Java tutorial
// Copyright (C) 2017 The Android Open Source Project // // 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 com.google.gerrit.server.account.externalids; import static org.eclipse.jgit.lib.Constants.OBJ_BLOB; import com.google.common.annotations.VisibleForTesting; import com.google.common.collect.ImmutableSet; import com.google.gerrit.common.Nullable; import com.google.gerrit.metrics.Description; import com.google.gerrit.metrics.Description.Units; import com.google.gerrit.metrics.MetricMaker; import com.google.gerrit.metrics.Timer0; import com.google.gerrit.reviewdb.client.RefNames; import com.google.gerrit.reviewdb.server.ReviewDb; import com.google.gerrit.server.config.AllUsersName; import com.google.gerrit.server.config.GerritServerConfig; import com.google.gerrit.server.git.GitRepositoryManager; import com.google.gwtorm.server.OrmException; import com.google.inject.Inject; import com.google.inject.Singleton; import java.io.IOException; import java.util.HashSet; import java.util.Set; import org.eclipse.jgit.errors.ConfigInvalidException; import org.eclipse.jgit.lib.Config; import org.eclipse.jgit.lib.ObjectId; import org.eclipse.jgit.lib.Ref; import org.eclipse.jgit.lib.Repository; import org.eclipse.jgit.notes.Note; import org.eclipse.jgit.notes.NoteMap; import org.eclipse.jgit.revwalk.RevWalk; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Class to read external IDs from ReviewDb or NoteDb. * * <p>In NoteDb external IDs are stored in the All-Users repository in a Git Notes branch called * refs/meta/external-ids where the sha1 of the external ID is used as note name. Each note content * is a git config file that contains an external ID. It has exactly one externalId subsection with * an accountId and optionally email and password: * * <pre> * [externalId "username:jdoe"] * accountId = 1003407 * email = jdoe@example.com * password = bcrypt:4:LCbmSBDivK/hhGVQMfkDpA==:XcWn0pKYSVU/UJgOvhidkEtmqCp6oKB7 * </pre> */ @Singleton public class ExternalIdReader { private static final Logger log = LoggerFactory.getLogger(ExternalIdReader.class); public static final int MAX_NOTE_SZ = 1 << 19; public static ObjectId readRevision(Repository repo) throws IOException { Ref ref = repo.exactRef(RefNames.REFS_EXTERNAL_IDS); return ref != null ? ref.getObjectId() : ObjectId.zeroId(); } public static NoteMap readNoteMap(RevWalk rw, ObjectId rev) throws IOException { if (!rev.equals(ObjectId.zeroId())) { return NoteMap.read(rw.getObjectReader(), rw.parseCommit(rev)); } return NoteMap.newEmptyMap(); } private final boolean readFromGit; private final GitRepositoryManager repoManager; private final AllUsersName allUsersName; private boolean failOnLoad = false; private final Timer0 readAllLatency; @Inject ExternalIdReader(@GerritServerConfig Config cfg, GitRepositoryManager repoManager, AllUsersName allUsersName, MetricMaker metricMaker) { this.readFromGit = cfg.getBoolean("user", null, "readExternalIdsFromGit", false); this.repoManager = repoManager; this.allUsersName = allUsersName; this.readAllLatency = metricMaker.newTimer("notedb/read_all_external_ids_latency", new Description("Latency for reading all external IDs from NoteDb.").setCumulative() .setUnit(Units.MILLISECONDS)); } @VisibleForTesting public void setFailOnLoad(boolean failOnLoad) { this.failOnLoad = failOnLoad; } boolean readFromGit() { return readFromGit; } ObjectId readRevision() throws IOException { try (Repository repo = repoManager.openRepository(allUsersName)) { return readRevision(repo); } } /** Reads and returns all external IDs. */ Set<ExternalId> all(ReviewDb db) throws IOException, OrmException { checkReadEnabled(); if (readFromGit) { try (Repository repo = repoManager.openRepository(allUsersName)) { return all(repo, readRevision(repo)); } } return ExternalId.from(db.accountExternalIds().all().toList()); } /** * Reads and returns all external IDs from the specified revision of the refs/meta/external-ids * branch. */ Set<ExternalId> all(ObjectId rev) throws IOException { checkReadEnabled(); try (Repository repo = repoManager.openRepository(allUsersName)) { return all(repo, rev); } } /** Reads and returns all external IDs. */ private Set<ExternalId> all(Repository repo, ObjectId rev) throws IOException { if (rev.equals(ObjectId.zeroId())) { return ImmutableSet.of(); } try (Timer0.Context ctx = readAllLatency.start(); RevWalk rw = new RevWalk(repo)) { NoteMap noteMap = readNoteMap(rw, rev); Set<ExternalId> extIds = new HashSet<>(); for (Note note : noteMap) { byte[] raw = rw.getObjectReader().open(note.getData(), OBJ_BLOB).getCachedBytes(MAX_NOTE_SZ); try { extIds.add(ExternalId.parse(note.getName(), raw)); } catch (Exception e) { log.error(String.format("Ignoring invalid external ID note %s", note.getName()), e); } } return extIds; } } /** Reads and returns the specified external ID. */ @Nullable ExternalId get(ReviewDb db, ExternalId.Key key) throws IOException, ConfigInvalidException, OrmException { checkReadEnabled(); if (readFromGit) { try (Repository repo = repoManager.openRepository(allUsersName); RevWalk rw = new RevWalk(repo)) { ObjectId rev = readRevision(repo); if (rev.equals(ObjectId.zeroId())) { return null; } return parse(key, rw, rev); } } return ExternalId.from(db.accountExternalIds().get(key.asAccountExternalIdKey())); } /** Reads and returns the specified external ID from the given revision. */ @Nullable ExternalId get(ExternalId.Key key, ObjectId rev) throws IOException, ConfigInvalidException { checkReadEnabled(); if (rev.equals(ObjectId.zeroId())) { return null; } try (Repository repo = repoManager.openRepository(allUsersName); RevWalk rw = new RevWalk(repo)) { return parse(key, rw, rev); } } private static ExternalId parse(ExternalId.Key key, RevWalk rw, ObjectId rev) throws IOException, ConfigInvalidException { NoteMap noteMap = readNoteMap(rw, rev); ObjectId noteId = key.sha1(); if (!noteMap.contains(noteId)) { return null; } byte[] raw = rw.getObjectReader().open(noteMap.get(noteId), OBJ_BLOB).getCachedBytes(MAX_NOTE_SZ); return ExternalId.parse(noteId.name(), raw); } private void checkReadEnabled() throws IOException { if (failOnLoad) { throw new IOException("Reading from external IDs is disabled"); } } }