADMIN, fee, ownerPublicKey, timestamp, reference, signature);
+
+		this.ownerPublicKey = ownerPublicKey;
+		this.groupName = groupName;
+		this.admin = admin;
+		this.groupReference = groupReference;
+	}
+
+	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference) {
+		this(ownerPublicKey, groupName, admin, groupReference, fee, timestamp, reference, null);
+	}
+
+	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+		this(ownerPublicKey, groupName, admin, null, fee, timestamp, reference, signature);
+	}
+
+	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, BigDecimal fee, long timestamp, byte[] reference) {
+		this(ownerPublicKey, groupName, admin, null, fee, timestamp, reference, null);
+	}
+
+	// Getters / setters
+
+	public byte[] getOwnerPublicKey() {
+		return this.ownerPublicKey;
+	}
+
+	public String getGroupName() {
+		return this.groupName;
+	}
+
+	public String getAdmin() {
+		return this.admin;
+	}
+
+	public byte[] getGroupReference() {
+		return this.groupReference;
+	}
+
+	public void setGroupReference(byte[] groupReference) {
+		this.groupReference = groupReference;
+	}
+
+}

src/main/java/org/qora/data/transaction/TransactionData.java

@@ -34,6 +34,7 @@ import io.swagger.v3.oas.annotations.media.Schema.AccessMode;
 	CreateOrderTransactionData.class, CancelOrderTransactionData.class,
 	MultiPaymentTransactionData.class, DeployATTransactionData.class, MessageTransactionData.class, ATTransactionData.class,
 	CreateGroupTransactionData.class, UpdateGroupTransactionData.class,
+	AddGroupAdminTransactionData.class, RemoveGroupAdminTransactionData.class,
 	JoinGroupTransactionData.class, LeaveGroupTransactionData.class
 })
 //All properties to be converted to JSON via JAX-RS

src/main/java/org/qora/group/Group.java

@@ -7,9 +7,11 @@ import org.qora.account.PublicKeyAccount;
 import org.qora.data.group.GroupAdminData;
 import org.qora.data.group.GroupData;
 import org.qora.data.group.GroupMemberData;
+import org.qora.data.transaction.AddGroupAdminTransactionData;
 import org.qora.data.transaction.CreateGroupTransactionData;
 import org.qora.data.transaction.JoinGroupTransactionData;
 import org.qora.data.transaction.LeaveGroupTransactionData;
+import org.qora.data.transaction.RemoveGroupAdminTransactionData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.data.transaction.UpdateGroupTransactionData;
 import org.qora.repository.DataException;
@@ -165,6 +167,38 @@ public class Group {
 		}
 	}
 
+	public void promoteToAdmin(AddGroupAdminTransactionData addGroupAdminTransactionData) throws DataException {
+		GroupAdminData groupAdminData = new GroupAdminData(addGroupAdminTransactionData.getGroupName(), addGroupAdminTransactionData.getMember(), addGroupAdminTransactionData.getSignature());
+		this.repository.getGroupRepository().save(groupAdminData);
+	}
+
+	public void unpromoteToAdmin(AddGroupAdminTransactionData addGroupAdminTransactionData) throws DataException {
+		this.repository.getGroupRepository().deleteAdmin(addGroupAdminTransactionData.getGroupName(), addGroupAdminTransactionData.getMember());
+	}
+
+	public void demoteFromAdmin(RemoveGroupAdminTransactionData removeGroupAdminTransactionData) throws DataException {
+		GroupRepository groupRepository = this.repository.getGroupRepository();
+		String groupName = removeGroupAdminTransactionData.getGroupName();
+		String admin = removeGroupAdminTransactionData.getAdmin();
+
+		// Save admin's promotion transaction reference for orphaning purposes
+		GroupAdminData groupAdminData = groupRepository.getAdmin(groupName, admin);
+		removeGroupAdminTransactionData.setGroupReference(groupAdminData.getGroupReference());
+
+		// Demote
+		groupRepository.deleteAdmin(groupName, admin);
+	}
+
+	public void undemoteFromAdmin(RemoveGroupAdminTransactionData removeGroupAdminTransactionData) throws DataException {
+		GroupRepository groupRepository = this.repository.getGroupRepository();
+		String groupName = removeGroupAdminTransactionData.getGroupName();
+		String admin = removeGroupAdminTransactionData.getAdmin();
+
+		// Rebuild admin entry using stored promotion transaction reference
+		GroupAdminData groupAdminData = new GroupAdminData(groupName, admin, removeGroupAdminTransactionData.getGroupReference());
+		groupRepository.save(groupAdminData);
+	}
+
 	public void join(JoinGroupTransactionData joinGroupTransactionData) throws DataException {
 		Account joiner = new PublicKeyAccount(this.repository, joinGroupTransactionData.getJoinerPublicKey());
 

src/main/java/org/qora/repository/hsqldb/HSQLDBDatabaseUpdates.java

@@ -452,6 +452,12 @@ public class HSQLDBDatabaseUpdates {
 							+ "new_owner QoraAddress NOT NULL, new_description GenericDescription NOT NULL, new_is_open BOOLEAN NOT NULL, group_reference Signature, "
 							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 
+					// Account group add/remove admin transactions
+					stmt.execute("CREATE TABLE AddGroupAdminTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, address QoraAddress NOT NULL, "
+							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+					stmt.execute("CREATE TABLE RemoveGroupAdminTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, admin QoraAddress NOT NULL, "
+							+ "group_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+
 					// Account group join/leave transactions
 					stmt.execute("CREATE TABLE JoinGroupTransactions (signature Signature, joiner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, "
 							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBAddGroupAdminTransactionRepository.java

@@ -0,0 +1,49 @@
+package org.qora.repository.hsqldb.transaction;
+
+import java.math.BigDecimal;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+import org.qora.data.transaction.AddGroupAdminTransactionData;
+import org.qora.data.transaction.TransactionData;
+import org.qora.repository.DataException;
+import org.qora.repository.hsqldb.HSQLDBRepository;
+import org.qora.repository.hsqldb.HSQLDBSaver;
+
+public class HSQLDBAddGroupAdminTransactionRepository extends HSQLDBTransactionRepository {
+
+	public HSQLDBAddGroupAdminTransactionRepository(HSQLDBRepository repository) {
+		this.repository = repository;
+	}
+
+	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_name, address FROM AddGroupAdminTransactions WHERE signature = ?", signature)) {
+			if (resultSet == null)
+				return null;
+
+			String groupName = resultSet.getString(1);
+			String member = resultSet.getString(2);
+
+			return new AddGroupAdminTransactionData(creatorPublicKey, groupName, member, fee, timestamp, reference, signature);
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch add group admin transaction from repository", e);
+		}
+	}
+
+	@Override
+	public void save(TransactionData transactionData) throws DataException {
+		AddGroupAdminTransactionData addGroupAdminTransactionData = (AddGroupAdminTransactionData) transactionData;
+
+		HSQLDBSaver saveHelper = new HSQLDBSaver("AddGroupAdminTransactions");
+
+		saveHelper.bind("signature", addGroupAdminTransactionData.getSignature()).bind("owner", addGroupAdminTransactionData.getOwnerPublicKey())
+				.bind("group_name", addGroupAdminTransactionData.getGroupName()).bind("address", addGroupAdminTransactionData.getMember());
+
+		try {
+			saveHelper.execute(this.repository);
+		} catch (SQLException e) {
+			throw new DataException("Unable to save add group admin transaction into repository", e);
+		}
+	}
+
+}

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBRemoveGroupAdminTransactionRepository.java

@@ -0,0 +1,52 @@
+package org.qora.repository.hsqldb.transaction;
+
+import java.math.BigDecimal;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+import org.qora.data.transaction.RemoveGroupAdminTransactionData;
+import org.qora.data.transaction.TransactionData;
+import org.qora.repository.DataException;
+import org.qora.repository.hsqldb.HSQLDBRepository;
+import org.qora.repository.hsqldb.HSQLDBSaver;
+
+public class HSQLDBRemoveGroupAdminTransactionRepository extends HSQLDBTransactionRepository {
+
+	public HSQLDBRemoveGroupAdminTransactionRepository(HSQLDBRepository repository) {
+		this.repository = repository;
+	}
+
+	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
+		try (ResultSet resultSet = this.repository
+				.checkedExecute("SELECT group_name, admin, group_reference FROM RemoveGroupAdminTransactions WHERE signature = ?", signature)) {
+			if (resultSet == null)
+				return null;
+
+			String groupName = resultSet.getString(1);
+			String admin = resultSet.getString(2);
+			byte[] groupReference = resultSet.getBytes(3);
+
+			return new RemoveGroupAdminTransactionData(creatorPublicKey, groupName, admin, groupReference, fee, timestamp, reference, signature);
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch remove group admin transaction from repository", e);
+		}
+	}
+
+	@Override
+	public void save(TransactionData transactionData) throws DataException {
+		RemoveGroupAdminTransactionData removeGroupAdminTransactionData = (RemoveGroupAdminTransactionData) transactionData;
+
+		HSQLDBSaver saveHelper = new HSQLDBSaver("RemoveGroupAdminTransactions");
+
+		saveHelper.bind("signature", removeGroupAdminTransactionData.getSignature()).bind("owner", removeGroupAdminTransactionData.getOwnerPublicKey())
+				.bind("group_name", removeGroupAdminTransactionData.getGroupName()).bind("admin", removeGroupAdminTransactionData.getAdmin())
+				.bind("group_reference", removeGroupAdminTransactionData.getGroupReference());
+
+		try {
+			saveHelper.execute(this.repository);
+		} catch (SQLException e) {
+			throw new DataException("Unable to save remove group admin transaction into repository", e);
+		}
+	}
+
+}

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBTransactionRepository.java

@@ -43,6 +43,8 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 	private HSQLDBATTransactionRepository atTransactionRepository;
 	private HSQLDBCreateGroupTransactionRepository createGroupTransactionRepository;
 	private HSQLDBUpdateGroupTransactionRepository updateGroupTransactionRepository;
+	private HSQLDBAddGroupAdminTransactionRepository addGroupAdminTransactionRepository;
+	private HSQLDBRemoveGroupAdminTransactionRepository removeGroupAdminTransactionRepository;
 	private HSQLDBJoinGroupTransactionRepository joinGroupTransactionRepository;
 	private HSQLDBLeaveGroupTransactionRepository leaveGroupTransactionRepository;
 
@@ -68,6 +70,8 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 		this.atTransactionRepository = new HSQLDBATTransactionRepository(repository);
 		this.createGroupTransactionRepository = new HSQLDBCreateGroupTransactionRepository(repository);
 		this.updateGroupTransactionRepository = new HSQLDBUpdateGroupTransactionRepository(repository);
+		this.addGroupAdminTransactionRepository = new HSQLDBAddGroupAdminTransactionRepository(repository);
+		this.removeGroupAdminTransactionRepository = new HSQLDBRemoveGroupAdminTransactionRepository(repository);
 		this.joinGroupTransactionRepository = new HSQLDBJoinGroupTransactionRepository(repository);
 		this.leaveGroupTransactionRepository = new HSQLDBLeaveGroupTransactionRepository(repository);
 	}
@@ -202,6 +206,12 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 			case UPDATE_GROUP:
 				return this.updateGroupTransactionRepository.fromBase(signature, reference, creatorPublicKey, timestamp, fee);
 
+			case ADD_GROUP_ADMIN:
+				return this.addGroupAdminTransactionRepository.fromBase(signature, reference, creatorPublicKey, timestamp, fee);
+
+			case REMOVE_GROUP_ADMIN:
+				return this.removeGroupAdminTransactionRepository.fromBase(signature, reference, creatorPublicKey, timestamp, fee);
+
 			case JOIN_GROUP:
 				return this.joinGroupTransactionRepository.fromBase(signature, reference, creatorPublicKey, timestamp, fee);
 
@@ -536,6 +546,14 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 				this.updateGroupTransactionRepository.save(transactionData);
 				break;
 
+			case ADD_GROUP_ADMIN:
+				this.addGroupAdminTransactionRepository.save(transactionData);
+				break;
+
+			case REMOVE_GROUP_ADMIN:
+				this.removeGroupAdminTransactionRepository.save(transactionData);
+				break;
+
 			case JOIN_GROUP:
 				this.joinGroupTransactionRepository.save(transactionData);
 				break;

src/main/java/org/qora/transaction/AddGroupAdminTransaction.java

@@ -0,0 +1,157 @@
+package org.qora.transaction;
+
+import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.qora.account.Account;
+import org.qora.account.PublicKeyAccount;
+import org.qora.asset.Asset;
+import org.qora.data.transaction.AddGroupAdminTransactionData;
+import org.qora.data.group.GroupData;
+import org.qora.data.transaction.TransactionData;
+import org.qora.group.Group;
+import org.qora.repository.DataException;
+import org.qora.repository.Repository;
+
+import com.google.common.base.Utf8;
+
+public class AddGroupAdminTransaction extends Transaction {
+
+	// Properties
+	private AddGroupAdminTransactionData addGroupAdminTransactionData;
+
+	// Constructors
+
+	public AddGroupAdminTransaction(Repository repository, TransactionData transactionData) {
+		super(repository, transactionData);
+
+		this.addGroupAdminTransactionData = (AddGroupAdminTransactionData) this.transactionData;
+	}
+
+	// More information
+
+	@Override
+	public List<Account> getRecipientAccounts() throws DataException {
+		return Collections.emptyList();
+	}
+
+	@Override
+	public boolean isInvolved(Account account) throws DataException {
+		String address = account.getAddress();
+
+		if (address.equals(this.getOwner().getAddress()))
+			return true;
+
+		if (address.equals(this.getMember().getAddress()))
+			return true;
+
+		return false;
+	}
+
+	@Override
+	public BigDecimal getAmount(Account account) throws DataException {
+		String address = account.getAddress();
+		BigDecimal amount = BigDecimal.ZERO.setScale(8);
+
+		if (address.equals(this.getOwner().getAddress()))
+			amount = amount.subtract(this.transactionData.getFee());
+
+		return amount;
+	}
+
+	// Navigation
+
+	public Account getOwner() throws DataException {
+		return new PublicKeyAccount(this.repository, this.addGroupAdminTransactionData.getOwnerPublicKey());
+	}
+
+	public Account getMember() throws DataException {
+		return new Account(this.repository, this.addGroupAdminTransactionData.getMember());
+	}
+
+	// Processing
+
+	@Override
+	public ValidationResult isValid() throws DataException {
+		// Check group name size bounds
+		int groupNameLength = Utf8.encodedLength(addGroupAdminTransactionData.getGroupName());
+		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
+			return ValidationResult.INVALID_NAME_LENGTH;
+
+		// Check group name is lowercase
+		if (!addGroupAdminTransactionData.getGroupName().equals(addGroupAdminTransactionData.getGroupName().toLowerCase()))
+			return ValidationResult.NAME_NOT_LOWER_CASE;
+
+		GroupData groupData = this.repository.getGroupRepository().fromGroupName(addGroupAdminTransactionData.getGroupName());
+
+		// Check group exists
+		if (groupData == null)
+			return ValidationResult.GROUP_DOES_NOT_EXIST;
+
+		Account owner = getOwner();
+
+		// Check transaction's public key matches group's current owner
+		if (!owner.getAddress().equals(groupData.getOwner()))
+			return ValidationResult.INVALID_GROUP_OWNER;
+
+		// Check address is a member
+		if (!this.repository.getGroupRepository().memberExists(addGroupAdminTransactionData.getGroupName(), owner.getAddress()))
+			return ValidationResult.NOT_GROUP_MEMBER;
+
+		Account member = getMember();
+
+		// Check member is not already an admin
+		if (this.repository.getGroupRepository().adminExists(addGroupAdminTransactionData.getGroupName(), member.getAddress()))
+			return ValidationResult.ALREADY_GROUP_ADMIN;
+
+		// Check fee is positive
+		if (addGroupAdminTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
+			return ValidationResult.NEGATIVE_FEE;
+
+		if (!Arrays.equals(owner.getLastReference(), addGroupAdminTransactionData.getReference()))
+			return ValidationResult.INVALID_REFERENCE;
+
+		// Check creator has enough funds
+		if (owner.getConfirmedBalance(Asset.QORA).compareTo(addGroupAdminTransactionData.getFee()) < 0)
+			return ValidationResult.NO_BALANCE;
+
+		return ValidationResult.OK;
+	}
+
+	@Override
+	public void process() throws DataException {
+		// Update Group adminship
+		Group group = new Group(this.repository, addGroupAdminTransactionData.getGroupName());
+		group.promoteToAdmin(addGroupAdminTransactionData);
+
+		// Save this transaction
+		this.repository.getTransactionRepository().save(addGroupAdminTransactionData);
+
+		// Update owner's balance
+		Account owner = getOwner();
+		owner.setConfirmedBalance(Asset.QORA, owner.getConfirmedBalance(Asset.QORA).subtract(addGroupAdminTransactionData.getFee()));
+
+		// Update owner's reference
+		owner.setLastReference(addGroupAdminTransactionData.getSignature());
+	}
+
+	@Override
+	public void orphan() throws DataException {
+		// Revert group adminship
+		Group group = new Group(this.repository, addGroupAdminTransactionData.getGroupName());
+		group.unpromoteToAdmin(addGroupAdminTransactionData);
+
+		// Delete this transaction itself
+		this.repository.getTransactionRepository().delete(addGroupAdminTransactionData);
+
+		// Update owner's balance
+		Account owner = getOwner();
+		owner.setConfirmedBalance(Asset.QORA, owner.getConfirmedBalance(Asset.QORA).add(addGroupAdminTransactionData.getFee()));
+
+		// Update owner's reference
+		owner.setLastReference(addGroupAdminTransactionData.getReference());
+	}
+
+}

src/main/java/org/qora/transaction/RemoveGroupAdminTransaction.java

@@ -0,0 +1,153 @@
+package org.qora.transaction;
+
+import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.qora.account.Account;
+import org.qora.account.PublicKeyAccount;
+import org.qora.asset.Asset;
+import org.qora.data.transaction.RemoveGroupAdminTransactionData;
+import org.qora.data.group.GroupData;
+import org.qora.data.transaction.TransactionData;
+import org.qora.group.Group;
+import org.qora.repository.DataException;
+import org.qora.repository.Repository;
+
+import com.google.common.base.Utf8;
+
+public class RemoveGroupAdminTransaction extends Transaction {
+
+	// Properties
+	private RemoveGroupAdminTransactionData removeGroupAdminTransactionData;
+
+	// Constructors
+
+	public RemoveGroupAdminTransaction(Repository repository, TransactionData transactionData) {
+		super(repository, transactionData);
+
+		this.removeGroupAdminTransactionData = (RemoveGroupAdminTransactionData) this.transactionData;
+	}
+
+	// More information
+
+	@Override
+	public List<Account> getRecipientAccounts() throws DataException {
+		return Collections.emptyList();
+	}
+
+	@Override
+	public boolean isInvolved(Account account) throws DataException {
+		String address = account.getAddress();
+
+		if (address.equals(this.getOwner().getAddress()))
+			return true;
+
+		if (address.equals(this.getAdmin().getAddress()))
+			return true;
+
+		return false;
+	}
+
+	@Override
+	public BigDecimal getAmount(Account account) throws DataException {
+		String address = account.getAddress();
+		BigDecimal amount = BigDecimal.ZERO.setScale(8);
+
+		if (address.equals(this.getOwner().getAddress()))
+			amount = amount.subtract(this.transactionData.getFee());
+
+		return amount;
+	}
+
+	// Navigation
+
+	public Account getOwner() throws DataException {
+		return new PublicKeyAccount(this.repository, this.removeGroupAdminTransactionData.getOwnerPublicKey());
+	}
+
+	public Account getAdmin() throws DataException {
+		return new Account(this.repository, this.removeGroupAdminTransactionData.getAdmin());
+	}
+
+	// Processing
+
+	@Override
+	public ValidationResult isValid() throws DataException {
+		// Check group name size bounds
+		int groupNameLength = Utf8.encodedLength(removeGroupAdminTransactionData.getGroupName());
+		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
+			return ValidationResult.INVALID_NAME_LENGTH;
+
+		// Check group name is lowercase
+		if (!removeGroupAdminTransactionData.getGroupName().equals(removeGroupAdminTransactionData.getGroupName().toLowerCase()))
+			return ValidationResult.NAME_NOT_LOWER_CASE;
+
+		GroupData groupData = this.repository.getGroupRepository().fromGroupName(removeGroupAdminTransactionData.getGroupName());
+
+		// Check group exists
+		if (groupData == null)
+			return ValidationResult.GROUP_DOES_NOT_EXIST;
+
+		Account owner = getOwner();
+
+		// Check transaction's public key matches group's current owner
+		if (!owner.getAddress().equals(groupData.getOwner()))
+			return ValidationResult.INVALID_GROUP_OWNER;
+
+		Account admin = getAdmin();
+
+		// Check member is an admin
+		if (!this.repository.getGroupRepository().adminExists(removeGroupAdminTransactionData.getGroupName(), admin.getAddress()))
+			return ValidationResult.NOT_GROUP_ADMIN;
+
+		// Check fee is positive
+		if (removeGroupAdminTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
+			return ValidationResult.NEGATIVE_FEE;
+
+		if (!Arrays.equals(owner.getLastReference(), removeGroupAdminTransactionData.getReference()))
+			return ValidationResult.INVALID_REFERENCE;
+
+		// Check creator has enough funds
+		if (owner.getConfirmedBalance(Asset.QORA).compareTo(removeGroupAdminTransactionData.getFee()) < 0)
+			return ValidationResult.NO_BALANCE;
+
+		return ValidationResult.OK;
+	}
+
+	@Override
+	public void process() throws DataException {
+		// Update Group adminship
+		Group group = new Group(this.repository, removeGroupAdminTransactionData.getGroupName());
+		group.demoteFromAdmin(removeGroupAdminTransactionData);
+
+		// Save this transaction
+		this.repository.getTransactionRepository().save(removeGroupAdminTransactionData);
+
+		// Update owner's balance
+		Account owner = getOwner();
+		owner.setConfirmedBalance(Asset.QORA, owner.getConfirmedBalance(Asset.QORA).subtract(removeGroupAdminTransactionData.getFee()));
+
+		// Update owner's reference
+		owner.setLastReference(removeGroupAdminTransactionData.getSignature());
+	}
+
+	@Override
+	public void orphan() throws DataException {
+		// Revert group adminship
+		Group group = new Group(this.repository, removeGroupAdminTransactionData.getGroupName());
+		group.undemoteFromAdmin(removeGroupAdminTransactionData);
+
+		// Delete this transaction itself
+		this.repository.getTransactionRepository().delete(removeGroupAdminTransactionData);
+
+		// Update owner's balance
+		Account owner = getOwner();
+		owner.setConfirmedBalance(Asset.QORA, owner.getConfirmedBalance(Asset.QORA).add(removeGroupAdminTransactionData.getFee()));
+
+		// Update owner's reference
+		owner.setLastReference(removeGroupAdminTransactionData.getReference());
+	}
+
+}

src/main/java/org/qora/transaction/Transaction.java

@@ -131,6 +131,8 @@ public abstract class Transaction {
 		ALREADY_GROUP_MEMBER(51),
 		GROUP_OWNER_CANNOT_LEAVE(52),
 		NOT_GROUP_MEMBER(53),
+		ALREADY_GROUP_ADMIN(54),
+		NOT_GROUP_ADMIN(55),
 		NOT_YET_RELEASED(1000);
 
 		public final int value;
@@ -236,6 +238,12 @@ public abstract class Transaction {
 			case UPDATE_GROUP:
 				return new UpdateGroupTransaction(repository, transactionData);
 
+			case ADD_GROUP_ADMIN:
+				return new AddGroupAdminTransaction(repository, transactionData);
+
+			case REMOVE_GROUP_ADMIN:
+				return new RemoveGroupAdminTransaction(repository, transactionData);
+
 			case JOIN_GROUP:
 				return new JoinGroupTransaction(repository, transactionData);
 

src/main/java/org/qora/transform/transaction/AddGroupAdminTransactionTransformer.java

@@ -0,0 +1,104 @@
+package org.qora.transform.transaction;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.nio.ByteBuffer;
+
+import org.json.simple.JSONObject;
+import org.qora.account.PublicKeyAccount;
+import org.qora.data.transaction.AddGroupAdminTransactionData;
+import org.qora.data.transaction.TransactionData;
+import org.qora.group.Group;
+import org.qora.transform.TransformationException;
+import org.qora.utils.Serialization;
+
+import com.google.common.base.Utf8;
+import com.google.common.hash.HashCode;
+import com.google.common.primitives.Ints;
+import com.google.common.primitives.Longs;
+
+public class AddGroupAdminTransactionTransformer extends TransactionTransformer {
+
+	// Property lengths
+	private static final int OWNER_LENGTH = PUBLIC_KEY_LENGTH;
+	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
+
+	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH;
+
+	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
+		long timestamp = byteBuffer.getLong();
+
+		byte[] reference = new byte[REFERENCE_LENGTH];
+		byteBuffer.get(reference);
+
+		byte[] ownerPublicKey = Serialization.deserializePublicKey(byteBuffer);
+
+		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+
+		String member = Serialization.deserializeAddress(byteBuffer);
+
+		BigDecimal fee = Serialization.deserializeBigDecimal(byteBuffer);
+
+		byte[] signature = new byte[SIGNATURE_LENGTH];
+		byteBuffer.get(signature);
+
+		return new AddGroupAdminTransactionData(ownerPublicKey, groupName, member, fee, timestamp, reference, signature);
+	}
+
+	public static int getDataLength(TransactionData transactionData) throws TransformationException {
+		AddGroupAdminTransactionData addGroupAdminTransactionData = (AddGroupAdminTransactionData) transactionData;
+
+		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(addGroupAdminTransactionData.getGroupName());
+
+		return dataLength;
+	}
+
+	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
+		try {
+			AddGroupAdminTransactionData addGroupAdminTransactionData = (AddGroupAdminTransactionData) transactionData;
+
+			ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+			bytes.write(Ints.toByteArray(addGroupAdminTransactionData.getType().value));
+			bytes.write(Longs.toByteArray(addGroupAdminTransactionData.getTimestamp()));
+			bytes.write(addGroupAdminTransactionData.getReference());
+
+			bytes.write(addGroupAdminTransactionData.getCreatorPublicKey());
+			Serialization.serializeSizedString(bytes, addGroupAdminTransactionData.getGroupName());
+			Serialization.serializeAddress(bytes, addGroupAdminTransactionData.getMember());
+
+			Serialization.serializeBigDecimal(bytes, addGroupAdminTransactionData.getFee());
+
+			if (addGroupAdminTransactionData.getSignature() != null)
+				bytes.write(addGroupAdminTransactionData.getSignature());
+
+			return bytes.toByteArray();
+		} catch (IOException | ClassCastException e) {
+			throw new TransformationException(e);
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	public static JSONObject toJSON(TransactionData transactionData) throws TransformationException {
+		JSONObject json = TransactionTransformer.getBaseJSON(transactionData);
+
+		try {
+			AddGroupAdminTransactionData addGroupAdminTransactionData = (AddGroupAdminTransactionData) transactionData;
+
+			byte[] ownerPublicKey = addGroupAdminTransactionData.getOwnerPublicKey();
+
+			json.put("owner", PublicKeyAccount.getAddress(ownerPublicKey));
+			json.put("ownerPublicKey", HashCode.fromBytes(ownerPublicKey).toString());
+
+			json.put("groupName", addGroupAdminTransactionData.getGroupName());
+			json.put("member", addGroupAdminTransactionData.getMember());
+		} catch (ClassCastException e) {
+			throw new TransformationException(e);
+		}
+
+		return json;
+	}
+
+}

src/main/java/org/qora/transform/transaction/RemoveGroupAdminTransactionTransformer.java

@@ -0,0 +1,104 @@
+package org.qora.transform.transaction;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.nio.ByteBuffer;
+
+import org.json.simple.JSONObject;
+import org.qora.account.PublicKeyAccount;
+import org.qora.data.transaction.RemoveGroupAdminTransactionData;
+import org.qora.data.transaction.TransactionData;
+import org.qora.group.Group;
+import org.qora.transform.TransformationException;
+import org.qora.utils.Serialization;
+
+import com.google.common.base.Utf8;
+import com.google.common.hash.HashCode;
+import com.google.common.primitives.Ints;
+import com.google.common.primitives.Longs;
+
+public class RemoveGroupAdminTransactionTransformer extends TransactionTransformer {
+
+	// Property lengths
+	private static final int OWNER_LENGTH = PUBLIC_KEY_LENGTH;
+	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
+
+	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH;
+
+	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
+		long timestamp = byteBuffer.getLong();
+
+		byte[] reference = new byte[REFERENCE_LENGTH];
+		byteBuffer.get(reference);
+
+		byte[] ownerPublicKey = Serialization.deserializePublicKey(byteBuffer);
+
+		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+
+		String admin = Serialization.deserializeAddress(byteBuffer);
+
+		BigDecimal fee = Serialization.deserializeBigDecimal(byteBuffer);
+
+		byte[] signature = new byte[SIGNATURE_LENGTH];
+		byteBuffer.get(signature);
+
+		return new RemoveGroupAdminTransactionData(ownerPublicKey, groupName, admin, fee, timestamp, reference, signature);
+	}
+
+	public static int getDataLength(TransactionData transactionData) throws TransformationException {
+		RemoveGroupAdminTransactionData removeGroupAdminTransactionData = (RemoveGroupAdminTransactionData) transactionData;
+
+		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(removeGroupAdminTransactionData.getGroupName());
+
+		return dataLength;
+	}
+
+	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
+		try {
+			RemoveGroupAdminTransactionData removeGroupAdminTransactionData = (RemoveGroupAdminTransactionData) transactionData;
+
+			ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+			bytes.write(Ints.toByteArray(removeGroupAdminTransactionData.getType().value));
+			bytes.write(Longs.toByteArray(removeGroupAdminTransactionData.getTimestamp()));
+			bytes.write(removeGroupAdminTransactionData.getReference());
+
+			bytes.write(removeGroupAdminTransactionData.getCreatorPublicKey());
+			Serialization.serializeSizedString(bytes, removeGroupAdminTransactionData.getGroupName());
+			Serialization.serializeAddress(bytes, removeGroupAdminTransactionData.getAdmin());
+
+			Serialization.serializeBigDecimal(bytes, removeGroupAdminTransactionData.getFee());
+
+			if (removeGroupAdminTransactionData.getSignature() != null)
+				bytes.write(removeGroupAdminTransactionData.getSignature());
+
+			return bytes.toByteArray();
+		} catch (IOException | ClassCastException e) {
+			throw new TransformationException(e);
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	public static JSONObject toJSON(TransactionData transactionData) throws TransformationException {
+		JSONObject json = TransactionTransformer.getBaseJSON(transactionData);
+
+		try {
+			RemoveGroupAdminTransactionData removeGroupAdminTransactionData = (RemoveGroupAdminTransactionData) transactionData;
+
+			byte[] ownerPublicKey = removeGroupAdminTransactionData.getOwnerPublicKey();
+
+			json.put("owner", PublicKeyAccount.getAddress(ownerPublicKey));
+			json.put("ownerPublicKey", HashCode.fromBytes(ownerPublicKey).toString());
+
+			json.put("groupName", removeGroupAdminTransactionData.getGroupName());
+			json.put("admin", removeGroupAdminTransactionData.getAdmin());
+		} catch (ClassCastException e) {
+			throw new TransformationException(e);
+		}
+
+		return json;
+	}
+
+}

src/main/java/org/qora/transform/transaction/TransactionTransformer.java

@@ -100,6 +100,12 @@ public class TransactionTransformer extends Transformer {
 				case UPDATE_GROUP:
 					return UpdateGroupTransactionTransformer.fromByteBuffer(byteBuffer);
 
+				case ADD_GROUP_ADMIN:
+					return AddGroupAdminTransactionTransformer.fromByteBuffer(byteBuffer);
+
+				case REMOVE_GROUP_ADMIN:
+					return RemoveGroupAdminTransactionTransformer.fromByteBuffer(byteBuffer);
+
 				case JOIN_GROUP:
 					return JoinGroupTransactionTransformer.fromByteBuffer(byteBuffer);
 
@@ -173,6 +179,12 @@ public class TransactionTransformer extends Transformer {
 			case UPDATE_GROUP:
 				return UpdateGroupTransactionTransformer.getDataLength(transactionData);
 
+			case ADD_GROUP_ADMIN:
+				return AddGroupAdminTransactionTransformer.getDataLength(transactionData);
+
+			case REMOVE_GROUP_ADMIN:
+				return RemoveGroupAdminTransactionTransformer.getDataLength(transactionData);
+
 			case JOIN_GROUP:
 				return JoinGroupTransactionTransformer.getDataLength(transactionData);
 
@@ -243,6 +255,12 @@ public class TransactionTransformer extends Transformer {
 			case UPDATE_GROUP:
 				return UpdateGroupTransactionTransformer.toBytes(transactionData);
 
+			case ADD_GROUP_ADMIN:
+				return AddGroupAdminTransactionTransformer.toBytes(transactionData);
+
+			case REMOVE_GROUP_ADMIN:
+				return RemoveGroupAdminTransactionTransformer.toBytes(transactionData);
+
 			case JOIN_GROUP:
 				return JoinGroupTransactionTransformer.toBytes(transactionData);
 
@@ -322,6 +340,12 @@ public class TransactionTransformer extends Transformer {
 			case UPDATE_GROUP:
 				return UpdateGroupTransactionTransformer.toBytesForSigningImpl(transactionData);
 
+			case ADD_GROUP_ADMIN:
+				return AddGroupAdminTransactionTransformer.toBytesForSigningImpl(transactionData);
+
+			case REMOVE_GROUP_ADMIN:
+				return RemoveGroupAdminTransactionTransformer.toBytesForSigningImpl(transactionData);
+
 			case JOIN_GROUP:
 				return JoinGroupTransactionTransformer.toBytesForSigningImpl(transactionData);
 
@@ -413,6 +437,12 @@ public class TransactionTransformer extends Transformer {
 			case UPDATE_GROUP:
 				return UpdateGroupTransactionTransformer.toJSON(transactionData);
 
+			case ADD_GROUP_ADMIN:
+				return AddGroupAdminTransactionTransformer.toJSON(transactionData);
+
+			case REMOVE_GROUP_ADMIN:
+				return RemoveGroupAdminTransactionTransformer.toJSON(transactionData);
+
 			case JOIN_GROUP:
 				return JoinGroupTransactionTransformer.toJSON(transactionData);