001//License: GPL. See README for details.
002package org.openstreetmap.josm.io;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005import static org.openstreetmap.josm.tools.I18n.trn;
006
007import java.io.BufferedReader;
008import java.io.BufferedWriter;
009import java.io.IOException;
010import java.io.InputStream;
011import java.io.InputStreamReader;
012import java.io.OutputStream;
013import java.io.OutputStreamWriter;
014import java.io.PrintWriter;
015import java.io.StringReader;
016import java.io.StringWriter;
017import java.io.UnsupportedEncodingException;
018import java.net.ConnectException;
019import java.net.HttpURLConnection;
020import java.net.MalformedURLException;
021import java.net.SocketTimeoutException;
022import java.net.URL;
023import java.net.URLEncoder;
024import java.nio.charset.StandardCharsets;
025import java.util.Collection;
026import java.util.Collections;
027import java.util.HashMap;
028import java.util.List;
029import java.util.Map;
030
031import javax.xml.parsers.ParserConfigurationException;
032
033import org.openstreetmap.josm.Main;
034import org.openstreetmap.josm.data.coor.LatLon;
035import org.openstreetmap.josm.data.notes.Note;
036import org.openstreetmap.josm.data.osm.Changeset;
037import org.openstreetmap.josm.data.osm.IPrimitive;
038import org.openstreetmap.josm.data.osm.OsmPrimitive;
039import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
040import org.openstreetmap.josm.gui.layer.ImageryLayer;
041import org.openstreetmap.josm.gui.layer.Layer;
042import org.openstreetmap.josm.gui.progress.NullProgressMonitor;
043import org.openstreetmap.josm.gui.progress.ProgressMonitor;
044import org.openstreetmap.josm.io.Capabilities.CapabilitiesParser;
045import org.openstreetmap.josm.tools.CheckParameterUtil;
046import org.openstreetmap.josm.tools.Utils;
047import org.openstreetmap.josm.tools.XmlParsingException;
048import org.xml.sax.InputSource;
049import org.xml.sax.SAXException;
050import org.xml.sax.SAXParseException;
051
052/**
053 * Class that encapsulates the communications with the <a href="http://wiki.openstreetmap.org/wiki/API_v0.6">OSM API</a>.<br><br>
054 *
055 * All interaction with the server-side OSM API should go through this class.<br><br>
056 *
057 * It is conceivable to extract this into an interface later and create various
058 * classes implementing the interface, to be able to talk to various kinds of servers.
059 *
060 */
061public class OsmApi extends OsmConnection {
062
063    /**
064     * Maximum number of retries to send a request in case of HTTP 500 errors or timeouts
065     */
066    public static final int DEFAULT_MAX_NUM_RETRIES = 5;
067
068    /**
069     * Maximum number of concurrent download threads, imposed by
070     * <a href="http://wiki.openstreetmap.org/wiki/API_usage_policy#Technical_Usage_Requirements">
071     * OSM API usage policy.</a>
072     * @since 5386
073     */
074    public static final int MAX_DOWNLOAD_THREADS = 2;
075
076    /**
077     * Default URL of the standard OSM API.
078     * @since 5422
079     */
080    public static final String DEFAULT_API_URL = "https://api.openstreetmap.org/api";
081
082    // The collection of instantiated OSM APIs
083    private static Map<String, OsmApi> instances = new HashMap<>();
084
085    private URL url = null;
086
087    /**
088     * Replies the {@link OsmApi} for a given server URL
089     *
090     * @param serverUrl  the server URL
091     * @return the OsmApi
092     * @throws IllegalArgumentException thrown, if serverUrl is null
093     *
094     */
095    public static OsmApi getOsmApi(String serverUrl) {
096        OsmApi api = instances.get(serverUrl);
097        if (api == null) {
098            api = new OsmApi(serverUrl);
099            instances.put(serverUrl,api);
100        }
101        return api;
102    }
103
104    private static String getServerUrlFromPref() {
105        return Main.pref.get("osm-server.url", DEFAULT_API_URL);
106    }
107
108    /**
109     * Replies the {@link OsmApi} for the URL given by the preference <code>osm-server.url</code>
110     *
111     * @return the OsmApi
112     */
113    public static OsmApi getOsmApi() {
114        return getOsmApi(getServerUrlFromPref());
115    }
116
117    /** Server URL */
118    private String serverUrl;
119
120    /** Object describing current changeset */
121    private Changeset changeset;
122
123    /** API version used for server communications */
124    private String version = null;
125
126    /** API capabilities */
127    private Capabilities capabilities = null;
128
129    /** true if successfully initialized */
130    private boolean initialized = false;
131
132    /**
133     * Constructs a new {@code OsmApi} for a specific server URL.
134     *
135     * @param serverUrl the server URL. Must not be null
136     * @throws IllegalArgumentException thrown, if serverUrl is null
137     */
138    protected OsmApi(String serverUrl)  {
139        CheckParameterUtil.ensureParameterNotNull(serverUrl, "serverUrl");
140        this.serverUrl = serverUrl;
141    }
142
143    /**
144     * Replies the OSM protocol version we use to talk to the server.
145     * @return protocol version, or null if not yet negotiated.
146     */
147    public String getVersion() {
148        return version;
149    }
150
151    /**
152     * Replies the host name of the server URL.
153     * @return the host name of the server URL, or null if the server URL is malformed.
154     */
155    public String getHost() {
156        String host = null;
157        try {
158            host = (new URL(serverUrl)).getHost();
159        } catch (MalformedURLException e) {
160            Main.warn(e);
161        }
162        return host;
163    }
164
165    private class CapabilitiesCache extends CacheCustomContent<OsmTransferException> {
166
167        private static final String CAPABILITIES = "capabilities";
168
169        ProgressMonitor monitor;
170        boolean fastFail;
171
172        public CapabilitiesCache(ProgressMonitor monitor, boolean fastFail) {
173            super(CAPABILITIES + getBaseUrl().hashCode(), CacheCustomContent.INTERVAL_WEEKLY);
174            this.monitor = monitor;
175            this.fastFail = fastFail;
176        }
177
178        @Override
179        protected void checkOfflineAccess() {
180            OnlineResource.OSM_API.checkOfflineAccess(getBaseUrl(getServerUrlFromPref(), "0.6")+CAPABILITIES, getServerUrlFromPref());
181        }
182
183        @Override
184        protected byte[] updateData() throws OsmTransferException {
185            return sendRequest("GET", CAPABILITIES, null, monitor, false, fastFail).getBytes(StandardCharsets.UTF_8);
186        }
187    }
188
189    /**
190     * Initializes this component by negotiating a protocol version with the server.
191     *
192     * @param monitor the progress monitor
193     * @throws OsmTransferCanceledException If the initialisation has been cancelled by user.
194     * @throws OsmApiInitializationException If any other exception occurs. Use getCause() to get the original exception.
195     */
196    public void initialize(ProgressMonitor monitor) throws OsmTransferCanceledException, OsmApiInitializationException {
197        initialize(monitor, false);
198    }
199
200    /**
201     * Initializes this component by negotiating a protocol version with the server, with the ability to control the timeout.
202     *
203     * @param monitor the progress monitor
204     * @param fastFail true to request quick initialisation with a small timeout (more likely to throw exception)
205     * @throws OsmTransferCanceledException If the initialisation has been cancelled by user.
206     * @throws OsmApiInitializationException If any other exception occurs. Use getCause() to get the original exception.
207     */
208    public void initialize(ProgressMonitor monitor, boolean fastFail) throws OsmTransferCanceledException, OsmApiInitializationException {
209        if (initialized)
210            return;
211        cancel = false;
212        try {
213            CapabilitiesCache cache = new CapabilitiesCache(monitor, fastFail);
214            try {
215                initializeCapabilities(cache.updateIfRequiredString());
216            } catch (SAXParseException parseException) {
217                // XML parsing may fail if JOSM previously stored a corrupted capabilities document (see #8278)
218                // In that case, force update and try again
219                initializeCapabilities(cache.updateForceString());
220            }
221            if (capabilities == null) {
222                if (Main.isOffline(OnlineResource.OSM_API)) {
223                    Main.warn(tr("{0} not available (offline mode)", tr("OSM API")));
224                } else {
225                    Main.error(tr("Unable to initialize OSM API."));
226                }
227                return;
228            } else if (!capabilities.supportsVersion("0.6")) {
229                Main.error(tr("This version of JOSM is incompatible with the configured server."));
230                Main.error(tr("It supports protocol version 0.6, while the server says it supports {0} to {1}.",
231                        capabilities.get("version", "minimum"), capabilities.get("version", "maximum")));
232                return;
233            } else {
234                version = "0.6";
235                initialized = true;
236            }
237
238            /* This is an interim solution for openstreetmap.org not currently
239             * transmitting their imagery blacklist in the capabilities call.
240             * remove this as soon as openstreetmap.org adds blacklists.
241             * If you want to update this list, please ask for update of
242             * http://trac.openstreetmap.org/ticket/5024
243             * This list should not be maintained by each OSM editor (see #9210) */
244            if (this.serverUrl.matches(".*openstreetmap.org/api.*") && capabilities.getImageryBlacklist().isEmpty()) {
245                capabilities.put("blacklist", "regex", ".*\\.google\\.com/.*");
246                capabilities.put("blacklist", "regex", ".*209\\.85\\.2\\d\\d.*");
247                capabilities.put("blacklist", "regex", ".*209\\.85\\.1[3-9]\\d.*");
248                capabilities.put("blacklist", "regex", ".*209\\.85\\.12[89].*");
249            }
250
251            /* This checks if there are any layers currently displayed that
252             * are now on the blacklist, and removes them. This is a rare
253             * situation - probably only occurs if the user changes the API URL
254             * in the preferences menu. Otherwise they would not have been able
255             * to load the layers in the first place because they would have
256             * been disabled! */
257            if (Main.isDisplayingMapView()) {
258                for (Layer l : Main.map.mapView.getLayersOfType(ImageryLayer.class)) {
259                    if (((ImageryLayer) l).getInfo().isBlacklisted()) {
260                        Main.info(tr("Removed layer {0} because it is not allowed by the configured API.", l.getName()));
261                        Main.main.removeLayer(l);
262                    }
263                }
264            }
265
266        } catch (OsmTransferCanceledException e) {
267            throw e;
268        } catch (OsmTransferException e) {
269            initialized = false;
270            Main.addNetworkError(url, Utils.getRootCause(e));
271            throw new OsmApiInitializationException(e);
272        } catch (Exception e) {
273            initialized = false;
274            throw new OsmApiInitializationException(e);
275        }
276    }
277
278    private synchronized void initializeCapabilities(String xml) throws SAXException, IOException, ParserConfigurationException {
279        if (xml != null) {
280            capabilities = CapabilitiesParser.parse(new InputSource(new StringReader(xml)));
281        }
282    }
283
284    /**
285     * Makes an XML string from an OSM primitive. Uses the OsmWriter class.
286     * @param o the OSM primitive
287     * @param addBody true to generate the full XML, false to only generate the encapsulating tag
288     * @return XML string
289     */
290    private String toXml(IPrimitive o, boolean addBody) {
291        StringWriter swriter = new StringWriter();
292        try (OsmWriter osmWriter = OsmWriterFactory.createOsmWriter(new PrintWriter(swriter), true, version)) {
293            swriter.getBuffer().setLength(0);
294            osmWriter.setWithBody(addBody);
295            osmWriter.setChangeset(changeset);
296            osmWriter.header();
297            o.accept(osmWriter);
298            osmWriter.footer();
299            osmWriter.flush();
300        } catch (IOException e) {
301            Main.warn(e);
302        }
303        return swriter.toString();
304    }
305
306    /**
307     * Makes an XML string from an OSM primitive. Uses the OsmWriter class.
308     * @param s the changeset
309     * @return XML string
310     */
311    private String toXml(Changeset s) {
312        StringWriter swriter = new StringWriter();
313        try (OsmWriter osmWriter = OsmWriterFactory.createOsmWriter(new PrintWriter(swriter), true, version)) {
314            swriter.getBuffer().setLength(0);
315            osmWriter.header();
316            osmWriter.visit(s);
317            osmWriter.footer();
318            osmWriter.flush();
319        } catch (IOException e) {
320            Main.warn(e);
321        }
322        return swriter.toString();
323    }
324
325    private static String getBaseUrl(String serverUrl, String version) {
326        StringBuilder rv = new StringBuilder(serverUrl);
327        if (version != null) {
328            rv.append("/");
329            rv.append(version);
330        }
331        rv.append("/");
332        // this works around a ruby (or lighttpd) bug where two consecutive slashes in
333        // an URL will cause a "404 not found" response.
334        int p;
335        while ((p = rv.indexOf("//", rv.indexOf("://")+2)) > -1) {
336            rv.delete(p, p + 1);
337        }
338        return rv.toString();
339    }
340
341    /**
342     * Returns the base URL for API requests, including the negotiated version number.
343     * @return base URL string
344     */
345    public String getBaseUrl() {
346        return getBaseUrl(serverUrl, version);
347    }
348
349    /**
350     * Creates an OSM primitive on the server. The OsmPrimitive object passed in
351     * is modified by giving it the server-assigned id.
352     *
353     * @param osm the primitive
354     * @param monitor the progress monitor
355     * @throws OsmTransferException if something goes wrong
356     */
357    public void createPrimitive(IPrimitive osm, ProgressMonitor monitor) throws OsmTransferException {
358        String ret = "";
359        try {
360            ensureValidChangeset();
361            initialize(monitor);
362            ret = sendRequest("PUT", OsmPrimitiveType.from(osm).getAPIName()+"/create", toXml(osm, true),monitor);
363            osm.setOsmId(Long.parseLong(ret.trim()), 1);
364            osm.setChangesetId(getChangeset().getId());
365        } catch(NumberFormatException e){
366            throw new OsmTransferException(tr("Unexpected format of ID replied by the server. Got ''{0}''.", ret));
367        }
368    }
369
370    /**
371     * Modifies an OSM primitive on the server.
372     *
373     * @param osm the primitive. Must not be null.
374     * @param monitor the progress monitor
375     * @throws OsmTransferException if something goes wrong
376     */
377    public void modifyPrimitive(IPrimitive osm, ProgressMonitor monitor) throws OsmTransferException {
378        String ret = null;
379        try {
380            ensureValidChangeset();
381            initialize(monitor);
382            // normal mode (0.6 and up) returns new object version.
383            ret = sendRequest("PUT", OsmPrimitiveType.from(osm).getAPIName()+"/" + osm.getId(), toXml(osm, true), monitor);
384            osm.setOsmId(osm.getId(), Integer.parseInt(ret.trim()));
385            osm.setChangesetId(getChangeset().getId());
386            osm.setVisible(true);
387        } catch(NumberFormatException e) {
388            throw new OsmTransferException(tr("Unexpected format of new version of modified primitive ''{0}''. Got ''{1}''.",
389                    osm.getId(), ret));
390        }
391    }
392
393    /**
394     * Deletes an OSM primitive on the server.
395     * @param osm the primitive
396     * @param monitor the progress monitor
397     * @throws OsmTransferException if something goes wrong
398     */
399    public void deletePrimitive(OsmPrimitive osm, ProgressMonitor monitor) throws OsmTransferException {
400        ensureValidChangeset();
401        initialize(monitor);
402        // can't use a the individual DELETE method in the 0.6 API. Java doesn't allow
403        // submitting a DELETE request with content, the 0.6 API requires it, however. Falling back
404        // to diff upload.
405        //
406        uploadDiff(Collections.singleton(osm), monitor.createSubTaskMonitor(ProgressMonitor.ALL_TICKS, false));
407    }
408
409    /**
410     * Creates a new changeset based on the keys in <code>changeset</code>. If this
411     * method succeeds, changeset.getId() replies the id the server assigned to the new
412     * changeset
413     *
414     * The changeset must not be null, but its key/value-pairs may be empty.
415     *
416     * @param changeset the changeset toe be created. Must not be null.
417     * @param progressMonitor the progress monitor
418     * @throws OsmTransferException signifying a non-200 return code, or connection errors
419     * @throws IllegalArgumentException thrown if changeset is null
420     */
421    public void openChangeset(Changeset changeset, ProgressMonitor progressMonitor) throws OsmTransferException {
422        CheckParameterUtil.ensureParameterNotNull(changeset, "changeset");
423        try {
424            progressMonitor.beginTask((tr("Creating changeset...")));
425            initialize(progressMonitor);
426            String ret = "";
427            try {
428                ret = sendRequest("PUT", "changeset/create", toXml(changeset),progressMonitor);
429                changeset.setId(Integer.parseInt(ret.trim()));
430                changeset.setOpen(true);
431            } catch(NumberFormatException e){
432                throw new OsmTransferException(tr("Unexpected format of ID replied by the server. Got ''{0}''.", ret));
433            }
434            progressMonitor.setCustomText((tr("Successfully opened changeset {0}",changeset.getId())));
435        } finally {
436            progressMonitor.finishTask();
437        }
438    }
439
440    /**
441     * Updates a changeset with the keys in  <code>changesetUpdate</code>. The changeset must not
442     * be null and id &gt; 0 must be true.
443     *
444     * @param changeset the changeset to update. Must not be null.
445     * @param monitor the progress monitor. If null, uses the {@link NullProgressMonitor#INSTANCE}.
446     *
447     * @throws OsmTransferException if something goes wrong.
448     * @throws IllegalArgumentException if changeset is null
449     * @throws IllegalArgumentException if changeset.getId() &lt;= 0
450     *
451     */
452    public void updateChangeset(Changeset changeset, ProgressMonitor monitor) throws OsmTransferException {
453        CheckParameterUtil.ensureParameterNotNull(changeset, "changeset");
454        if (monitor == null) {
455            monitor = NullProgressMonitor.INSTANCE;
456        }
457        if (changeset.getId() <= 0)
458            throw new IllegalArgumentException(tr("Changeset ID > 0 expected. Got {0}.", changeset.getId()));
459        try {
460            monitor.beginTask(tr("Updating changeset..."));
461            initialize(monitor);
462            monitor.setCustomText(tr("Updating changeset {0}...", changeset.getId()));
463            sendRequest(
464                    "PUT",
465                    "changeset/" + changeset.getId(),
466                    toXml(changeset),
467                    monitor
468            );
469        } catch(ChangesetClosedException e) {
470            e.setSource(ChangesetClosedException.Source.UPDATE_CHANGESET);
471            throw e;
472        } catch(OsmApiException e) {
473            String errorHeader = e.getErrorHeader();
474            if (e.getResponseCode() == HttpURLConnection.HTTP_CONFLICT && ChangesetClosedException.errorHeaderMatchesPattern(errorHeader))
475                throw new ChangesetClosedException(errorHeader, ChangesetClosedException.Source.UPDATE_CHANGESET);
476            throw e;
477        } finally {
478            monitor.finishTask();
479        }
480    }
481
482    /**
483     * Closes a changeset on the server. Sets changeset.setOpen(false) if this operation succeeds.
484     *
485     * @param changeset the changeset to be closed. Must not be null. changeset.getId() &gt; 0 required.
486     * @param monitor the progress monitor. If null, uses {@link NullProgressMonitor#INSTANCE}
487     *
488     * @throws OsmTransferException if something goes wrong.
489     * @throws IllegalArgumentException thrown if changeset is null
490     * @throws IllegalArgumentException thrown if changeset.getId() &lt;= 0
491     */
492    public void closeChangeset(Changeset changeset, ProgressMonitor monitor) throws OsmTransferException {
493        CheckParameterUtil.ensureParameterNotNull(changeset, "changeset");
494        if (monitor == null) {
495            monitor = NullProgressMonitor.INSTANCE;
496        }
497        if (changeset.getId() <= 0)
498            throw new IllegalArgumentException(tr("Changeset ID > 0 expected. Got {0}.", changeset.getId()));
499        try {
500            monitor.beginTask(tr("Closing changeset..."));
501            initialize(monitor);
502            /* send "\r\n" instead of empty string, so we don't send zero payload - works around bugs
503               in proxy software */
504            sendRequest("PUT", "changeset" + "/" + changeset.getId() + "/close", "\r\n", monitor);
505            changeset.setOpen(false);
506        } finally {
507            monitor.finishTask();
508        }
509    }
510
511    /**
512     * Uploads a list of changes in "diff" form to the server.
513     *
514     * @param list the list of changed OSM Primitives
515     * @param  monitor the progress monitor
516     * @return list of processed primitives
517     * @throws OsmTransferException if something is wrong
518     */
519    public Collection<OsmPrimitive> uploadDiff(Collection<? extends OsmPrimitive> list, ProgressMonitor monitor)
520            throws OsmTransferException {
521        try {
522            monitor.beginTask("", list.size() * 2);
523            if (changeset == null)
524                throw new OsmTransferException(tr("No changeset present for diff upload."));
525
526            initialize(monitor);
527
528            // prepare upload request
529            //
530            OsmChangeBuilder changeBuilder = new OsmChangeBuilder(changeset);
531            monitor.subTask(tr("Preparing upload request..."));
532            changeBuilder.start();
533            changeBuilder.append(list);
534            changeBuilder.finish();
535            String diffUploadRequest = changeBuilder.getDocument();
536
537            // Upload to the server
538            //
539            monitor.indeterminateSubTask(
540                    trn("Uploading {0} object...", "Uploading {0} objects...", list.size(), list.size()));
541            String diffUploadResponse = sendRequest("POST", "changeset/" + changeset.getId() + "/upload", diffUploadRequest,monitor);
542
543            // Process the response from the server
544            //
545            DiffResultProcessor reader = new DiffResultProcessor(list);
546            reader.parse(diffUploadResponse, monitor.createSubTaskMonitor(ProgressMonitor.ALL_TICKS, false));
547            return reader.postProcess(
548                    getChangeset(),
549                    monitor.createSubTaskMonitor(ProgressMonitor.ALL_TICKS, false)
550            );
551        } catch(OsmTransferException e) {
552            throw e;
553        } catch(XmlParsingException e) {
554            throw new OsmTransferException(e);
555        } finally {
556            monitor.finishTask();
557        }
558    }
559
560    private void sleepAndListen(int retry, ProgressMonitor monitor) throws OsmTransferCanceledException {
561        Main.info(tr("Waiting 10 seconds ... "));
562        for (int i=0; i < 10; i++) {
563            if (monitor != null) {
564                monitor.setCustomText(tr("Starting retry {0} of {1} in {2} seconds ...", getMaxRetries() - retry,getMaxRetries(), 10-i));
565            }
566            if (cancel)
567                throw new OsmTransferCanceledException();
568            try {
569                Thread.sleep(1000);
570            } catch (InterruptedException ex) {
571                Main.warn("InterruptedException in "+getClass().getSimpleName()+" during sleep");
572            }
573        }
574        Main.info(tr("OK - trying again."));
575    }
576
577    /**
578     * Replies the max. number of retries in case of 5XX errors on the server
579     *
580     * @return the max number of retries
581     */
582    protected int getMaxRetries() {
583        int ret = Main.pref.getInteger("osm-server.max-num-retries", DEFAULT_MAX_NUM_RETRIES);
584        return Math.max(ret,0);
585    }
586
587    /**
588     * Determines if JOSM is configured to access OSM API via OAuth
589     * @return {@code true} if JOSM is configured to access OSM API via OAuth, {@code false} otherwise
590     * @since 6349
591     */
592    public static final boolean isUsingOAuth() {
593        return "oauth".equals(Main.pref.get("osm-server.auth-method", "basic"));
594    }
595
596    protected final String sendRequest(String requestMethod, String urlSuffix,String requestBody, ProgressMonitor monitor)
597            throws OsmTransferException {
598        return sendRequest(requestMethod, urlSuffix, requestBody, monitor, true, false);
599    }
600
601    /**
602     * Generic method for sending requests to the OSM API.
603     *
604     * This method will automatically re-try any requests that are answered with a 5xx
605     * error code, or that resulted in a timeout exception from the TCP layer.
606     *
607     * @param requestMethod The http method used when talking with the server.
608     * @param urlSuffix The suffix to add at the server url, not including the version number,
609     *    but including any object ids (e.g. "/way/1234/history").
610     * @param requestBody the body of the HTTP request, if any.
611     * @param monitor the progress monitor
612     * @param doAuthenticate  set to true, if the request sent to the server shall include authentication
613     * credentials;
614     * @param fastFail true to request a short timeout
615     *
616     * @return the body of the HTTP response, if and only if the response code was "200 OK".
617     * @throws OsmTransferException if the HTTP return code was not 200 (and retries have
618     *    been exhausted), or rewrapping a Java exception.
619     */
620    protected final String sendRequest(String requestMethod, String urlSuffix,String requestBody, ProgressMonitor monitor,
621            boolean doAuthenticate, boolean fastFail) throws OsmTransferException {
622        StringBuilder responseBody = new StringBuilder();
623        int retries = fastFail ? 0 : getMaxRetries();
624
625        while(true) { // the retry loop
626            try {
627                url = new URL(new URL(getBaseUrl()), urlSuffix);
628                Main.info(requestMethod + " " + url + "... ");
629                Main.debug(requestBody);
630                // fix #5369, see http://www.tikalk.com/java/forums/httpurlconnection-disable-keep-alive
631                activeConnection = Utils.openHttpConnection(url, false);
632                activeConnection.setConnectTimeout(fastFail ? 1000 : Main.pref.getInteger("socket.timeout.connect",15)*1000);
633                if (fastFail) {
634                    activeConnection.setReadTimeout(1000);
635                }
636                activeConnection.setRequestMethod(requestMethod);
637                if (doAuthenticate) {
638                    addAuth(activeConnection);
639                }
640
641                if ("PUT".equals(requestMethod) || "POST".equals(requestMethod) || "DELETE".equals(requestMethod)) {
642                    activeConnection.setDoOutput(true);
643                    activeConnection.setRequestProperty("Content-type", "text/xml");
644                    try (OutputStream out = activeConnection.getOutputStream()) {
645                        // It seems that certain bits of the Ruby API are very unhappy upon
646                        // receipt of a PUT/POST message without a Content-length header,
647                        // even if the request has no payload.
648                        // Since Java will not generate a Content-length header unless
649                        // we use the output stream, we create an output stream for PUT/POST
650                        // even if there is no payload.
651                        if (requestBody != null) {
652                            try (BufferedWriter bwr = new BufferedWriter(new OutputStreamWriter(out, StandardCharsets.UTF_8))) {
653                                bwr.write(requestBody);
654                                bwr.flush();
655                            }
656                        }
657                    }
658                }
659
660                activeConnection.connect();
661                Main.info(activeConnection.getResponseMessage());
662                int retCode = activeConnection.getResponseCode();
663
664                if (retCode >= 500) {
665                    if (retries-- > 0) {
666                        sleepAndListen(retries, monitor);
667                        Main.info(tr("Starting retry {0} of {1}.", getMaxRetries() - retries,getMaxRetries()));
668                        continue;
669                    }
670                }
671
672                // populate return fields.
673                responseBody.setLength(0);
674
675                // If the API returned an error code like 403 forbidden, getInputStream
676                // will fail with an IOException.
677                InputStream i = getConnectionStream();
678                if (i != null) {
679                    // the input stream can be null if both the input and the error stream
680                    // are null. Seems to be the case if the OSM server replies a 401
681                    // Unauthorized, see #3887.
682                    //
683                    String s;
684                    try (BufferedReader in = new BufferedReader(new InputStreamReader(i, StandardCharsets.UTF_8))) {
685                        while((s = in.readLine()) != null) {
686                            responseBody.append(s);
687                            responseBody.append("\n");
688                        }
689                    }
690                }
691                String errorHeader = null;
692                // Look for a detailed error message from the server
693                if (activeConnection.getHeaderField("Error") != null) {
694                    errorHeader = activeConnection.getHeaderField("Error");
695                    Main.error("Error header: " + errorHeader);
696                } else if (retCode != HttpURLConnection.HTTP_OK && responseBody.length()>0) {
697                    Main.error("Error body: " + responseBody);
698                }
699                activeConnection.disconnect();
700
701                if (Main.isDebugEnabled()) {
702                    Main.debug("RESPONSE: "+ activeConnection.getHeaderFields());
703                }
704
705                errorHeader = errorHeader == null? null : errorHeader.trim();
706                String errorBody = responseBody.length() == 0? null : responseBody.toString().trim();
707                switch(retCode) {
708                case HttpURLConnection.HTTP_OK:
709                    return responseBody.toString();
710                case HttpURLConnection.HTTP_GONE:
711                    throw new OsmApiPrimitiveGoneException(errorHeader, errorBody);
712                case HttpURLConnection.HTTP_CONFLICT:
713                    if (ChangesetClosedException.errorHeaderMatchesPattern(errorHeader))
714                        throw new ChangesetClosedException(errorBody, ChangesetClosedException.Source.UPLOAD_DATA);
715                    else
716                        throw new OsmApiException(retCode, errorHeader, errorBody);
717                case HttpURLConnection.HTTP_FORBIDDEN:
718                    OsmApiException e = new OsmApiException(retCode, errorHeader, errorBody);
719                    e.setAccessedUrl(activeConnection.getURL().toString());
720                    throw e;
721                default:
722                    throw new OsmApiException(retCode, errorHeader, errorBody);
723                }
724            } catch (SocketTimeoutException | ConnectException e) {
725                if (retries-- > 0) {
726                    continue;
727                }
728                throw new OsmTransferException(e);
729            } catch(IOException e) {
730                throw new OsmTransferException(e);
731            } catch(OsmTransferException e) {
732                throw e;
733            }
734        }
735    }
736
737    private InputStream getConnectionStream() {
738        try {
739            return activeConnection.getInputStream();
740        } catch (IOException ioe) {
741            Main.warn(ioe);
742            return activeConnection.getErrorStream();
743        }
744    }
745
746    /**
747     * Replies the API capabilities.
748     *
749     * @return the API capabilities, or null, if the API is not initialized yet
750     */
751    public synchronized Capabilities getCapabilities() {
752        return capabilities;
753    }
754
755    /**
756     * Ensures that the current changeset can be used for uploading data
757     *
758     * @throws OsmTransferException thrown if the current changeset can't be used for
759     * uploading data
760     */
761    protected void ensureValidChangeset() throws OsmTransferException {
762        if (changeset == null)
763            throw new OsmTransferException(tr("Current changeset is null. Cannot upload data."));
764        if (changeset.getId() <= 0)
765            throw new OsmTransferException(tr("ID of current changeset > 0 required. Current ID is {0}.", changeset.getId()));
766    }
767
768    /**
769     * Replies the changeset data uploads are currently directed to
770     *
771     * @return the changeset data uploads are currently directed to
772     */
773    public Changeset getChangeset() {
774        return changeset;
775    }
776
777    /**
778     * Sets the changesets to which further data uploads are directed. The changeset
779     * can be null. If it isn't null it must have been created, i.e. id &gt; 0 is required. Furthermore,
780     * it must be open.
781     *
782     * @param changeset the changeset
783     * @throws IllegalArgumentException thrown if changeset.getId() &lt;= 0
784     * @throws IllegalArgumentException thrown if !changeset.isOpen()
785     */
786    public void setChangeset(Changeset changeset) {
787        if (changeset == null) {
788            this.changeset = null;
789            return;
790        }
791        if (changeset.getId() <= 0)
792            throw new IllegalArgumentException(tr("Changeset ID > 0 expected. Got {0}.", changeset.getId()));
793        if (!changeset.isOpen())
794            throw new IllegalArgumentException(tr("Open changeset expected. Got closed changeset with id {0}.", changeset.getId()));
795        this.changeset = changeset;
796    }
797
798    private static StringBuilder noteStringBuilder(Note note) {
799        return new StringBuilder().append("notes/").append(note.getId());
800    }
801
802    /**
803     * Create a new note on the server.
804     * @param latlon Location of note
805     * @param text Comment entered by user to open the note
806     * @param monitor Progress monitor
807     * @return Note as it exists on the server after creation (ID assigned)
808     * @throws OsmTransferException
809     */
810    public Note createNote(LatLon latlon, String text, ProgressMonitor monitor) throws OsmTransferException {
811        initialize(monitor);
812        String noteUrl = new StringBuilder()
813            .append("notes?lat=")
814            .append(latlon.lat())
815            .append("&lon=")
816            .append(latlon.lon())
817            .append("&text=")
818            .append(urlEncode(text)).toString();
819
820        String response = sendRequest("POST", noteUrl, null, monitor, true, false);
821        return parseSingleNote(response);
822    }
823
824    /**
825     * Add a comment to an existing note.
826     * @param note The note to add a comment to
827     * @param comment Text of the comment
828     * @param monitor Progress monitor
829     * @return Note returned by the API after the comment was added
830     * @throws OsmTransferException
831     */
832    public Note addCommentToNote(Note note, String comment, ProgressMonitor monitor) throws OsmTransferException {
833        initialize(monitor);
834        String noteUrl = noteStringBuilder(note)
835            .append("/comment?text=")
836            .append(urlEncode(comment)).toString();
837
838        String response = sendRequest("POST", noteUrl, null, monitor, true, false);
839        return parseSingleNote(response);
840    }
841
842    /**
843     * Close a note.
844     * @param note Note to close. Must currently be open
845     * @param closeMessage Optional message supplied by the user when closing the note
846     * @param monitor Progress monitor
847     * @return Note returned by the API after the close operation
848     * @throws OsmTransferException
849     */
850    public Note closeNote(Note note, String closeMessage, ProgressMonitor monitor) throws OsmTransferException {
851        initialize(monitor);
852        String encodedMessage = urlEncode(closeMessage);
853        StringBuilder urlBuilder = noteStringBuilder(note)
854            .append("/close");
855        if (encodedMessage != null && !encodedMessage.trim().isEmpty()) {
856            urlBuilder.append("?text=");
857            urlBuilder.append(encodedMessage);
858        }
859
860        String response = sendRequest("POST", urlBuilder.toString(), null, monitor, true, false);
861        return parseSingleNote(response);
862    }
863
864    /**
865     * Reopen a closed note
866     * @param note Note to reopen. Must currently be closed
867     * @param reactivateMessage Optional message supplied by the user when reopening the note
868     * @param monitor Progress monitor
869     * @return Note returned by the API after the reopen operation
870     * @throws OsmTransferException
871     */
872    public Note reopenNote(Note note, String reactivateMessage, ProgressMonitor monitor) throws OsmTransferException {
873        initialize(monitor);
874        String encodedMessage = urlEncode(reactivateMessage);
875        StringBuilder urlBuilder = noteStringBuilder(note)
876            .append("/reopen");
877        if (encodedMessage != null && !encodedMessage.trim().isEmpty()) {
878            urlBuilder.append("?text=");
879            urlBuilder.append(encodedMessage);
880        }
881
882        String response = sendRequest("POST", urlBuilder.toString(), null, monitor, true, false);
883        return parseSingleNote(response);
884    }
885
886    /** Method for parsing API responses for operations on individual notes */
887    private Note parseSingleNote(String xml) throws OsmTransferException {
888        try {
889            List<Note> newNotes = new NoteReader(xml).parse();
890            if(newNotes.size() == 1) {
891                return newNotes.get(0);
892            }
893            //Shouldn't ever execute. Server will either respond with an error (caught elsewhere) or one note
894            throw new OsmTransferException(tr("Note upload failed"));
895        } catch (SAXException|IOException e) {
896            Main.error(e, true);
897            throw new OsmTransferException(tr("Error parsing note response from server"), e);
898        }
899    }
900
901    /** URL encodes a string. Useful for transforming user input into URL query strings*/
902    private String urlEncode(String string) throws OsmTransferException {
903        try {
904            return URLEncoder.encode(string, "UTF-8");
905        } catch (UnsupportedEncodingException e) {
906            Main.error(e, true);
907            throw new OsmTransferException(tr("Error encoding string: {0}", string), e);
908        }
909    }
910}