org.demoiselle.jee.crud.pagination.PaginationHelper Maven / Gradle / Ivy
/*
* Demoiselle Framework
*
* License: GNU Lesser General Public License (LGPL), version 3 or later.
* See the lgpl.txt file in the root directory or .
*/
package org.demoiselle.jee.crud.pagination;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.logging.Logger;
import javax.enterprise.context.RequestScoped;
import javax.inject.Inject;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ResourceInfo;
import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.UriInfo;
import org.demoiselle.jee.crud.AbstractDAO;
import org.demoiselle.jee.crud.CrudUtilHelper;
import org.demoiselle.jee.crud.DemoiselleRequestContext;
import org.demoiselle.jee.crud.ReservedHTTPHeaders;
import org.demoiselle.jee.crud.ReservedKeyWords;
import org.demoiselle.jee.crud.Search;
/**
* Class responsible for managing the 'range' parameter comes from Url Query String.
*
* Ex:
*
* Given a request
*
* GET @{literal http://localhost:8080/api/users?range=0-10}
*
*
* This class will processing the request above and parse the range parameters to
* {@link DemoiselleRequestContext} object.
*
* This object will be use on {@link AbstractDAO} class to execute the pagination on database.
*
*/
@RequestScoped
public class PaginationHelper {
private UriInfo uriInfo;
private ResourceInfo resourceInfo;
@Inject
private DemoiselleRequestContext drc;
@Inject
private PaginationHelperMessage message;
@Inject
private PaginationHelperConfig paginationConfig;
private static final Logger logger = Logger.getLogger(PaginationHelper.class.getName());
public PaginationHelper() {
}
public PaginationHelper(ResourceInfo resourceInfo, UriInfo uriInfo, PaginationHelperConfig paginationConfig, DemoiselleRequestContext drc, PaginationHelperMessage message) {
this.resourceInfo = resourceInfo;
this.uriInfo = uriInfo;
this.paginationConfig = paginationConfig;
this.drc = drc;
this.message = message;
}
/**
* Open the request query string to extract values from 'range' parameter and
* fill the {@link DemoiselleRequestContext#setOffset(Integer)} and {@link DemoiselleRequestContext#setLimit(Integer)}
*
* @param resourceInfo ResourceInfo
* @param uriInfo UriInfo
*/
public void execute(ResourceInfo resourceInfo, UriInfo uriInfo) {
fillObjects(resourceInfo, uriInfo);
drc.setPaginationEnabled(isPaginationEnabled());
if (drc.isPaginationEnabled()) {
if (isRequestPagination()) {
checkAndFillRangeValues();
}
if (hasSearchAnnotation() && !isRequestPagination()) {
drc.setLimit(getDefaultNumberPagination() - 1);
drc.setOffset(new Integer(0));
}
}
if (hasSearchAnnotation() && isRequestPagination()) {
Search searchAnnotation = resourceInfo.getResourceMethod().getAnnotation(Search.class);
// Pagination @Search.withPagination is disabled but the request parameter has 'range' parameter
if (searchAnnotation.withPagination() == Boolean.FALSE){
throw new IllegalArgumentException(message.paginationIsNotEnabled());
}
}
}
private void fillObjects(ResourceInfo resourceInfo, UriInfo uriInfo) {
this.resourceInfo = resourceInfo == null ? this.resourceInfo : resourceInfo;
this.uriInfo = uriInfo == null ? this.uriInfo : uriInfo;
}
/**
* Check the pagination is enabled
*
* @return pagination enabled/disabled
*/
private Boolean isPaginationEnabled() {
if (paginationConfig.getIsGlobalEnabled() == Boolean.FALSE) {
return Boolean.FALSE;
}
if (hasSearchAnnotation()) {
Search searchAnnotation = resourceInfo.getResourceMethod().getAnnotation(Search.class);
return searchAnnotation.withPagination();
}
return paginationConfig.getIsGlobalEnabled();
}
/**
* Check if the actual request has the 'range' parameter on query string
*
* @return is request pagination or not
*/
private Boolean isRequestPagination() {
// Verify if contains 'range' in url
if (uriInfo.getQueryParameters().containsKey(ReservedKeyWords.DEFAULT_RANGE_KEY.getKey())) {
return Boolean.TRUE;
}
return Boolean.FALSE;
}
/**
* Check if the value of 'range' parameter is valid using the rules:
*
* - Value formatted like offset-limit (range=0-10);
* - The 'offset' and 'limit' should be a integer;
* - The 'offset' should be less than or equals 'limit';
*
*
* @throws IllegalArgumentException The format is invalid
*/
private void checkAndFillRangeValues() throws IllegalArgumentException {
List rangeList = uriInfo.getQueryParameters().get(ReservedKeyWords.DEFAULT_RANGE_KEY.getKey());
if (!rangeList.isEmpty()) {
String range[] = rangeList.get(0).split("-");
if (range.length == 2) {
String offset = range[0];
String limit = range[1];
try {
drc.setOffset(new Integer(offset));
drc.setLimit(new Integer(limit));
if (drc.getOffset() > drc.getLimit()) {
logInvalidRangeParameters(rangeList.get(0));
throw new IllegalArgumentException(this.message.invalidRangeParameters());
}
if (((drc.getLimit() - drc.getOffset()) + 1) > getDefaultNumberPagination()) {
logger.warning(message.defaultPaginationNumberExceed(getDefaultNumberPagination()) + ", [" + drc.toString() + "]");
throw new IllegalArgumentException(message.defaultPaginationNumberExceed(getDefaultNumberPagination()));
}
}
catch (NumberFormatException nfe) {
logInvalidRangeParameters(rangeList.get(0));
throw new IllegalArgumentException(message.invalidRangeParameters());
}
}
else {
logInvalidRangeParameters(rangeList.get(0));
throw new IllegalArgumentException(message.invalidRangeParameters());
}
}
}
/**
* Get default pagination number, if the target method is annotated with Search annotation the default annotation
* will be {@link Search#quantityPerPage()} otherwise the default pagination will be {@link PaginationHelperConfig#getDefaultPagination()} value;
*
* @return Number per page
*/
private Integer getDefaultNumberPagination() {
if (hasSearchAnnotation()) {
Search searchAnnotation = resourceInfo.getResourceMethod().getAnnotation(Search.class);
return searchAnnotation.quantityPerPage();
}
return paginationConfig.getDefaultPagination();
}
private Boolean hasSearchAnnotation() {
return resourceInfo.getResourceMethod().isAnnotationPresent(Search.class);
}
/**
* Check if the actual response is a Partial Content (HTTP 206 code)
* @return is partial content or not
*/
public Boolean isPartialContentResponse() {
Integer limit = drc.getLimit() == null ? 0 : drc.getLimit();
Long count = drc.getCount() == null ? 0 : drc.getCount();
return !((limit + 1) >= count);
}
private void logInvalidRangeParameters(String range) {
logger.warning(message.invalidRangeParameters() + ", [params: " + range + "]");
}
/**
* Build the 'Content-Range' HTTP Header value.
*
* @return 'Content-Range' value
*/
private String buildContentRange() {
Integer limit = drc.getLimit() == null ? getDefaultNumberPagination() - 1 : drc.getLimit();
Integer offset = drc.getOffset() == null ? 0 : drc.getOffset();
Long count = drc.getCount() == null ? 0 : drc.getCount();
return offset + "-" + (limit.equals(0) ? count - 1 : limit) + "/" + count;
}
/**
* Build the 'Accept-Range' HTTP Header value.
*
* @return 'Accept-Range' value
*/
public String buildAcceptRange() {
String resource = "";
if (drc.getEntityClass() != null) {
resource = drc.getEntityClass().getSimpleName().toLowerCase();
}
else {
if (resourceInfo != null && resourceInfo.getResourceClass() != null) {
Class targetClass = CrudUtilHelper.getTargetClass(resourceInfo.getResourceClass());
if (targetClass != null) {
resource = targetClass.getSimpleName().toLowerCase();
}
}
}
if(!resource.isEmpty()){
return resource + " " + getDefaultNumberPagination();
}
return null;
}
/**
* Set the 'Content-Range', 'Accept-Range', 'Link' and 'Access-Control-Expose-Headers' HTTP headers;
*
* @param resourceInfo ResourceInfo
* @param uriInfo UriInfo
*
* @return A map with HTTP headers
*/
public Map buildHeaders(ResourceInfo resourceInfo, UriInfo uriInfo) {
fillObjects(resourceInfo, uriInfo);
Map headers = new ConcurrentHashMap<>();
if (drc.isPaginationEnabled()) {
headers.put(ReservedHTTPHeaders.HTTP_HEADER_CONTENT_RANGE.getKey(), buildContentRange());
headers.put(ReservedHTTPHeaders.HTTP_HEADER_ACCEPT_RANGE.getKey(), buildAcceptRange());
String linkHeader = buildLinkHeader();
if (!linkHeader.isEmpty()) {
headers.put(HttpHeaders.LINK, linkHeader);
}
}
return headers;
}
/**
* Build the 'Link' HTTP header value
*
* @return 'Link' value
*/
private String buildLinkHeader() {
StringBuffer sb = new StringBuffer();
String url = uriInfo.getRequestUri().toString();
url = url.replaceFirst(".range=([^&]*)", "");
if (drc.getOffset() == null){
drc.setOffset(new Integer(0));
}
if (drc.getLimit() == null){
drc.setLimit(getDefaultNumberPagination() - 1);
}
Integer offset = drc.getOffset() + 1;
Integer limit = drc.getLimit() + 1;
Integer quantityPerPage = (limit - offset) + 1;
if (uriInfo.getQueryParameters().isEmpty()
|| (uriInfo.getQueryParameters().size() == 1 && uriInfo.getQueryParameters().containsKey(ReservedKeyWords.DEFAULT_RANGE_KEY.getKey()))) {
url += "?" + ReservedKeyWords.DEFAULT_RANGE_KEY.getKey() + "=";
} else {
url += "&" + ReservedKeyWords.DEFAULT_RANGE_KEY.getKey() + "=";
}
if (!isFirstPage()) {
Integer prevPageRangeInit = (drc.getOffset() - quantityPerPage) < 0 ? 0 : (drc.getOffset() - quantityPerPage);
Integer firstRange2 = quantityPerPage - 1 < drc.getOffset() - 1 ? quantityPerPage - 1 : drc.getOffset() - 1;
String firstPage = url + 0 + "-" + firstRange2;
String prevPage = url + prevPageRangeInit + "-" + (drc.getOffset() - 1);
sb.append("<").append(firstPage).append(">; rel=\"first\",");
sb.append("<").append(prevPage).append(">; rel=\"prev\",");
}
if (isPartialContentResponse()) {
String nextPage = url + (drc.getOffset() + quantityPerPage) + "-" + (2 * quantityPerPage + drc.getOffset() - 1);
String lastPage = url + (drc.getCount() - quantityPerPage) + "-" + (drc.getCount() - 1);
if (offset + quantityPerPage >= drc.getCount() - 1) {
nextPage = lastPage;
}
sb.append("<").append(nextPage).append(">; rel=\"next\",");
sb.append("<").append(lastPage).append(">; rel=\"last\"");
}
return sb.toString();
}
private Boolean isFirstPage() {
return drc.getOffset().equals(0);
}
public void buildAcceptRangeWithResponse(ContainerResponseContext response) {
if (response != null) {
String acceptRangeHeader = buildAcceptRange();
if(acceptRangeHeader != null){
response.getHeaders().putSingle(ReservedHTTPHeaders.HTTP_HEADER_ACCEPT_RANGE.getKey(), acceptRangeHeader);
}
}
}
}