Add billing data export api

fixes https://gitlab.com/entgra/product-iots/-/issues/1226

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/beans/DeviceList.java

@@ -32,6 +32,12 @@ public class DeviceList extends BasePaginatedResult {
     @ApiModelProperty(name = "totalCost", value = "Total cost of all devices per tenant", required = false)
     private double totalCost;
 
+    @ApiModelProperty(name = "message", value = "Send information text to the billing UI", required = false)
+    private String message;
+
+    @ApiModelProperty(name = "billedDateIsValid", value = "Check if user entered date is valid", required = false)
+    private boolean billedDateIsValid;
+
     @ApiModelProperty(value = "List of devices returned")
     @JsonProperty("devices")
     public List<Device> getList() {
@@ -42,6 +48,22 @@ public class DeviceList extends BasePaginatedResult {
         this.devices = devices;
     }
 
+    public boolean isBilledDateIsValid() {
+        return billedDateIsValid;
+    }
+
+    public void setBilledDateIsValid(boolean billedDateIsValid) {
+        this.billedDateIsValid = billedDateIsValid;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+
     public double getTotalCost() {
         return totalCost;
     }

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/DeviceManagementService.java

@@ -432,6 +432,83 @@ public interface DeviceManagementService {
             @QueryParam("limit")
                     int limit);
 
+
+    @GET
+    @Path("/billing/file")
+    @Produces(MediaType.APPLICATION_JSON)
+    @ApiOperation(
+            produces = MediaType.APPLICATION_JSON,
+            httpMethod = "GET",
+            value = "Getting Cost details of devices in a tenant",
+            notes = "Provides individual cost and total cost of all devices per tenant.",
+            tags = "Device Management",
+            extensions = {
+                    @Extension(properties = {
+                            @ExtensionProperty(name = Constants.SCOPE, value = "perm:devices:view")
+                    })
+            }
+    )
+    @ApiResponses(value = {
+            @ApiResponse(code = 200, message = "OK. \n Successfully fetched the list of devices.",
+                    response = DeviceList.class,
+                    responseHeaders = {
+                            @ResponseHeader(
+                                    name = "Content-Type",
+                                    description = "The content type of the body"),
+                            @ResponseHeader(
+                                    name = "Content-Disposition",
+                                    description = "The content disposition of the body"),
+                            @ResponseHeader(
+                                    name = "ETag",
+                                    description = "Entity Tag of the response resource.\n" +
+                                            "Used by caches, or in conditional requests."),
+                            @ResponseHeader(
+                                    name = "Last-Modified",
+                                    description = "Date and time the resource was last modified.\n" +
+                                            "Used by caches, or in conditional requests."),
+                    }),
+            @ApiResponse(
+                    code = 304,
+                    message = "Not Modified. \n Empty body because the client already has the latest version of " +
+                            "the requested resource.\n"),
+            @ApiResponse(
+                    code = 400,
+                    message = "The incoming request has more than one selection criteria defined via the query parameters.",
+                    response = ErrorResponse.class),
+            @ApiResponse(
+                    code = 404,
+                    message = "The search criteria did not match any device registered with the server.",
+                    response = ErrorResponse.class),
+            @ApiResponse(
+                    code = 406,
+                    message = "Not Acceptable.\n The requested media type is not supported."),
+            @ApiResponse(
+                    code = 500,
+                    message = "Internal Server Error. \n Server error occurred while fetching the device list.",
+                    response = ErrorResponse.class)
+    })
+    Response exportBilling(
+            @ApiParam(
+                    name = "tenantDomain",
+                    value = "The tenant domain.",
+                    required = false)
+                    String tenantDomain,
+            @ApiParam(
+                    name = "startDate",
+                    value = "The start date.",
+                    required = false)
+                    Timestamp startDate,
+            @ApiParam(
+                    name = "endDate",
+                    value = "The end date.",
+                    required = false)
+                    Timestamp endDate,
+            @ApiParam(
+                    name = "generateBill",
+                    value = "The generate bill boolean.",
+                    required = false)
+                    boolean generateBill);
+
     @GET
     @Produces(MediaType.APPLICATION_JSON)
     @ApiOperation(

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/DeviceManagementServiceImpl.java

@@ -124,24 +124,12 @@ import org.wso2.carbon.utils.multitenancy.MultitenantUtils;
 
 import javax.validation.Valid;
 import javax.validation.constraints.Size;
-import javax.ws.rs.DELETE;
+import javax.ws.rs.*;
-import javax.ws.rs.GET;
-import javax.ws.rs.HeaderParam;
-import javax.ws.rs.POST;
-import javax.ws.rs.PUT;
-import javax.ws.rs.Path;
-import javax.ws.rs.PathParam;
-import javax.ws.rs.QueryParam;
-import javax.ws.rs.DefaultValue;
 import javax.ws.rs.core.Response;
 import java.sql.Timestamp;
-import java.text.DateFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
-import java.util.Date;
+import java.util.*;
-import java.util.List;
-import java.util.ArrayList;
-import java.util.Properties;
 
 @Path("/devices")
 public class DeviceManagementServiceImpl implements DeviceManagementService {
@@ -385,11 +373,12 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
             }
 
             devices.setList((List<Device>) result.getData());
+            devices.setBilledDateIsValid(result.isBilledDateIsValid());
+            devices.setMessage(result.getMessage());
             devices.setCount(result.getRecordsTotal());
             devices.setTotalCost(result.getTotalCost());
             return Response.status(Response.Status.OK).entity(devices).build();
-        }
+        } catch (Exception e) {
-        catch (Exception e) {
             String msg = "Error occurred while retrieving billing data";
             log.error(msg, e);
             return Response.serverError().entity(
@@ -397,6 +386,51 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
         }
     }
 
+    @GET
+    @Override
+    @Path("/billing/file")
+    public Response exportBilling(
+            @QueryParam("tenantDomain") String tenantDomain,
+            @QueryParam("startDate") Timestamp startDate,
+            @QueryParam("endDate") Timestamp endDate,
+            @QueryParam("generateBill") boolean generateBill) {
+
+        try {
+            DeviceManagementProviderService dms = DeviceMgtAPIUtils.getDeviceManagementService();
+            PaginationResult result;
+            int tenantId = 0;
+            RealmService realmService = DeviceMgtAPIUtils.getRealmService();
+            DeviceList devices = new DeviceList();
+
+            if (!tenantDomain.isEmpty()) {
+                tenantId = realmService.getTenantManager().getTenantId(tenantDomain);
+            } else {
+                tenantId = CarbonContext.getThreadLocalCarbonContext().getTenantId();
+            }
+
+            try {
+                result = dms.createBillingFile(tenantId, tenantDomain, startDate, endDate, generateBill);
+
+            } catch (Exception exception) {
+                String msg = "Error occurred when trying to retrieve billing data without pagination";
+                log.error(msg, exception);
+                return null;
+            }
+
+            devices.setList((List<Device>) result.getData());
+            devices.setBilledDateIsValid(result.isBilledDateIsValid());
+            devices.setMessage(result.getMessage());
+            devices.setCount(result.getRecordsTotal());
+            devices.setTotalCost(result.getTotalCost());
+            return Response.status(Response.Status.OK).entity(devices).build();
+        } catch (Exception e) {
+            String msg = "Error occurred while retrieving billing data without pagination";
+            log.error(msg, e);
+            return null;
+        }
+
+    }
+
     @GET
     @Override
     @Path("/user-devices")
@@ -1563,7 +1597,8 @@ public class DeviceManagementServiceImpl implements DeviceManagementService {
             String msg = "Error occurred when updating the application subscription status of the operation. " +
                     "The device identifier is: " + deviceIdentifier;
             log.error(msg, e);
-            return Response.status(Response.Status.INTERNAL_SERVER_ERROR).entity(msg).build();        }
+            return Response.status(Response.Status.INTERNAL_SERVER_ERROR).entity(msg).build();
+        }
     }
 
     @GET

components/device-mgt/org.wso2.carbon.device.mgt.common/src/main/java/org/wso2/carbon/device/mgt/common/Billing.java

@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2014, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
+ *
+ * WSO2 Inc. licenses this file to you under the Apache License,
+ * Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License.
+ * you may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.wso2.carbon.device.mgt.common;
+
+import com.google.gson.Gson;
+import io.swagger.annotations.ApiModel;
+import io.swagger.annotations.ApiModelProperty;
+import java.io.Serializable;
+
+@ApiModel(value = "Billing", description = "This class carries all information related to a device billing.")
+public class Billing implements Serializable {
+
+    private static final long serialVersionUID = 1998101711L;
+
+    @ApiModelProperty(name = "invoiceId", value = "ID of the billing.",
+            required = false)
+    private int invoiceId;
+
+    @ApiModelProperty(name = "deviceId", value = "Device id of the billing.",
+            required = false)
+    private int deviceId;
+
+    @ApiModelProperty(name = "tenantId", value = "Tenant of the device.",
+            required = false)
+    private int tenantId;
+
+    @ApiModelProperty(name = "billingStart", value = "Start date of the billing period.", required = false)
+    private Long billingStart;
+
+    @ApiModelProperty(name = "billingEnd", value = "End date of the billing period.", required = false)
+    private Long billingEnd;
+
+    @ApiModelProperty(name = "deviceCount", value = "Device count for a billing period",
+            required = false)
+    private int deviceCount;
+
+
+    public Billing() {
+    }
+
+    public Billing(int invoiceId, int deviceId, int tenantId, Long billingStart, Long billingEnd) {
+        this.invoiceId = invoiceId;
+        this.deviceId = deviceId;
+        this.tenantId = tenantId;
+        this.billingStart = billingStart;
+        this.billingEnd = billingEnd;
+    }
+
+    public int getInvoiceId() {
+        return invoiceId;
+    }
+
+    public void setInvoiceId(int invoiceId) {
+        this.invoiceId = invoiceId;
+    }
+
+    public int getDeviceId() {
+        return deviceId;
+    }
+
+    public void setDeviceId(int deviceId) {
+        this.deviceId = deviceId;
+    }
+
+    public int getTenantId() {
+        return tenantId;
+    }
+
+    public void setTenantId(int tenantId) {
+        this.tenantId = tenantId;
+    }
+
+    public Long getBillingStart() {
+        return billingStart;
+    }
+
+    public void setBillingStart(Long billingStart) {
+        this.billingStart = billingStart;
+    }
+
+    public Long getBillingEnd() {
+        return billingEnd;
+    }
+
+    public void setBillingEnd(Long billingEnd) {
+        this.billingEnd = billingEnd;
+    }
+
+    public int getDeviceCount() {
+        return deviceCount;
+    }
+
+    public void setDeviceCount(int deviceCount) {
+        this.deviceCount = deviceCount;
+    }
+
+    @Override
+    public String toString() {
+        return new Gson().toJson(this);
+    }
+
+
+}

components/device-mgt/org.wso2.carbon.device.mgt.common/src/main/java/org/wso2/carbon/device/mgt/common/PaginationResult.java

@@ -47,6 +47,28 @@ public class PaginationResult implements Serializable {
     @ApiModelProperty(name = "totalCost", value = "Total cost of all devices per tenant", required = false)
     private double totalCost;
 
+    @ApiModelProperty(name = "billedDateIsValid", value = "Check if user entered date is valid", required = false)
+    private boolean billedDateIsValid;
+
+    @ApiModelProperty(name = "message", value = "Send information text to the billing UI", required = false)
+    private String message;
+
+    public boolean isBilledDateIsValid() {
+        return billedDateIsValid;
+    }
+
+    public void setBilledDateIsValid(boolean billedDateIsValid) {
+        this.billedDateIsValid = billedDateIsValid;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+
     public double getTotalCost() {
         return totalCost;
     }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/DeviceManagementConstants.java

@@ -44,6 +44,7 @@ public final class DeviceManagementConstants {
     public static final String DEVICE_CACHE = "DEVICE_CACHE";
     public static final String API_RESOURCE_PERMISSION_CACHE = "API_RESOURCE_CACHE_CACHE";
     public static final String GEOFENCE_CACHE = "GEOFENCE_CACHE";
+    public static final String META_KEY = "PER_DEVICE_COST";
     public static final String ENROLLMENT_NOTIFICATION_API_ENDPOINT = "/api/device-mgt/enrollment-notification";
     public static final String URL_SEPERATOR = "/";
 

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/config/ui/Billing.java

@@ -7,6 +7,26 @@ public class Billing {
     private boolean isHideBillGenerationInSubTenant;
     private boolean isHideTotalCalculationInSuperTenant;
     private boolean isHideTotalCalculationInSubTenant;
+    private boolean isHideDomainSelectionInSuperTenant;
+    private boolean isHideDomainSelectionInSubTenant;
+
+    @XmlElement(name = "HideDomainSelectionInSuperTenant")
+    public boolean isHideDomainSelectionInSuperTenant() {
+        return isHideDomainSelectionInSuperTenant;
+    }
+
+    public void setHideDomainSelectionInSuperTenant(boolean hideDomainSelectionInSuperTenant) {
+        isHideDomainSelectionInSuperTenant = hideDomainSelectionInSuperTenant;
+    }
+
+    @XmlElement(name = "HideDomainSelectionInSubTenant")
+    public boolean isHideDomainSelectionInSubTenant() {
+        return isHideDomainSelectionInSubTenant;
+    }
+
+    public void setHideDomainSelectionInSubTenant(boolean hideDomainSelectionInSubTenant) {
+        isHideDomainSelectionInSubTenant = hideDomainSelectionInSubTenant;
+    }
 
     @XmlElement(name = "HideBillGenerationInSuperTenant")
     public boolean isHideBillGenerationInSuperTenant() {

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/BillingDAO.java

@@ -0,0 +1,13 @@
+package org.wso2.carbon.device.mgt.core.dao;
+
+import org.wso2.carbon.device.mgt.common.Billing;
+
+import java.sql.Timestamp;
+import java.util.List;
+
+public interface BillingDAO {
+
+    void addBilling(int deviceId, int tenantId, Timestamp billingStart, Timestamp billingEnd) throws DeviceManagementDAOException;
+
+    List<Billing> getBilling(int deviceId, Timestamp billingStart, Timestamp billingEnd) throws DeviceManagementDAOException;
+}

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/DeviceDAO.java

@@ -294,24 +294,12 @@ public interface DeviceDAO {
     List<Device> getDevices(PaginationRequest request, int tenantId) throws DeviceManagementDAOException;
 
     /**
-     * This method is used to retrieve the not removed devices of a given tenant as a paginated result.
+     * This method is used to retrieve the devices of a given tenant without pagination.
-     *
-     * @param request  PaginationRequest object holding the data for pagination
      * @param tenantId tenant id.
-     * @return returns paginated list of not removed devices of tenant.
+     * @return returns a list of devices of the tenant.
      * @throws DeviceManagementDAOException
      */
-    List<DeviceBilling> getDeviceBillList(PaginationRequest request, int tenantId, Timestamp startDate, Timestamp endDate) throws DeviceManagementDAOException;
+    List<Device> getDeviceListWithoutPagination(int tenantId) throws DeviceManagementDAOException;
-
-    /**
-     * This method is used to retrieve the removed devices of a given tenant as a paginated result.
-     *
-     * @param request  PaginationRequest object holding the data for pagination
-     * @param tenantId tenant id.
-     * @return rreturns paginated list of removed devices of tenant.
-     * @throws DeviceManagementDAOException
-     */
-    List<DeviceBilling> getRemovedDeviceBillList(PaginationRequest request, int tenantId) throws DeviceManagementDAOException;
 
     /**
      * This method is used to retrieve the devices of a given tenant as a paginated result, along the lines of

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/DeviceManagementDAOFactory.java

@@ -42,6 +42,7 @@ import org.wso2.carbon.device.mgt.core.privacy.dao.impl.PrivacyComplianceDAOImpl
 import javax.sql.DataSource;
 import java.sql.Connection;
 import java.sql.SQLException;
+import java.sql.Timestamp;
 import java.util.Hashtable;
 import java.util.List;
 
@@ -124,6 +125,11 @@ public class DeviceManagementDAOFactory {
     public static EnrollmentDAO getEnrollmentDAO() {
         return new EnrollmentDAOImpl();
     }
+
+    public static BillingDAO getBillingDAO() {
+        return new BillingDAOImpl();
+    }
+
     public static DeviceStatusDAO getDeviceStatusDAO() {
         return new DeviceStatusDAOImpl();
     }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/BillingDAOImpl.java

@@ -0,0 +1,71 @@
+package org.wso2.carbon.device.mgt.core.dao.impl;
+
+import org.wso2.carbon.device.mgt.common.Billing;
+import org.wso2.carbon.device.mgt.common.EnrolmentInfo;
+import org.wso2.carbon.device.mgt.core.dao.BillingDAO;
+import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOException;
+import org.wso2.carbon.device.mgt.core.dao.DeviceManagementDAOFactory;
+import org.wso2.carbon.device.mgt.core.dao.util.DeviceManagementDAOUtil;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class BillingDAOImpl implements BillingDAO {
+
+    @Override
+    public void addBilling(int deviceId, int tenantId, Timestamp billingStart, Timestamp billingEnd) throws DeviceManagementDAOException {
+
+        Connection conn;
+        PreparedStatement stmt = null;
+        ResultSet rs = null;
+        try {
+            conn = this.getConnection();
+            String sql = "INSERT INTO DM_BILLING(DEVICE_ID, TENANT_ID, BILLING_START, BILLING_END) VALUES(?, ?, ?, ?)";
+            stmt = conn.prepareStatement(sql, new String[] {"invoice_id"});
+            stmt.setInt(1, deviceId);
+            stmt.setInt(2,tenantId);
+            stmt.setTimestamp(3, billingStart);
+            stmt.setTimestamp(4, billingEnd);
+            stmt.execute();
+        } catch (SQLException e) {
+            e.printStackTrace();
+            throw new DeviceManagementDAOException("Error occurred while adding billing period", e);
+        } finally {
+            DeviceManagementDAOUtil.cleanupResources(stmt, rs);
+        }
+    }
+
+    @Override
+    public List<Billing> getBilling(int deviceId, Timestamp billingStart, Timestamp billingEnd) throws DeviceManagementDAOException {
+        List<Billing> billings = new ArrayList<>();
+        Connection conn;
+        PreparedStatement stmt = null;
+        ResultSet rs = null;
+        EnrolmentInfo.Status status = null;
+        try {
+            conn = this.getConnection();
+            String sql;
+
+            sql = "SELECT * FROM DM_BILLING WHERE DEVICE_ID = ?";
+            stmt = conn.prepareStatement(sql);
+            stmt.setInt(1, deviceId);
+            rs = stmt.executeQuery();
+
+            while (rs.next()) {
+                Billing bill = new Billing(rs.getInt("INVOICE_ID"), rs.getInt("DEVICE_ID"),rs.getInt("TENANT_ID"),
+                      (rs.getTimestamp("BILLING_START").getTime()), (rs.getTimestamp("BILLING_END").getTime()));
+                billings.add(bill);
+            }
+        } catch (SQLException e) {
+            throw new DeviceManagementDAOException("Error occurred getting billing periods", e);
+        } finally {
+            DeviceManagementDAOUtil.cleanupResources(stmt, null);
+        }
+        return billings;
+    }
+
+    private Connection getConnection() throws SQLException {
+        return DeviceManagementDAOFactory.getConnection();
+    }
+}

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/GenericDeviceDAOImpl.java

@@ -185,23 +185,23 @@ public class GenericDeviceDAOImpl extends AbstractDeviceDAOImpl {
     }
 
     @Override
-    public List<DeviceBilling> getDeviceBillList(PaginationRequest request, int tenantId, Timestamp startDate, Timestamp endDate)
+    public List<Device> getDeviceListWithoutPagination(int tenantId)
             throws DeviceManagementDAOException {
         Connection conn;
         PreparedStatement stmt = null;
-        List<DeviceBilling> devices = new ArrayList<>();
+        List<Device> devices = new ArrayList<>();
         try {
             conn = this.getConnection();
-            String sql = "SELECT DM_DEVICE.ID, DEVICE_IDENTIFICATION, DESCRIPTION, NAME AS DEVICE_NAME, DM_ENROLMENT.ID AS ENROLMENT_ID,\n" +
+            String sql = "SELECT DM_DEVICE.ID AS DEVICE_ID, DEVICE_IDENTIFICATION, DESCRIPTION, DM_DEVICE.NAME AS DEVICE_NAME, DM_DEVICE_TYPE.NAME AS DEVICE_TYPE,\n" +
-                    "    DATE_OF_ENROLMENT,STATUS, LAST_BILLED_DATE, TIMESTAMPDIFF('DAY', DATE_OF_ENROLMENT, CURDATE()) as DAYS_SINCE_ENROLLED\n" +
+                    "DM_ENROLMENT.ID AS ENROLMENT_ID, DATE_OF_ENROLMENT,OWNER, OWNERSHIP,IS_TRANSFERRED, STATUS, DATE_OF_LAST_UPDATE, LAST_BILLED_DATE,\n" +
-                    "    FROM DM_DEVICE JOIN DM_ENROLMENT ON (DM_DEVICE.ID = DM_ENROLMENT.DEVICE_ID)\n" +
+                    "TIMESTAMPDIFF('DAY', DATE_OF_ENROLMENT, CURDATE()) as DAYS_SINCE_ENROLLED FROM DM_DEVICE JOIN DM_ENROLMENT\n" +
-                    "    WHERE DM_ENROLMENT.TENANT_ID=?";
+                    "ON (DM_DEVICE.ID = DM_ENROLMENT.DEVICE_ID) JOIN DM_DEVICE_TYPE ON (DM_DEVICE.DEVICE_TYPE_ID = DM_DEVICE_TYPE.ID) WHERE DM_ENROLMENT.TENANT_ID=?";
             stmt = conn.prepareStatement(sql);
             stmt.setInt(1, tenantId);
             ResultSet rs = stmt.executeQuery();
 
             while (rs.next()) {
-                DeviceBilling device = DeviceManagementDAOUtil.loadDeviceBilling(rs);
+                Device device = DeviceManagementDAOUtil.loadDevice(rs);
                 devices.add(device);
             }
         } catch (SQLException e) {
@@ -212,35 +212,6 @@ public class GenericDeviceDAOImpl extends AbstractDeviceDAOImpl {
         return devices;
     }
 
-    @Override
-    public List<DeviceBilling> getRemovedDeviceBillList(PaginationRequest request, int tenantId)
-            throws DeviceManagementDAOException {
-        Connection conn;
-        PreparedStatement stmt = null;
-        List<DeviceBilling> devices = new ArrayList<>();
-        try {
-            conn = this.getConnection();
-            String sql = "select DEVICE_IDENTIFICATION, DESCRIPTION, NAME AS DEVICE_NAME, DATE_OF_ENROLMENT, LAST_BILLED_DATE, DATE_OF_LAST_UPDATE, STATUS, " +
-                    "TIMESTAMPDIFF('DAY', DATE_OF_ENROLMENT, DATE_OF_LAST_UPDATE) AS DAYS_USED from DM_DEVICE d, DM_ENROLMENT e" +
-                    " where e.TENANT_ID=? and d.ID=e.DEVICE_ID and STATUS ='REMOVED'\n";
-            stmt = conn.prepareStatement(sql);
-            stmt.setInt(1, tenantId);
-            ResultSet rs = stmt.executeQuery();
-
-            while (rs.next()) {
-//                DeviceBilling device = DeviceManagementDAOUtil.loadDeviceBilling(rs, true);
-                DeviceBilling device = DeviceManagementDAOUtil.loadDeviceBilling(rs);
-                devices.add(device);
-            }
-        } catch (SQLException e) {
-            throw new DeviceManagementDAOException("Error occurred while fetching the list of devices belongs to '" +
-                    request.getOwner() + "'", e);
-        } finally {
-            DeviceManagementDAOUtil.cleanupResources(stmt, null);
-        }
-        return devices;
-    }
-
     @Override
     public List<Device> getAllocatedDevices(PaginationRequest request, int tenantId, int activeServerCount, int serverIndex)
             throws DeviceManagementDAOException {

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/OracleDeviceDAOImpl.java

@@ -189,12 +189,7 @@ public class OracleDeviceDAOImpl extends AbstractDeviceDAOImpl {
     }
 
     @Override
-    public List<DeviceBilling> getRemovedDeviceBillList(PaginationRequest request, int tenantId) throws DeviceManagementDAOException {
+    public List<Device> getDeviceListWithoutPagination(int tenantId) throws DeviceManagementDAOException {
-        return null;
-    }
-
-    @Override
-    public List<DeviceBilling> getDeviceBillList(PaginationRequest request, int tenantId , Timestamp startDate, Timestamp endDate) throws DeviceManagementDAOException {
         return null;
     }
 

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/PostgreSQLDeviceDAOImpl.java

@@ -180,12 +180,7 @@ public class PostgreSQLDeviceDAOImpl extends AbstractDeviceDAOImpl {
     }
 
     @Override
-    public List<DeviceBilling> getRemovedDeviceBillList(PaginationRequest request, int tenantId) throws DeviceManagementDAOException {
+    public List<Device> getDeviceListWithoutPagination(int tenantId) throws DeviceManagementDAOException {
-        return null;
-    }
-
-    @Override
-    public List<DeviceBilling> getDeviceBillList(PaginationRequest request, int tenantId, Timestamp startDate, Timestamp endDate) throws DeviceManagementDAOException {
         return null;
     }
 

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/dao/impl/device/SQLServerDeviceDAOImpl.java

@@ -190,12 +190,7 @@ public class SQLServerDeviceDAOImpl extends AbstractDeviceDAOImpl {
     }
 
     @Override
-    public List<DeviceBilling> getRemovedDeviceBillList(PaginationRequest request, int tenantId) throws DeviceManagementDAOException {
+    public List<Device> getDeviceListWithoutPagination(int tenantId) throws DeviceManagementDAOException {
-        return null;
-    }
-
-    @Override
-    public List<DeviceBilling> getDeviceBillList(PaginationRequest request, int tenantId, Timestamp startDate, Timestamp endDate) throws DeviceManagementDAOException {
         return null;
     }
 

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/service/DeviceManagementProviderService.java

@@ -209,6 +209,17 @@ public interface DeviceManagementProviderService {
      */
     PaginationResult getAllDevicesBillings(PaginationRequest request, int tenantId, String tenantDomain, Timestamp startDate, Timestamp endDate, boolean generateBill) throws DeviceManagementException;
 
+    /**
+     * Method to retrieve all the devices with pagination support.
+     *
+     * @return PaginationResult - Result including the device bill list without pagination.
+     * @throws DeviceManagementException If some unusual behaviour is observed while fetching billing of
+     *                                   devices.
+     */
+    PaginationResult createBillingFile(int tenantId, String tenantDomain, Timestamp startDate, Timestamp endDate, boolean generateBill) throws DeviceManagementException;
+
+
+
     /**
      * Returns the device of specified id.
      *

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/service/DeviceManagementProviderServiceImpl.java

@@ -138,6 +138,8 @@ import java.io.StringWriter;
 import java.lang.reflect.Type;
 import java.sql.SQLException;
 import java.sql.Timestamp;
+import java.text.Format;
+import java.text.SimpleDateFormat;
 import java.util.*;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
@@ -156,6 +158,7 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
     private final EnrollmentDAO enrollmentDAO;
     private final ApplicationDAO applicationDAO;
     private MetadataDAO metadataDAO;
+    private final BillingDAO billingDAO;
     private final DeviceStatusDAO deviceStatusDAO;
 
     public DeviceManagementProviderServiceImpl() {
@@ -165,6 +168,7 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
         this.deviceTypeDAO = DeviceManagementDAOFactory.getDeviceTypeDAO();
         this.enrollmentDAO = DeviceManagementDAOFactory.getEnrollmentDAO();
         this.metadataDAO = MetadataManagementDAOFactory.getMetadataDAO();
+        this.billingDAO = DeviceManagementDAOFactory.getBillingDAO();
         this.deviceStatusDAO = DeviceManagementDAOFactory.getDeviceStatusDAO();
 
         /* Registering a listener to retrieve events when some device management service plugin is installed after
@@ -937,6 +941,183 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
         return this.getAllDevices(request, true);
     }
 
+    public PaginationResult calculateCost(int tenantId, String tenantDomain, Timestamp startDate, Timestamp endDate, boolean generateBill, List<Device> allDevices) throws DeviceManagementException {
+
+        PaginationResult paginationResult = new PaginationResult();
+        double totalCost = 0.0;
+        boolean allDevicesBilledDateIsValid = true;
+        String lastBilledDates = "";
+        ArrayList<String> lastBilledDatesList =  new ArrayList<>();
+        List<Billing> invalidDevices =  new ArrayList<>();
+        List<Device> removeBillingPeriodInvalidDevices =  new ArrayList<>() ;
+        List<Device> removeStatusUpdateInvalidDevices =  new ArrayList<>() ;
+
+        try {
+            MetadataManagementDAOFactory.beginTransaction();
+            Metadata metadata = metadataDAO.getMetadata(-1234, DeviceManagementConstants.META_KEY);
+
+            Gson g = new Gson();
+            Collection<Cost> costData = null;
+
+
+            Type collectionType = new TypeToken<Collection<Cost>>() {}.getType();
+            if (metadata != null) {
+                costData = g.fromJson(metadata.getMetaValue(), collectionType);
+                for (Cost tenantCost : costData) {
+                    if (tenantCost.getTenantDomain().equals(tenantDomain)) {
+                        for (Device device : allDevices) {
+                            device.setDeviceStatusInfo(getDeviceStatusHistory(device, null, null, true));
+                            long dateDiff = 0;
+
+                            List<DeviceStatus> deviceStatus = device.getDeviceStatusInfo();
+                            boolean lastBilledDate = false;
+                            boolean deviceStatusIsValid = false;
+
+                            List<Billing> deviceBilling = billingDAO.getBilling(device.getId(), startDate, endDate);
+                            boolean billDateIsInvalid = false;
+
+                            if (deviceBilling.isEmpty()) {
+                                billDateIsInvalid = false;
+                            }
+
+                            if (generateBill) {
+                                for (Billing bill : deviceBilling) {
+                                    if ((bill.getBillingStart() <= startDate.getTime() && startDate.getTime() <= bill.getBillingEnd()) ||
+                                            (bill.getBillingStart() <= endDate.getTime()  && endDate.getTime() <= bill.getBillingEnd())) {
+                                        billDateIsInvalid = true;
+                                        invalidDevices.add(bill);
+                                    }
+                                }
+                            }
+
+                            if (!billDateIsInvalid) {
+                                for (int i = 0; i < deviceStatus.size(); i++) {
+                                    if (deviceStatus.get(i).getStatus().toString().equals("ACTIVE")) {
+                                        if (deviceStatus.size() > i + 1) {
+                                            if (!lastBilledDate) {
+                                                lastBilledDate = true;
+                                                if (device.getEnrolmentInfo().getLastBilledDate() == 0) {
+                                                    deviceStatusIsValid = true;
+                                                    dateDiff = dateDiff + (deviceStatus.get(i + 1).getUpdateTime().getTime() - deviceStatus.get(i).getUpdateTime().getTime());
+                                                } else {
+                                                    if (deviceStatus.get(i + 1).getUpdateTime().getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
+                                                        deviceStatusIsValid = true;
+                                                        dateDiff = dateDiff + (deviceStatus.get(i + 1).getUpdateTime().getTime() - device.getEnrolmentInfo().getLastBilledDate());
+                                                    }
+                                                }
+                                            } else {
+                                                if (deviceStatus.get(i).getUpdateTime().getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
+                                                    deviceStatusIsValid = true;
+                                                    dateDiff = dateDiff + (deviceStatus.get(i + 1).getUpdateTime().getTime() - deviceStatus.get(i).getUpdateTime().getTime());
+                                                }
+                                            }
+                                        } else {   // The last status update calculation is done in this block
+                                            // If only one status row is retrieved this block is executed
+                                            if (!lastBilledDate) {
+                                                lastBilledDate = true;
+                                                // Is executed if there is no lastBilled date and if the updates time is before the enddate
+                                                if (device.getEnrolmentInfo().getLastBilledDate() == 0) {
+                                                    if (endDate.getTime() >= deviceStatus.get(i).getUpdateTime().getTime()) {
+                                                        deviceStatusIsValid = true;
+                                                        dateDiff = dateDiff + (endDate.getTime() - deviceStatus.get(i).getUpdateTime().getTime());
+                                                    }
+                                                } else {
+                                                    if (endDate.getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
+                                                        deviceStatusIsValid = true;
+                                                        dateDiff = dateDiff + (endDate.getTime() - device.getEnrolmentInfo().getLastBilledDate());
+                                                    }
+                                                }
+                                            } else {
+                                                if (device.getEnrolmentInfo().getLastBilledDate() <= deviceStatus.get(i).getUpdateTime().getTime()
+                                                        && endDate.getTime() >= deviceStatus.get(i).getUpdateTime().getTime()) {
+                                                    deviceStatusIsValid = true;
+                                                    dateDiff = dateDiff + (endDate.getTime() - deviceStatus.get(i).getUpdateTime().getTime());
+                                                }
+                                                if (device.getEnrolmentInfo().getLastBilledDate() >= deviceStatus.get(i).getUpdateTime().getTime()
+                                                        && endDate.getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
+                                                    deviceStatusIsValid = true;
+                                                    dateDiff = dateDiff + (endDate.getTime() - device.getEnrolmentInfo().getLastBilledDate());
+                                                }
+                                            }
+                                        }
+                                    }
+                                }
+
+                                long dateInDays = TimeUnit.DAYS.convert(dateDiff, TimeUnit.MILLISECONDS);
+                                double cost = (tenantCost.getCost() / 365) * dateInDays;
+                                totalCost = cost + totalCost;
+                                device.setCost(Math.round(cost * 100.0) / 100.0);
+                                device.setDaysUsed((int) dateInDays);
+
+                                if (generateBill) {
+                                    enrollmentDAO.updateEnrollmentLastBilledDate(device.getEnrolmentInfo(), endDate, tenantId);
+                                    billingDAO.addBilling(device.getId(), tenantId, startDate, endDate);
+                                    DeviceManagementDAOFactory.commitTransaction();
+                                }
+
+                            } else {
+
+                                for (int i = 0; i < deviceStatus.size(); i++) {
+                                    if (endDate.getTime() >= deviceStatus.get(i).getUpdateTime().getTime()
+                                            && startDate.getTime() <= deviceStatus.get(i).getUpdateTime().getTime()) {
+                                        deviceStatusIsValid = true;
+                                    }
+                                }
+                                if (device.getEnrolmentInfo().getLastBilledDate() != 0) {
+                                    Date date = new Date(device.getEnrolmentInfo().getLastBilledDate());
+                                    Format format = new SimpleDateFormat("yyyy MM dd");
+                                    if (!lastBilledDatesList.contains(lastBilledDatesList.add(format.format(date)))) {
+                                        lastBilledDatesList.add(format.format(date));
+                                    }
+
+                                    lastBilledDates =  lastBilledDates + ' ' + lastBilledDatesList;
+                                }
+                                removeBillingPeriodInvalidDevices.add(device);
+                            }
+
+                            if (!deviceStatusIsValid) {
+                                removeStatusUpdateInvalidDevices.add(device);
+                            }
+                        }
+
+                    }
+                }
+            }
+        } catch (DeviceManagementDAOException e) {
+            String msg = "Error occurred while retrieving device list pertaining to the current tenant";
+            log.error(msg, e);
+            throw new DeviceManagementException(msg, e);
+        } catch (Exception e) {
+            String msg = "Error occurred in getAllDevices";
+            log.error(msg, e);
+            throw new DeviceManagementException(msg, e);
+        } finally {
+            DeviceManagementDAOFactory.closeConnection();
+            MetadataManagementDAOFactory.closeConnection();
+        }
+
+        if(!removeBillingPeriodInvalidDevices.isEmpty() && removeBillingPeriodInvalidDevices.size() == allDevices.size()) {
+            allDevicesBilledDateIsValid = false;
+            paginationResult.setMessage("Invalid bill period last billed dates of devices are " +lastBilledDates);
+        }
+        if(!removeStatusUpdateInvalidDevices.isEmpty() && removeStatusUpdateInvalidDevices.size() == allDevices.size()) {
+            allDevicesBilledDateIsValid = false;
+            if (paginationResult.getMessage() != null){
+                paginationResult.setMessage(paginationResult.getMessage() + " and no device updates within entered bill period.");
+            } else {
+                paginationResult.setMessage("Devices have not been updated within the given period or entered end date comes before the last billed date");
+            }
+
+        }
+        allDevices.removeAll(removeBillingPeriodInvalidDevices);
+        allDevices.removeAll(removeStatusUpdateInvalidDevices);
+
+        paginationResult.setBilledDateIsValid(allDevicesBilledDateIsValid);
+        paginationResult.setData(allDevices);
+        paginationResult.setTotalCost(Math.round(totalCost * 100.0) / 100.0);
+        return paginationResult;
+    }
+
     @Override
     public PaginationResult getAllDevicesBillings(PaginationRequest request, int tenantId, String tenantDomain, Timestamp startDate, Timestamp endDate, boolean generateBill) throws DeviceManagementException {
         if (request == null) {
@@ -947,105 +1128,50 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
 
         DeviceManagerUtil.validateDeviceListPageSize(request);
         PaginationResult paginationResult = new PaginationResult();
-        double totalCost = 0.0;
         List<Device> allDevices;
         int count = 0;
 
         try {
             DeviceManagementDAOFactory.beginTransaction();
-//            allDevices = deviceDAO.getDeviceBillList(request, tenantId, startDate, endDate);
             allDevices = deviceDAO.getDevices(request, tenantId);
             count = deviceDAO.getDeviceCount(request, tenantId);
-
+            paginationResult = calculateCost(tenantId, tenantDomain, startDate, endDate, generateBill, allDevices);
-            String metaKey = "PER_DEVICE_COST";
-            MetadataManagementDAOFactory.beginTransaction();
-            Metadata metadata = metadataDAO.getMetadata(tenantId, metaKey);
-
-            Gson g = new Gson();
-            Collection<Cost> costData = null;
-
-            Type collectionType = new TypeToken<Collection<Cost>>(){}.getType();
-            if (metadata != null) {
-                costData = g.fromJson(metadata.getMetaValue(), collectionType);
-                for (Cost tenantCost: costData) {
-                    if (tenantCost.getTenantDomain().equals(tenantDomain)) {
-                        for (Device device: allDevices) {
-                            device.setDeviceStatusInfo(getDeviceStatusHistory(device, startDate, endDate, true));
-                            long dateDiff = 0;
-
-                            List<DeviceStatus> deviceStatus = device.getDeviceStatusInfo();
-                            boolean lastBilledDate = false;
-
-                            for (int i=0; i<deviceStatus.size(); i++) {
-                                if(deviceStatus.get(i).getStatus().toString().equals("ACTIVE")) {
-                                    if (deviceStatus.size()> i+1) {
-                                        if (!lastBilledDate) {
-                                            lastBilledDate = true;
-                                            if (device.getEnrolmentInfo().getLastBilledDate() == 0) {
-                                                dateDiff = dateDiff + (deviceStatus.get(i+1).getUpdateTime().getTime() - deviceStatus.get(i).getUpdateTime().getTime());
-                                            } else {
-                                                if (deviceStatus.get(i+1).getUpdateTime().getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
-                                                    dateDiff = dateDiff + (deviceStatus.get(i+1).getUpdateTime().getTime() - device.getEnrolmentInfo().getLastBilledDate());
-                                                }
-                                            }
-                                        } else {
-                                            if ( deviceStatus.get(i).getUpdateTime().getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
-                                                dateDiff = dateDiff + (deviceStatus.get(i+1).getUpdateTime().getTime() - deviceStatus.get(i).getUpdateTime().getTime());
-                                            }
-                                        }
-                                    } else {
-                                        if (!lastBilledDate) {
-                                            lastBilledDate = true;
-                                            if (device.getEnrolmentInfo().getLastBilledDate() == 0) {
-                                                dateDiff = dateDiff + (endDate.getTime() - deviceStatus.get(i).getUpdateTime().getTime());
-                                            } else {
-                                                if (endDate.getTime() >= device.getEnrolmentInfo().getLastBilledDate()) {
-                                                    dateDiff = dateDiff +(endDate.getTime() - device.getEnrolmentInfo().getLastBilledDate());
-                                                }
-                                            }
-                                        } else {
-                                            dateDiff = dateDiff + (endDate.getTime() - deviceStatus.get(i).getUpdateTime().getTime());
-                                        }
-                                    }
-                                }
-                            }
-
-                            long dateInDays = TimeUnit.DAYS.convert(dateDiff, TimeUnit.MILLISECONDS);;
-                            double cost = (tenantCost.getCost()/365)*dateInDays;
-                            totalCost = cost + totalCost;
-                            device.setCost(Math.round(cost * 100.0) / 100.0);
-                            device.setDaysUsed((int) dateInDays);
-
-                            if (generateBill) {
-                                Timestamp timestamp = new Timestamp(System.currentTimeMillis());
-                                enrollmentDAO.updateEnrollmentLastBilledDate(device.getEnrolmentInfo(), timestamp, tenantId);
-                            }
-
-                        }
-                    }
-                }
-            }
 
         } catch (DeviceManagementDAOException e) {
-            String msg = "Error occurred while retrieving device list pertaining to the current tenant";
+            String msg = "Error occurred while retrieving device bill list pertaining to the current tenant";
+            log.error(msg, e);
+            throw new DeviceManagementException(msg, e);
+        } catch (Exception e) {
+            String msg = "Error occurred in getAllDevicesBillings";
             log.error(msg, e);
             throw new DeviceManagementException(msg, e);
         }
-        catch (Exception e) {
-            String msg = "Error occurred in getAllDevices";
-            log.error(msg, e);
-            throw new DeviceManagementException(msg, e);
-        } finally {
-            DeviceManagementDAOFactory.closeConnection();
-            MetadataManagementDAOFactory.closeConnection();
-        }
-        paginationResult.setData(allDevices);
-        paginationResult.setTotalCost(Math.round(totalCost * 100.0) / 100.0);
         paginationResult.setRecordsFiltered(count);
         paginationResult.setRecordsTotal(count);
         return paginationResult;
     }
 
+    @Override
+    public PaginationResult createBillingFile(int tenantId, String tenantDomain, Timestamp startDate, Timestamp endDate, boolean generateBill) throws DeviceManagementException {
+        PaginationResult paginationResult = new PaginationResult();
+        List<Device> allDevices;
+        try {
+            DeviceManagementDAOFactory.beginTransaction();
+            allDevices = deviceDAO.getDeviceListWithoutPagination(tenantId);
+            paginationResult = calculateCost(tenantId, tenantDomain, startDate, endDate, generateBill, allDevices);
+
+        } catch (DeviceManagementDAOException e) {
+            String msg = "Error occurred while retrieving device bill list without pagination pertaining to the current tenant";
+            log.error(msg, e);
+            throw new DeviceManagementException(msg, e);
+        } catch (Exception e) {
+            String msg = "Error occurred in createBillingFile";
+            log.error(msg, e);
+            throw new DeviceManagementException(msg, e);
+        }
+        return paginationResult;
+    }
+
     @Override
     public PaginationResult getAllDevices(PaginationRequest request, boolean requireDeviceInfo) throws DeviceManagementException {
         if (request == null) {
@@ -1862,6 +1988,7 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
             DeviceManagementDAOFactory.closeConnection();
         }
     }
+
     @Override
     public List<DeviceStatus> getDeviceStatusHistory(Device device, Date fromDate, Date toDate, boolean billingStatus) throws DeviceManagementException {
         if (log.isDebugEnabled()) {