java/com/google/gerrit/server/change/ChangeFinder.java - gerrit - Git at Google

 // Copyright (C) 2016 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.change;

 import com.google.common.base.Throwables;
 import com.google.common.cache.Cache;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
 import com.google.common.primitives.Ints;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.git.ObjectIds;
 import com.google.gerrit.index.IndexConfig;
 import com.google.gerrit.metrics.Counter1;
 import com.google.gerrit.metrics.Description;
 import com.google.gerrit.metrics.Field;
 import com.google.gerrit.metrics.MetricMaker;
 import com.google.gerrit.server.cache.CacheModule;
 import com.google.gerrit.server.logging.Metadata;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.project.NoSuchChangeException;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.gerrit.server.query.change.InternalChangeQuery;
 import com.google.inject.Inject;
 import com.google.inject.Module;
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import com.google.inject.name.Named;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 import java.util.Set;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;

 @Singleton
 public class ChangeFinder {
   private static final String CACHE_NAME = "changeid_project";

   public static Module module() {
     return new CacheModule() {
       @Override
       protected void configure() {
         cache(CACHE_NAME, Change.Id.class, String.class).maximumWeight(1024);
       }
     };
   }

   public enum ChangeIdType {
     ALL,
     TRIPLET,
     NUMERIC_ID,
     I_HASH,
     PROJECT_NUMERIC_ID,
     COMMIT_HASH
   }

   private final IndexConfig indexConfig;
   private final Cache<Change.Id, String> changeIdProjectCache;
   private final Provider<InternalChangeQuery> queryProvider;
   private final ChangeNotes.Factory changeNotesFactory;
   private final Counter1<ChangeIdType> changeIdCounter;

   @Inject
   ChangeFinder(
       IndexConfig indexConfig,
       @Named(CACHE_NAME) Cache<Change.Id, String> changeIdProjectCache,
       Provider<InternalChangeQuery> queryProvider,
       ChangeNotes.Factory changeNotesFactory,
       MetricMaker metricMaker) {
     this.indexConfig = indexConfig;
     this.changeIdProjectCache = changeIdProjectCache;
     this.queryProvider = queryProvider;
     this.changeNotesFactory = changeNotesFactory;
     this.changeIdCounter =
         metricMaker.newCounter(
             "http/server/rest_api/change_id_type",
             new Description("Total number of API calls per identifier type.")
                 .setRate()
                 .setUnit("requests"),
             Field.ofEnum(ChangeIdType.class, "change_id_type", Metadata.Builder::changeIdType)
                 .build());
   }

   public ChangeNotes findOne(String id) {
     List<ChangeNotes> ctls = find(id);
     if (ctls.size() != 1) {
       return null;
     }
     return ctls.get(0);
   }

   /**
    * Find changes matching the given identifier.
    *
    * @param id change identifier.
    * @return possibly-empty list of notes for all matching changes; may or may not be visible.
    */
   public List<ChangeNotes> find(String id) {
     if (id.isEmpty()) {
       return Collections.emptyList();
     }

     int z = id.lastIndexOf('~');
     int y = id.lastIndexOf('~', z - 1);
     if (y < 0 && z > 0) {
       // Try project~numericChangeId
       Integer n = Ints.tryParse(id.substring(z + 1));
       if (n != null) {
         changeIdCounter.increment(ChangeIdType.PROJECT_NUMERIC_ID);
         return fromProjectNumber(id.substring(0, z), n.intValue());
       }
     }

     if (y < 0 && z < 0) {
       // Try numeric changeId
       Integer n = Ints.tryParse(id);
       if (n != null) {
         changeIdCounter.increment(ChangeIdType.NUMERIC_ID);
         return find(Change.id(n));
       }
     }

     // Use the index to search for changes, but don't return any stored fields,
     // to force rereading in case the index is stale.
     InternalChangeQuery query = queryProvider.get().noFields();

     // Try commit hash
     if (id.matches("^([0-9a-fA-F]{" + ObjectIds.ABBREV_STR_LEN + "," + ObjectIds.STR_LEN + "})$")) {
       changeIdCounter.increment(ChangeIdType.COMMIT_HASH);
       return asChangeNotes(query.byCommit(id));
     }

     if (y > 0 && z > 0) {
       // Try change triplet (project~branch~Ihash...)
       Optional<ChangeTriplet> triplet = ChangeTriplet.parse(id, y, z);
       if (triplet.isPresent()) {
         ChangeTriplet t = triplet.get();
         changeIdCounter.increment(ChangeIdType.TRIPLET);
         return asChangeNotes(query.byBranchKey(t.branch(), t.id()));
       }
     }

     // Try isolated Ihash... format ("Change-Id: Ihash").
     List<ChangeNotes> notes = asChangeNotes(query.byKeyPrefix(id));
     if (!notes.isEmpty()) {
       changeIdCounter.increment(ChangeIdType.I_HASH);
     }
     return notes;
   }

   private List<ChangeNotes> fromProjectNumber(String project, int changeNumber) {
     Change.Id cId = Change.id(changeNumber);
     try {
       return ImmutableList.of(
           changeNotesFactory.createChecked(Project.NameKey.parse(project), cId));
     } catch (NoSuchChangeException e) {
       return Collections.emptyList();
     } catch (StorageException e) {
       // Distinguish between a RepositoryNotFoundException (project argument invalid) and
       // other StorageExceptions (failure in the persistence layer).
       if (Throwables.getRootCause(e) instanceof RepositoryNotFoundException) {
         return Collections.emptyList();
       }
       throw e;
     }
   }

   public ChangeNotes findOne(Change.Id id) {
     List<ChangeNotes> notes = find(id);
     if (notes.size() != 1) {
       throw new NoSuchChangeException(id);
     }
     return notes.get(0);
   }

   public List<ChangeNotes> find(Change.Id id) {
     String project = changeIdProjectCache.getIfPresent(id);
     if (project != null) {
       return fromProjectNumber(project, id.get());
     }

     // Use the index to search for changes, but don't return any stored fields,
     // to force rereading in case the index is stale.
     InternalChangeQuery query = queryProvider.get().noFields();
     List<ChangeData> r = query.byLegacyChangeId(id);
     if (r.size() == 1) {
       changeIdProjectCache.put(id, Url.encode(r.get(0).project().get()));
     }
     return asChangeNotes(r);
   }

   private List<ChangeNotes> asChangeNotes(List<ChangeData> cds) {
     List<ChangeNotes> notes = new ArrayList<>(cds.size());
     if (!indexConfig.separateChangeSubIndexes()) {
       for (ChangeData cd : cds) {
         notes.add(cd.notes());
       }
       return notes;
     }

     // If an index implementation uses separate non-atomic subindexes, it's possible to temporarily
     // observe a change as present in both subindexes, if this search is concurrent with a write.
     // Dedup to avoid confusing the caller. We can choose an arbitrary ChangeData instance because
     // the index results have no stored fields, so the data is already reloaded. (It's also possible
     // that a change might appear in zero subindexes, but there's nothing we can do here to help
     // this case.)
     Set<Change.Id> seen = Sets.newHashSetWithExpectedSize(cds.size());
     for (ChangeData cd : cds) {
       if (seen.add(cd.getId())) {
         notes.add(cd.notes());
       }
     }
     return notes;
   }
 }
	// Copyright (C) 2016 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.change;

	import com.google.common.base.Throwables;
	import com.google.common.cache.Cache;
	import com.google.common.collect.ImmutableList;
	import com.google.common.collect.Sets;
	import com.google.common.primitives.Ints;
	import com.google.gerrit.entities.Change;
	import com.google.gerrit.entities.Project;
	import com.google.gerrit.exceptions.StorageException;
	import com.google.gerrit.extensions.restapi.Url;
	import com.google.gerrit.git.ObjectIds;
	import com.google.gerrit.index.IndexConfig;
	import com.google.gerrit.metrics.Counter1;
	import com.google.gerrit.metrics.Description;
	import com.google.gerrit.metrics.Field;
	import com.google.gerrit.metrics.MetricMaker;
	import com.google.gerrit.server.cache.CacheModule;
	import com.google.gerrit.server.logging.Metadata;
	import com.google.gerrit.server.notedb.ChangeNotes;
	import com.google.gerrit.server.project.NoSuchChangeException;
	import com.google.gerrit.server.query.change.ChangeData;
	import com.google.gerrit.server.query.change.InternalChangeQuery;
	import com.google.inject.Inject;
	import com.google.inject.Module;
	import com.google.inject.Provider;
	import com.google.inject.Singleton;
	import com.google.inject.name.Named;
	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.List;
	import java.util.Optional;
	import java.util.Set;
	import org.eclipse.jgit.errors.RepositoryNotFoundException;

	@Singleton
	public class ChangeFinder {
	private static final String CACHE_NAME = "changeid_project";

	public static Module module() {
	return new CacheModule() {
	@Override
	protected void configure() {
	cache(CACHE_NAME, Change.Id.class, String.class).maximumWeight(1024);
	}
	};
	}

	public enum ChangeIdType {
	ALL,
	TRIPLET,
	NUMERIC_ID,
	I_HASH,
	PROJECT_NUMERIC_ID,
	COMMIT_HASH
	}

	private final IndexConfig indexConfig;
	private final Cache<Change.Id, String> changeIdProjectCache;
	private final Provider<InternalChangeQuery> queryProvider;
	private final ChangeNotes.Factory changeNotesFactory;
	private final Counter1<ChangeIdType> changeIdCounter;

	@Inject
	ChangeFinder(
	IndexConfig indexConfig,
	@Named(CACHE_NAME) Cache<Change.Id, String> changeIdProjectCache,
	Provider<InternalChangeQuery> queryProvider,
	ChangeNotes.Factory changeNotesFactory,
	MetricMaker metricMaker) {
	this.indexConfig = indexConfig;
	this.changeIdProjectCache = changeIdProjectCache;
	this.queryProvider = queryProvider;
	this.changeNotesFactory = changeNotesFactory;
	this.changeIdCounter =
	metricMaker.newCounter(
	"http/server/rest_api/change_id_type",
	new Description("Total number of API calls per identifier type.")
	.setRate()
	.setUnit("requests"),
	Field.ofEnum(ChangeIdType.class, "change_id_type", Metadata.Builder::changeIdType)
	.build());
	}

	public ChangeNotes findOne(String id) {
	List<ChangeNotes> ctls = find(id);
	if (ctls.size() != 1) {
	return null;
	}
	return ctls.get(0);
	}

	/**
	* Find changes matching the given identifier.
	*
	* @param id change identifier.
	* @return possibly-empty list of notes for all matching changes; may or may not be visible.
	*/
	public List<ChangeNotes> find(String id) {
	if (id.isEmpty()) {
	return Collections.emptyList();
	}

	int z = id.lastIndexOf('~');
	int y = id.lastIndexOf('~', z - 1);
	if (y < 0 && z > 0) {
	// Try project~numericChangeId
	Integer n = Ints.tryParse(id.substring(z + 1));
	if (n != null) {
	changeIdCounter.increment(ChangeIdType.PROJECT_NUMERIC_ID);
	return fromProjectNumber(id.substring(0, z), n.intValue());
	}
	}

	if (y < 0 && z < 0) {
	// Try numeric changeId
	Integer n = Ints.tryParse(id);
	if (n != null) {
	changeIdCounter.increment(ChangeIdType.NUMERIC_ID);
	return find(Change.id(n));
	}
	}

	// Use the index to search for changes, but don't return any stored fields,
	// to force rereading in case the index is stale.
	InternalChangeQuery query = queryProvider.get().noFields();

	// Try commit hash
	if (id.matches("^([0-9a-fA-F]{" + ObjectIds.ABBREV_STR_LEN + "," + ObjectIds.STR_LEN + "})$")) {
	changeIdCounter.increment(ChangeIdType.COMMIT_HASH);
	return asChangeNotes(query.byCommit(id));
	}

	if (y > 0 && z > 0) {
	// Try change triplet (project~branch~Ihash...)
	Optional<ChangeTriplet> triplet = ChangeTriplet.parse(id, y, z);
	if (triplet.isPresent()) {
	ChangeTriplet t = triplet.get();
	changeIdCounter.increment(ChangeIdType.TRIPLET);
	return asChangeNotes(query.byBranchKey(t.branch(), t.id()));
	}
	}

	// Try isolated Ihash... format ("Change-Id: Ihash").
	List<ChangeNotes> notes = asChangeNotes(query.byKeyPrefix(id));
	if (!notes.isEmpty()) {
	changeIdCounter.increment(ChangeIdType.I_HASH);
	}
	return notes;
	}

	private List<ChangeNotes> fromProjectNumber(String project, int changeNumber) {
	Change.Id cId = Change.id(changeNumber);
	try {
	return ImmutableList.of(
	changeNotesFactory.createChecked(Project.NameKey.parse(project), cId));
	} catch (NoSuchChangeException e) {
	return Collections.emptyList();
	} catch (StorageException e) {
	// Distinguish between a RepositoryNotFoundException (project argument invalid) and
	// other StorageExceptions (failure in the persistence layer).
	if (Throwables.getRootCause(e) instanceof RepositoryNotFoundException) {
	return Collections.emptyList();
	}
	throw e;
	}
	}

	public ChangeNotes findOne(Change.Id id) {
	List<ChangeNotes> notes = find(id);
	if (notes.size() != 1) {
	throw new NoSuchChangeException(id);
	}
	return notes.get(0);
	}

	public List<ChangeNotes> find(Change.Id id) {
	String project = changeIdProjectCache.getIfPresent(id);
	if (project != null) {
	return fromProjectNumber(project, id.get());
	}

	// Use the index to search for changes, but don't return any stored fields,
	// to force rereading in case the index is stale.
	InternalChangeQuery query = queryProvider.get().noFields();
	List<ChangeData> r = query.byLegacyChangeId(id);
	if (r.size() == 1) {
	changeIdProjectCache.put(id, Url.encode(r.get(0).project().get()));
	}
	return asChangeNotes(r);
	}

	private List<ChangeNotes> asChangeNotes(List<ChangeData> cds) {
	List<ChangeNotes> notes = new ArrayList<>(cds.size());
	if (!indexConfig.separateChangeSubIndexes()) {
	for (ChangeData cd : cds) {
	notes.add(cd.notes());
	}
	return notes;
	}

	// If an index implementation uses separate non-atomic subindexes, it's possible to temporarily
	// observe a change as present in both subindexes, if this search is concurrent with a write.
	// Dedup to avoid confusing the caller. We can choose an arbitrary ChangeData instance because
	// the index results have no stored fields, so the data is already reloaded. (It's also possible
	// that a change might appear in zero subindexes, but there's nothing we can do here to help
	// this case.)
	Set<Change.Id> seen = Sets.newHashSetWithExpectedSize(cds.size());
	for (ChangeData cd : cds) {
	if (seen.add(cd.getId())) {
	notes.add(cd.notes());
	}
	}
	return notes;
	}
	}