Java tutorial
/** * JBoss, Home of Professional Open Source Copyright Red Hat, Inc., and individual contributors * * Licensed 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.jboss.aerogear.simplepush.server.datastore; import java.net.MalformedURLException; import java.nio.charset.Charset; import java.util.Collection; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; import java.util.Set; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.node.ObjectNode; import org.ektorp.BulkDeleteDocument; import org.ektorp.ViewQuery; import org.ektorp.ViewResult; import org.ektorp.ViewResult.Row; import org.ektorp.http.HttpClient; import org.ektorp.http.StdHttpClient; import org.ektorp.impl.StdCouchDbConnector; import org.ektorp.impl.StdCouchDbInstance; import org.ektorp.support.DesignDocument; import org.ektorp.support.DesignDocument.View; import org.jboss.aerogear.simplepush.protocol.Ack; import org.jboss.aerogear.simplepush.protocol.impl.AckImpl; import org.jboss.aerogear.simplepush.server.Channel; import org.jboss.aerogear.simplepush.server.DefaultChannel; /** * DataStore that uses a CouchDB database for storage. */ public class CouchDBDataStore implements DataStore { private static final String UAID_FIELD = "uaid"; private static final String TYPE_FIELD = "type"; private static final String TOKEN_FIELD = "token"; private static final String CHID_FIELD = "chid"; private static final String VERSION_FIELD = "version"; private static final String DOC_FIELD = "doc"; private final HttpClient httpClient; private final StdCouchDbInstance stdCouchDbInstance; private final StdCouchDbConnector db; private final DesignDocument designDocument; private final static Charset UTF_8 = Charset.forName("UTF-8"); public CouchDBDataStore(final String url, final String dbName) { try { httpClient = new StdHttpClient.Builder().url(url).build(); } catch (final MalformedURLException e) { throw new IllegalStateException(e); } stdCouchDbInstance = new StdCouchDbInstance(httpClient); db = new StdCouchDbConnector(dbName, stdCouchDbInstance); db.createDatabaseIfNotExists(); designDocument = new DesignDocument("_design/channels"); addView(designDocument, Views.CHANNEL); addView(designDocument, Views.UAID); addView(designDocument, Views.TOKEN); addView(designDocument, Views.UNACKS); addView(designDocument, Views.SERVER); if (!db.contains(designDocument.getId())) { db.create(designDocument); } } private void addView(final DesignDocument doc, final Views view) { if (!doc.containsView(view.viewName())) { doc.addView(view.viewName(), new View(view.mapFunction())); } } @Override public void savePrivateKeySalt(final byte[] salt) { final byte[] privateKeySalt = getPrivateKeySalt(); if (privateKeySalt.length == 0) { final Map<String, String> map = new HashMap<String, String>(2); map.put(TYPE_FIELD, Views.SERVER.viewName()); map.put("salt", new String(salt, UTF_8)); db.create(map); } } @Override public byte[] getPrivateKeySalt() { final ViewQuery viewQuery = new ViewQuery().dbPath(db.path()).viewName(Views.SERVER.viewName()) .designDocId(designDocument.getId()); final ViewResult viewResult = db.queryView(viewQuery); if (viewResult.isEmpty()) { return new byte[] {}; } final Row row = viewResult.getRows().get(0); return row.getKeyAsNode().get("salt").asText().getBytes(UTF_8); } @Override public boolean saveChannel(final Channel channel) { db.create(channelAsMap(channel)); return true; } private Map<String, String> channelAsMap(final Channel channel) { final Map<String, String> map = new HashMap<String, String>(5); map.put(UAID_FIELD, channel.getUAID()); map.put(TYPE_FIELD, Views.CHANNEL.viewName()); map.put(TOKEN_FIELD, channel.getEndpointToken()); map.put(CHID_FIELD, channel.getChannelId()); map.put(VERSION_FIELD, Long.toString(channel.getVersion())); return map; } @Override public Channel getChannel(final String channelId) throws ChannelNotFoundException { return channelFromJson(getChannelJson(channelId)); } private JsonNode getChannelJson(final String channelId) throws ChannelNotFoundException { final ViewResult viewResult = db.queryView(query(Views.CHANNEL.viewName(), channelId)); final List<Row> rows = viewResult.getRows(); if (rows.isEmpty()) { throw new ChannelNotFoundException("Cound not find channel", channelId); } if (rows.size() > 1) { throw new IllegalStateException("There should not be multiple channelId with the same id"); } return rows.get(0).getValueAsNode(); } private Channel channelFromJson(final JsonNode node) { final JsonNode doc = node.get("doc"); return new DefaultChannel(doc.get(UAID_FIELD).asText(), doc.get(CHID_FIELD).asText(), doc.get(VERSION_FIELD).asLong(), doc.get(TOKEN_FIELD).asText()); } @Override public void removeChannels(final String uaid) { final ViewResult viewResult = db.queryView(query(Views.UAID.viewName(), uaid)); final List<Row> rows = viewResult.getRows(); final Set<String> channelIds = new HashSet<String>(rows.size()); for (Row row : rows) { final JsonNode json = row.getValueAsNode().get(DOC_FIELD); channelIds.add(json.get(CHID_FIELD).asText()); } removeChannels(channelIds); } private ViewQuery query(final String viewName, final String key) { return new ViewQuery().dbPath(db.path()).viewName(viewName).designDocId(designDocument.getId()).key(key); } @Override public void removeChannels(final Set<String> channelIds) { final ViewResult viewResult = db.queryView(channelsQuery(channelIds)); final List<Row> rows = viewResult.getRows(); final Collection<BulkDeleteDocument> removals = new LinkedHashSet<BulkDeleteDocument>(); for (Row row : rows) { final JsonNode json = row.getValueAsNode(); removals.add(BulkDeleteDocument.of(json.get(DOC_FIELD))); } db.executeBulk(removals); } private ViewQuery channelsQuery(final Set<String> keys) { return new ViewQuery().dbPath(db.path()).viewName(Views.CHANNEL.viewName()) .designDocId(designDocument.getId()).keys(keys); } @Override public Set<String> getChannelIds(final String uaid) { final ViewResult viewResult = db.queryView(query(Views.UAID.viewName(), uaid)); final List<Row> rows = viewResult.getRows(); if (rows.isEmpty()) { return Collections.emptySet(); } final Set<String> channelIds = new HashSet<String>(rows.size()); for (Row row : rows) { channelIds.add(row.getValueAsNode().get(DOC_FIELD).get(CHID_FIELD).asText()); } return channelIds; } @Override public String updateVersion(final String endpointToken, final long version) throws VersionException, ChannelNotFoundException { final ViewResult viewResult = db.queryView(query(Views.TOKEN.viewName(), endpointToken)); final List<Row> rows = viewResult.getRows(); if (rows.isEmpty()) { throw new ChannelNotFoundException("Cound not find channel for endpointToken", endpointToken); } final ObjectNode node = (ObjectNode) rows.get(0).getValueAsNode().get(DOC_FIELD); final long currentVersion = node.get(VERSION_FIELD).asLong(); if (version <= currentVersion) { throw new VersionException( "version [" + version + "] must be greater than the current version [" + currentVersion + "]"); } node.put(VERSION_FIELD, String.valueOf(version)); db.update(node); return node.get(CHID_FIELD).asText(); } @Override public String saveUnacknowledged(final String channelId, final long version) throws ChannelNotFoundException { final JsonNode json = getChannelJson(channelId); final Map<String, String> unack = docToAckMap((ObjectNode) json.get(DOC_FIELD), version); db.create(unack); return unack.get(UAID_FIELD); } private Map<String, String> docToAckMap(final ObjectNode doc, final long version) { final String uaid = doc.get(UAID_FIELD).asText(); final String chid = doc.get(CHID_FIELD).asText(); final String token = doc.get(TOKEN_FIELD).asText(); final Map<String, String> map = new HashMap<String, String>(5); map.put(UAID_FIELD, uaid); map.put(TYPE_FIELD, "ack"); map.put(TOKEN_FIELD, token); map.put(CHID_FIELD, chid); map.put(VERSION_FIELD, Long.toString(version)); return map; } @Override public Set<Ack> getUnacknowledged(final String uaid) { final ViewResult viewResult = db.queryView(query(Views.UNACKS.viewName(), uaid)); return rowsToAcks(viewResult.getRows()); } @Override public Set<Ack> removeAcknowledged(final String uaid, final Set<Ack> acked) { final ViewResult viewResult = db.queryView(query(Views.UNACKS.viewName(), uaid)); final List<Row> rows = viewResult.getRows(); final Collection<BulkDeleteDocument> removals = new LinkedHashSet<BulkDeleteDocument>(); for (Iterator<Row> iter = rows.iterator(); iter.hasNext();) { final Row row = iter.next(); final JsonNode json = row.getValueAsNode(); final JsonNode doc = json.get(DOC_FIELD); final String channelId = doc.get(CHID_FIELD).asText(); for (Ack ack : acked) { if (ack.getChannelId().equals(channelId)) { removals.add(BulkDeleteDocument.of(doc)); iter.remove(); } } } db.executeBulk(removals); return rowsToAcks(rows); } private Set<Ack> rowsToAcks(final List<Row> rows) { if (rows.isEmpty()) { return Collections.emptySet(); } final Set<Ack> unacks = new HashSet<Ack>(rows.size()); for (Row row : rows) { final JsonNode json = row.getValueAsNode().get(DOC_FIELD); unacks.add(new AckImpl(json.get(CHID_FIELD).asText(), json.get(VERSION_FIELD).asLong())); } return unacks; } }