// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.io;
import static org.openstreetmap.josm.tools.I18n.tr;
import static org.openstreetmap.josm.tools.I18n.trn;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.logging.Logger;
import org.openstreetmap.josm.data.osm.DataSet;
import org.openstreetmap.josm.data.osm.DataSetMerger;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
import org.openstreetmap.josm.data.osm.PrimitiveId;
import org.openstreetmap.josm.data.osm.Relation;
import org.openstreetmap.josm.data.osm.RelationMember;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.gui.progress.NullProgressMonitor;
import org.openstreetmap.josm.gui.progress.ProgressMonitor;
import org.openstreetmap.josm.tools.CheckParameterUtil;
/**
* Retrieves a set of {@see OsmPrimitive}s from an OSM server using the so called
* Multi Fetch API.
*
* Usage:
* <pre>
* MultiFetchServerObjectReader reader = MultiFetchServerObjectReader()
* .append(2345,2334,4444)
* .append(new Node(72343));
* reader.parseOsm();
* if (!reader.getMissingPrimitives().isEmpty()) {
* System.out.println("There are missing primitives: " + reader.getMissingPrimitives());
* }
* if (!reader.getSkippedWays().isEmpty()) {
* System.out.println("There are skipped ways: " + reader.getMissingPrimitives());
* }
* </pre>
*
*
*/
public class MultiFetchServerObjectReader extends OsmServerReader{
static private Logger logger = Logger.getLogger(MultiFetchServerObjectReader.class.getName());
/**
* the max. number of primitives retrieved in one step. Assuming IDs with 7 digits,
* this leads to a max. request URL of ~ 1600 Bytes ((7 digits + 1 Separator) * 200),
* which should be safe according to the
* <a href="http://www.boutell.com/newfaq/misc/urllength.html">WWW FAQ</a>.
*
*/
static private int MAX_IDS_PER_REQUEST = 200;
private HashSet<Long> nodes;
private HashSet<Long> ways;
private HashSet<Long> relations;
private HashSet<Long> missingPrimitives;
private DataSet outputDataSet;
/**
* constructor
*
*/
public MultiFetchServerObjectReader() {
nodes = new HashSet<Long>();
ways = new HashSet<Long>();
relations = new HashSet<Long>();
this.outputDataSet = new DataSet();
this.missingPrimitives = new HashSet<Long>();
}
/**
* Remembers an {@see OsmPrimitive}'s id. The id will
* later be fetched as part of a Multi Get request.
*
* Ignore the id if it represents a new primitives.
*
* @param id the id
*/
protected void remember(PrimitiveId id) {
if (id.isNew()) return;
switch(id.getType()) {
case NODE: nodes.add(id.getUniqueId()); break;
case WAY: ways.add(id.getUniqueId()); break;
case RELATION: relations.add(id.getUniqueId()); break;
}
}
/**
* remembers an {@see OsmPrimitive}'s id. <code>ds</code> must include
* an {@see OsmPrimitive} with id=<code>id</code>. The id will
* later we fetched as part of a Multi Get request.
*
* Ignore the id if it id <= 0.
*
* @param ds the dataset (must not be null)
* @param id the id
* @exception IllegalArgumentException thrown, if ds is null
* @exception NoSuchElementException thrown, if ds doesn't include an {@see OsmPrimitive} with
* id=<code>id</code>
*/
protected void remember(DataSet ds, long id, OsmPrimitiveType type) throws IllegalArgumentException, NoSuchElementException{
CheckParameterUtil.ensureParameterNotNull(ds, "ds");
if (id <= 0) return;
OsmPrimitive primitive = ds.getPrimitiveById(id, type);
if (primitive == null)
throw new NoSuchElementException(tr("No primitive with id {0} in local dataset. Cannot infer primitive type.", id));
remember(primitive.getPrimitiveId());
return;
}
/**
* appends a {@see Node}s id to the list of ids which will be fetched from the server.
*
* @param node the node (ignored, if null)
* @return this
*
*/
public MultiFetchServerObjectReader append(DataSet ds, long id, OsmPrimitiveType type) {
switch(type) {
case NODE:
Node n = (Node)ds.getPrimitiveById(id,type);
append(n);
break;
case WAY:
Way w= (Way)ds.getPrimitiveById(id,type);
append(w);
break;
case RELATION:
Relation r = (Relation)ds.getPrimitiveById(id,type);
append(r);
break;
}
return this;
}
/**
* appends a {@see Node}s id to the list of ids which will be fetched from the server.
*
* @param node the node (ignored, if null)
* @return this
*
*/
public MultiFetchServerObjectReader append(Node node) {
if (node == null) return this;
remember(node.getPrimitiveId());
return this;
}
/**
* appends a {@see Way}s id and the list of ids of nodes the way refers to the list of ids which will be fetched from the server.
*
* @param way the way (ignored, if null)
* @return this
*
*/
public MultiFetchServerObjectReader append(Way way) {
if (way == null) return this;
if (way.isNew()) return this;
for (Node node: way.getNodes()) {
if (!node.isNew()) {
remember(node.getPrimitiveId());
}
}
remember(way.getPrimitiveId());
return this;
}
/**
* appends a {@see Relation}s id to the list of ids which will be fetched from the server.
*
* @param relation the relation (ignored, if null)
* @return this
*
*/
public MultiFetchServerObjectReader append(Relation relation) {
if (relation == null) return this;
if (relation.isNew()) return this;
remember(relation.getPrimitiveId());
for (RelationMember member : relation.getMembers()) {
if (OsmPrimitiveType.from(member.getMember()).equals(OsmPrimitiveType.RELATION)) {
// avoid infinite recursion in case of cyclic dependencies in relations
//
if (relations.contains(member.getMember().getId())) {
continue;
}
}
if (!member.getMember().isIncomplete()) {
appendGeneric(member.getMember());
}
}
return this;
}
protected MultiFetchServerObjectReader appendGeneric(OsmPrimitive primitive) {
if (OsmPrimitiveType.from(primitive).equals(OsmPrimitiveType.NODE))
return append((Node)primitive);
else if (OsmPrimitiveType.from(primitive).equals(OsmPrimitiveType.WAY))
return append((Way)primitive);
else if (OsmPrimitiveType.from(primitive).equals(OsmPrimitiveType.RELATION))
return append((Relation)primitive);
return this;
}
/**
* appends a list of {@see OsmPrimitive} to the list of ids which will be fetched from the server.
*
* @param primitives the list of primitives (ignored, if null)
* @return this
*
* @see #append(Node)
* @see #append(Way)
* @see #append(Relation)
*
*/
public MultiFetchServerObjectReader append(Collection<? extends OsmPrimitive> primitives) {
if (primitives == null) return this;
for (OsmPrimitive primitive : primitives) {
appendGeneric(primitive);
}
return this;
}
/**
* extracts a subset of max {@see #MAX_IDS_PER_REQUEST} ids from <code>ids</code> and
* replies the subset. The extracted subset is removed from <code>ids</code>.
*
* @param ids a set of ids
* @return the subset of ids
*/
protected Set<Long> extractIdPackage(Set<Long> ids) {
HashSet<Long> pkg = new HashSet<Long>();
if (ids.isEmpty())
return pkg;
if (ids.size() > MAX_IDS_PER_REQUEST) {
Iterator<Long> it = ids.iterator();
for (int i =0;i<MAX_IDS_PER_REQUEST;i++) {
pkg.add(it.next());
}
ids.removeAll(pkg);
} else {
pkg.addAll(ids);
ids.clear();
}
return pkg;
}
/**
* builds the Multi Get request string for a set of ids and a given
* {@see OsmPrimitiveType}.
*
* @param type the type
* @param idPackage the package of ids
* @return the request string
*/
protected String buildRequestString(OsmPrimitiveType type, Set<Long> idPackage) {
StringBuilder sb = new StringBuilder();
sb.append(type.getAPIName()).append("s?")
.append(type.getAPIName()).append("s=");
Iterator<Long> it = idPackage.iterator();
for (int i=0; i< idPackage.size();i++) {
sb.append(it.next());
if (i < idPackage.size()-1) {
sb.append(",");
}
}
return sb.toString();
}
/**
* builds the Multi Get request string for a single id and a given
* {@see OsmPrimitiveType}.
*
* @param type the type
* @param id the id
* @return the request string
*/
protected String buildRequestString(OsmPrimitiveType type, long id) {
StringBuilder sb = new StringBuilder();
sb.append(type.getAPIName()).append("s?")
.append(type.getAPIName()).append("s=")
.append(id);
return sb.toString();
}
/**
* invokes a Multi Get for a set of ids and a given {@see OsmPrimitiveType}.
* The retrieved primitives are merged to {@see #outputDataSet}.
*
* @param type the type
* @param pkg the package of ids
* @exception OsmTransferException thrown if an error occurs while communicating with the API server
*
*/
protected void multiGetIdPackage(OsmPrimitiveType type, Set<Long> pkg, ProgressMonitor progressMonitor) throws OsmTransferException {
String request = buildRequestString(type, pkg);
final InputStream in = getInputStream(request, NullProgressMonitor.INSTANCE);
if (in == null) return;
progressMonitor.subTask(tr("Downloading OSM data..."));
try {
DataSet loaded = OsmReader.parseDataSet(in, progressMonitor.createSubTaskMonitor(ProgressMonitor.ALL_TICKS, false));
rememberNodesOfIncompleteWaysToLoad(loaded);
merge(loaded);
} catch(Exception e) {
throw new OsmTransferException(e);
}
}
/**
* invokes a Multi Get for a single id and a given {@see OsmPrimitiveType}.
* The retrieved primitive is merged to {@see #outputDataSet}.
*
* @param type the type
* @param id the id
* @exception OsmTransferException thrown if an error occurs while communicating with the API server
*
*/
protected void singleGetId(OsmPrimitiveType type, long id, ProgressMonitor progressMonitor) throws OsmTransferException {
String request = buildRequestString(type, id);
final InputStream in = getInputStream(request, NullProgressMonitor.INSTANCE);
if (in == null)
return;
progressMonitor.subTask(tr("Downloading OSM data..."));
try {
DataSet loaded = OsmReader.parseDataSet(in, progressMonitor.createSubTaskMonitor(ProgressMonitor.ALL_TICKS, false));
rememberNodesOfIncompleteWaysToLoad(loaded);
merge(loaded);
} catch(Exception e) {
throw new OsmTransferException(e);
}
}
/**
* invokes a sequence of Multi Gets for individual ids in a set of ids and a given {@see OsmPrimitiveType}.
* The retrieved primitives are merged to {@see #outputDataSet}.
*
* This method is used if one of the ids in pkg doesn't exist (the server replies with return code 404).
* If the set is fetched with this method it is possible to find out which of the ids doesn't exist.
* Unfortunatelly, the server does not provide an error header or an error body for a 404 reply.
*
* @param type the type
* @param pkg the set of ids
* @exception OsmTransferException thrown if an error occurs while communicating with the API server
*
*/
protected void singleGetIdPackage(OsmPrimitiveType type, Set<Long> pkg, ProgressMonitor progressMonitor) throws OsmTransferException {
for (long id : pkg) {
try {
String msg = "";
switch(type) {
case NODE: msg = tr("Fetching node with id {0} from ''{1}''", id, OsmApi.getOsmApi().getBaseUrl()); break;
case WAY: msg = tr("Fetching way with id {0} from ''{1}''", id, OsmApi.getOsmApi().getBaseUrl()); break;
case RELATION: msg = tr("Fetching relation with id {0} from ''{1}''", id, OsmApi.getOsmApi().getBaseUrl()); break;
}
progressMonitor.setCustomText(msg);
singleGetId(type, id, progressMonitor);
} catch(OsmApiException e) {
if (e.getResponseCode() == HttpURLConnection.HTTP_NOT_FOUND) {
logger.warning(tr("Server replied with response code 404 for id {0}. Skipping.", Long.toString(id)));
missingPrimitives.add(id);
continue;
}
throw e;
}
}
}
protected void rememberNodesOfIncompleteWaysToLoad(DataSet from) {
for (Way w: from.getWays()) {
if (w.hasIncompleteNodes()) {
for (Node n: w.getNodes()) {
if (n.isIncomplete()) {
nodes.add(n.getId());
}
}
}
}
}
/**
* merges the dataset <code>from</code> to {@see #outputDataSet}.
*
* @param from the other dataset
*
*/
protected void merge(DataSet from) {
final DataSetMerger visitor = new DataSetMerger(outputDataSet,from);
visitor.merge();
}
/**
* fetches a set of ids of a given {@see OsmPrimitiveType} from the server
*
* @param ids the set of ids
* @param type the type
* @exception OsmTransferException thrown if an error occurs while communicating with the API server
*/
protected void fetchPrimitives(Set<Long> ids, OsmPrimitiveType type, ProgressMonitor progressMonitor) throws OsmTransferException{
String msg = "";
switch(type) {
case NODE: msg = tr("Fetching a package of nodes from ''{0}''", OsmApi.getOsmApi().getBaseUrl()); break;
case WAY: msg = tr("Fetching a package of ways from ''{0}''", OsmApi.getOsmApi().getBaseUrl()); break;
case RELATION: msg = tr("Fetching a package of relations from ''{0}''", OsmApi.getOsmApi().getBaseUrl()); break;
}
progressMonitor.indeterminateSubTask(msg);
Set<Long> toFetch = new HashSet<Long>(ids);
toFetch.addAll(ids);
while(! toFetch.isEmpty() && !isCanceled()) {
Set<Long> pkg = extractIdPackage(toFetch);
try {
multiGetIdPackage(type, pkg, progressMonitor);
} catch(OsmApiException e) {
if (e.getResponseCode() == HttpURLConnection.HTTP_NOT_FOUND) {
logger.warning(tr("Server replied with response code 404, retrying with an individual request for each primitive."));
singleGetIdPackage(type, pkg, progressMonitor);
} else
throw e;
}
}
}
/**
* invokes one or more Multi Gets to fetch the {@see OsmPrimitive}s and replies
* the dataset of retrieved primitives. Note that the dataset includes non visible primitives too!
* In contrast to a simple Get for a node, a way, or a relation, a Multi Get always replies
* the latest version of the primitive (if any), even if the primitive is not visible (i.e. if
* visible==false).
*
* Invoke {@see #getMissingPrimitives()} to get a list of primitives which have not been
* found on the server (the server response code was 404)
*
* @return the parsed data
* @exception OsmTransferException thrown if an error occurs while communicating with the API server
* @see #getMissingPrimitives()
*
*/
@Override
public DataSet parseOsm(ProgressMonitor progressMonitor) throws OsmTransferException {
int n = nodes.size() + ways.size() + relations.size();
progressMonitor.beginTask(trn("Downloading {0} object from ''{1}''", "Downloading {0} objects from ''{1}''", n, n, OsmApi.getOsmApi().getBaseUrl()));
try {
missingPrimitives = new HashSet<Long>();
if (isCanceled())return null;
fetchPrimitives(ways,OsmPrimitiveType.WAY, progressMonitor);
if (isCanceled())return null;
fetchPrimitives(nodes,OsmPrimitiveType.NODE, progressMonitor);
if (isCanceled())return null;
fetchPrimitives(relations,OsmPrimitiveType.RELATION, progressMonitor);
return outputDataSet;
} finally {
progressMonitor.finishTask();
}
}
/**
* replies the set of ids of all primitives for which a fetch request to the
* server was submitted but which are not available from the server (the server
* replied a return code of 404)
*
* @return the set of ids of missing primitives
*/
public Set<Long> getMissingPrimitives() {
return missingPrimitives;
}
}