// 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.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import org.openstreetmap.josm.Main;
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.SimplePrimitiveId;
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 {@link 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()) {
* Main.info("There are missing primitives: " + reader.getMissingPrimitives());
* }
* if (!reader.getSkippedWays().isEmpty()) {
* Main.info("There are skipped ways: " + reader.getMissingPrimitives());
* }
* </pre>
*/
public class MultiFetchServerObjectReader extends OsmServerReader{
/**
* 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>.
*/
private static final int MAX_IDS_PER_REQUEST = 200;
private Set<Long> nodes;
private Set<Long> ways;
private Set<Long> relations;
private Set<PrimitiveId> missingPrimitives;
private DataSet outputDataSet;
/**
* Constructs a {@code MultiFetchServerObjectReader}.
*/
public MultiFetchServerObjectReader() {
nodes = new LinkedHashSet<>();
ways = new LinkedHashSet<>();
relations = new LinkedHashSet<>();
this.outputDataSet = new DataSet();
this.missingPrimitives = new LinkedHashSet<>();
}
/**
* Remembers an {@link 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 {@link OsmPrimitive}'s id. <code>ds</code> must include
* an {@link 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 primitive id
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @throws IllegalArgumentException if ds is null
* @throws NoSuchElementException if ds does not include an {@link 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 {@link OsmPrimitive} id to the list of ids which will be fetched from the server.
*
* @param ds the {@link DataSet} to which the primitive belongs
* @param id the primitive id
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @return this
*/
public MultiFetchServerObjectReader append(DataSet ds, long id, OsmPrimitiveType type) {
OsmPrimitive p = ds.getPrimitiveById(id,type);
switch(type) {
case NODE:
return appendNode((Node)p);
case WAY:
return appendWay((Way)p);
case RELATION:
return appendRelation((Relation)p);
}
return this;
}
/**
* appends a {@link Node} id to the list of ids which will be fetched from the server.
*
* @param node the node (ignored, if null)
* @return this
*/
public MultiFetchServerObjectReader appendNode(Node node) {
if (node == null) return this;
remember(node.getPrimitiveId());
return this;
}
/**
* appends a {@link Way} 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 appendWay(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 {@link Relation} id to the list of ids which will be fetched from the server.
*
* @param relation the relation (ignored, if null)
* @return this
*/
protected MultiFetchServerObjectReader appendRelation(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()) {
append(member.getMember());
}
}
return this;
}
/**
* appends an {@link OsmPrimitive} to the list of ids which will be fetched from the server.
* @param primitive the primitive
* @return this
*/
public MultiFetchServerObjectReader append(OsmPrimitive primitive) {
if (primitive != null) {
switch (OsmPrimitiveType.from(primitive)) {
case NODE: return appendNode((Node)primitive);
case WAY: return appendWay((Way)primitive);
case RELATION: return appendRelation((Relation)primitive);
}
}
return this;
}
/**
* appends a list of {@link 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(OsmPrimitive)
*/
public MultiFetchServerObjectReader append(Collection<? extends OsmPrimitive> primitives) {
if (primitives == null) return this;
for (OsmPrimitive primitive : primitives) {
append(primitive);
}
return this;
}
/**
* extracts a subset of max {@link #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<>();
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
* {@link OsmPrimitiveType}.
*
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @param idPackage the package of ids
* @return the request string
*/
protected static 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
* {@link OsmPrimitiveType}.
*
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @param id the id
* @return the request string
*/
protected static 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();
}
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 {@link #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 {@link OsmPrimitiveType} from the server
*
* @param ids the set of ids
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @throws OsmTransferException if an error occurs while communicating with the API server
*/
protected void fetchPrimitives(Set<Long> ids, OsmPrimitiveType type, ProgressMonitor progressMonitor) throws OsmTransferException {
String msg = "";
String baseUrl = OsmApi.getOsmApi().getBaseUrl();
switch (type) {
case NODE: msg = tr("Fetching a package of nodes from ''{0}''", baseUrl); break;
case WAY: msg = tr("Fetching a package of ways from ''{0}''", baseUrl); break;
case RELATION: msg = tr("Fetching a package of relations from ''{0}''", baseUrl); break;
}
progressMonitor.setTicksCount(ids.size());
progressMonitor.setTicks(0);
// The complete set containg all primitives to fetch
Set<Long> toFetch = new HashSet<>(ids);
// Build a list of fetchers that will download smaller sets containing only MAX_IDS_PER_REQUEST (200) primitives each.
// we will run up to MAX_DOWNLOAD_THREADS concurrent fetchers.
int threadsNumber = Main.pref.getInteger("osm.download.threads", OsmApi.MAX_DOWNLOAD_THREADS);
threadsNumber = Math.min(Math.max(threadsNumber, 1), OsmApi.MAX_DOWNLOAD_THREADS);
Executor exec = Executors.newFixedThreadPool(threadsNumber);
CompletionService<FetchResult> ecs = new ExecutorCompletionService<>(exec);
List<Future<FetchResult>> jobs = new ArrayList<>();
while (!toFetch.isEmpty()) {
jobs.add(ecs.submit(new Fetcher(type, extractIdPackage(toFetch), progressMonitor)));
}
// Run the fetchers
for (int i = 0; i < jobs.size() && !isCanceled(); i++) {
progressMonitor.subTask(msg + "... " + progressMonitor.getTicks() + "/" + progressMonitor.getTicksCount());
try {
FetchResult result = ecs.take().get();
if (result.missingPrimitives != null) {
missingPrimitives.addAll(result.missingPrimitives);
}
if (result.dataSet != null && !isCanceled()) {
rememberNodesOfIncompleteWaysToLoad(result.dataSet);
merge(result.dataSet);
}
} catch (InterruptedException | ExecutionException e) {
Main.error(e);
}
}
// Cancel requests if the user choosed to
if (isCanceled()) {
for (Future<FetchResult> job : jobs) {
job.cancel(true);
}
}
}
/**
* invokes one or more Multi Gets to fetch the {@link 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 {@link #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
* @throws OsmTransferException 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<>();
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);
if (outputDataSet != null) {
outputDataSet.deleteInvisible();
}
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<PrimitiveId> getMissingPrimitives() {
return missingPrimitives;
}
/**
* The class holding the results given by {@link Fetcher}.
* It is only a wrapper of the resulting {@link DataSet} and the collection of {@link PrimitiveId} that could not have been loaded.
*/
protected static class FetchResult {
/**
* The resulting data set
*/
public final DataSet dataSet;
/**
* The collection of primitive ids that could not have been loaded
*/
public final Set<PrimitiveId> missingPrimitives;
/**
* Constructs a {@code FetchResult}
* @param dataSet The resulting data set
* @param missingPrimitives The collection of primitive ids that could not have been loaded
*/
public FetchResult(DataSet dataSet, Set<PrimitiveId> missingPrimitives) {
this.dataSet = dataSet;
this.missingPrimitives = missingPrimitives;
}
}
/**
* The class that actually download data from OSM API. Several instances of this class are used by {@link MultiFetchServerObjectReader} (one per set of primitives to fetch).
* The inheritance of {@link OsmServerReader} is only explained by the need to have a distinct OSM connection by {@code Fetcher} instance.
* @see FetchResult
*/
protected static class Fetcher extends OsmServerReader implements Callable<FetchResult> {
private final Set<Long> pkg;
private final OsmPrimitiveType type;
private final ProgressMonitor progressMonitor;
/**
* Constructs a {@code Fetcher}
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @param idsPackage The set of primitives ids to fetch
* @param progressMonitor The progress monitor
*/
public Fetcher(OsmPrimitiveType type, Set<Long> idsPackage, ProgressMonitor progressMonitor) {
this.pkg = idsPackage;
this.type = type;
this.progressMonitor = progressMonitor;
}
@Override
public DataSet parseOsm(ProgressMonitor progressMonitor) throws OsmTransferException {
// This method is implemented because of the OsmServerReader inheritance, but not used, as the main target of this class is the call() method.
return fetch(progressMonitor).dataSet;
}
@Override
public FetchResult call() throws Exception {
return fetch(progressMonitor);
}
/**
* fetches the requested primitives and updates the specified progress monitor.
* @param progressMonitor the progress monitor
* @return the {@link FetchResult} of this operation
* @throws OsmTransferException if an error occurs while communicating with the API server
*/
protected FetchResult fetch(ProgressMonitor progressMonitor) throws OsmTransferException {
try {
return multiGetIdPackage(type, pkg, progressMonitor);
} catch (OsmApiException e) {
if (e.getResponseCode() == HttpURLConnection.HTTP_NOT_FOUND) {
Main.info(tr("Server replied with response code 404, retrying with an individual request for each object."));
return singleGetIdPackage(type, pkg, progressMonitor);
} else {
throw e;
}
}
}
/**
* invokes a Multi Get for a set of ids and a given {@link OsmPrimitiveType}.
* The retrieved primitives are merged to {@link #outputDataSet}.
*
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @param pkg the package of ids
* @return the {@link FetchResult} of this operation
* @throws OsmTransferException if an error occurs while communicating with the API server
*/
protected FetchResult multiGetIdPackage(OsmPrimitiveType type, Set<Long> pkg, ProgressMonitor progressMonitor) throws OsmTransferException {
String request = buildRequestString(type, pkg);
FetchResult result = null;
try (InputStream in = getInputStream(request, NullProgressMonitor.INSTANCE)) {
if (in == null) return null;
progressMonitor.subTask(tr("Downloading OSM data..."));
try {
result = new FetchResult(OsmReader.parseDataSet(in, progressMonitor.createSubTaskMonitor(pkg.size(), false)), null);
} catch (Exception e) {
throw new OsmTransferException(e);
}
} catch (IOException ex) {
Main.warn(ex);
}
return result;
}
/**
* invokes a Multi Get for a single id and a given {@link OsmPrimitiveType}.
* The retrieved primitive is merged to {@link #outputDataSet}.
*
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @param id the id
* @return the {@link DataSet} resulting of this operation
* @throws OsmTransferException if an error occurs while communicating with the API server
*/
protected DataSet singleGetId(OsmPrimitiveType type, long id, ProgressMonitor progressMonitor) throws OsmTransferException {
String request = buildRequestString(type, id);
DataSet result = null;
try (InputStream in = getInputStream(request, NullProgressMonitor.INSTANCE)) {
if (in == null) return null;
progressMonitor.subTask(tr("Downloading OSM data..."));
try {
result = OsmReader.parseDataSet(in, progressMonitor.createSubTaskMonitor(1, false));
} catch (Exception e) {
throw new OsmTransferException(e);
}
} catch (IOException ex) {
Main.warn(ex);
}
return result;
}
/**
* invokes a sequence of Multi Gets for individual ids in a set of ids and a given {@link OsmPrimitiveType}.
* The retrieved primitives are merged to {@link #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.
* Unfortunately, the server does not provide an error header or an error body for a 404 reply.
*
* @param type The primitive type. Must be one of {@link OsmPrimitiveType#NODE NODE}, {@link OsmPrimitiveType#WAY WAY}, {@link OsmPrimitiveType#RELATION RELATION}
* @param pkg the set of ids
* @return the {@link FetchResult} of this operation
* @throws OsmTransferException if an error occurs while communicating with the API server
*/
protected FetchResult singleGetIdPackage(OsmPrimitiveType type, Set<Long> pkg, ProgressMonitor progressMonitor) throws OsmTransferException {
FetchResult result = new FetchResult(new DataSet(), new HashSet<PrimitiveId>());
String baseUrl = OsmApi.getOsmApi().getBaseUrl();
for (long id : pkg) {
try {
String msg = "";
switch (type) {
case NODE: msg = tr("Fetching node with id {0} from ''{1}''", id, baseUrl); break;
case WAY: msg = tr("Fetching way with id {0} from ''{1}''", id, baseUrl); break;
case RELATION: msg = tr("Fetching relation with id {0} from ''{1}''", id, baseUrl); break;
}
progressMonitor.setCustomText(msg);
result.dataSet.mergeFrom(singleGetId(type, id, progressMonitor));
} catch (OsmApiException e) {
if (e.getResponseCode() == HttpURLConnection.HTTP_NOT_FOUND) {
Main.info(tr("Server replied with response code 404 for id {0}. Skipping.", Long.toString(id)));
result.missingPrimitives.add(new SimplePrimitiveId(id, type));
} else {
throw e;
}
}
}
return result;
}
}
}