Use account index for suggesting accounts if available

When the account index is used for queries, the returned AccountInfo's
for matched accounts always contain the preferred email address of the
account, even if the account was matched by a secondary email address.
As result some suggestions that are shown in the UI may not contain
the query string, which might confuse users. For example if account X
has two emails, 'foo@example.com' (primary) and 'bar@example.com', X
is suggested when the user types 'bar', but the suggestion is
displayed as 'X <foo@example.com>' and not as expected as 'X
<bar@example.com>'. This problem will be addressed by a follow-up
change. The idea is to return all email addresses with AccountInfo and
let the UI find out which email to display in the suggestion. Chosing
the matching email should be straight-forward for the UI since it
already highlights the matched substring and hence it can easily check
which email matches.

Change-Id: Ife5e3acd9abf1981c05467afb59c2166330a87f4
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/account/SuggestAccounts.java

@@ -15,8 +15,10 @@
 package com.google.gerrit.server.account;
 
 import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.extensions.common.AccountInfo;
 import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.MethodNotAllowedException;
 import com.google.gerrit.extensions.restapi.RestReadView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.reviewdb.client.Account;
@@ -24,12 +26,18 @@ import com.google.gerrit.reviewdb.client.AccountExternalId;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.api.accounts.AccountInfoComparator;
 import com.google.gerrit.server.config.GerritServerConfig;
+import com.google.gerrit.server.index.account.AccountIndexCollection;
+import com.google.gerrit.server.query.QueryParseException;
+import com.google.gerrit.server.query.QueryResult;
+import com.google.gerrit.server.query.account.AccountQueryBuilder;
+import com.google.gerrit.server.query.account.AccountQueryProcessor;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 
 import org.eclipse.jgit.lib.Config;
 import org.kohsuke.args4j.Option;
 
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
@@ -43,6 +51,9 @@ public class SuggestAccounts implements RestReadView<TopLevelResource> {
   private final AccountControl accountControl;
   private final AccountLoader accountLoader;
   private final AccountCache accountCache;
+  private final AccountIndexCollection indexes;
+  private final AccountQueryBuilder queryBuilder;
+  private final AccountQueryProcessor queryProcessor;
   private final ReviewDb db;
   private final boolean suggest;
   private final int suggestFrom;
@@ -59,6 +70,7 @@ public class SuggestAccounts implements RestReadView<TopLevelResource> {
     } else {
       limit = Math.min(n, MAX_RESULTS);
     }
+    queryProcessor.setLimit(limit);
   }
 
   @Option(name = "--query", aliases = {"-q"}, metaVar = "QUERY", usage = "match users")
@@ -70,11 +82,17 @@ public class SuggestAccounts implements RestReadView<TopLevelResource> {
   SuggestAccounts(AccountControl.Factory accountControlFactory,
       AccountLoader.Factory accountLoaderFactory,
       AccountCache accountCache,
+      AccountIndexCollection indexes,
+      AccountQueryBuilder queryBuilder,
+      AccountQueryProcessor queryProcessor,
       ReviewDb db,
       @GerritServerConfig Config cfg) {
     accountControl = accountControlFactory.get();
     accountLoader = accountLoaderFactory.create(true);
     this.accountCache = accountCache;
+    this.indexes = indexes;
+    this.queryBuilder = queryBuilder;
+    this.queryProcessor = queryProcessor;
     this.db = db;
     this.suggestFrom = cfg.getInt("suggest", null, "from", 0);
 
@@ -95,7 +113,7 @@ public class SuggestAccounts implements RestReadView<TopLevelResource> {
 
   @Override
   public List<AccountInfo> apply(TopLevelResource rsrc)
-      throws OrmException, BadRequestException {
+      throws OrmException, BadRequestException, MethodNotAllowedException {
     if (Strings.isNullOrEmpty(query)) {
       throw new BadRequestException("missing query field");
     }
@@ -104,6 +122,36 @@ public class SuggestAccounts implements RestReadView<TopLevelResource> {
       return Collections.emptyList();
     }
 
+    Collection<AccountInfo> matches =
+        indexes.getSearchIndex() != null
+            ? queryFromIndex()
+            : queryFromDb();
+    return AccountInfoComparator.ORDER_NULLS_LAST.sortedCopy(matches);
+  }
+
+  public Collection<AccountInfo> queryFromIndex()
+      throws MethodNotAllowedException, OrmException {
+    if (queryProcessor.isDisabled()) {
+      throw new MethodNotAllowedException("query disabled");
+    }
+
+    Map<Account.Id, AccountInfo> matches = new LinkedHashMap<>();
+    try {
+      QueryResult<AccountState> result =
+          queryProcessor.query(queryBuilder.defaultField(query));
+      for (AccountState accountState : result.entities()) {
+        Account.Id id = accountState.getAccount().getId();
+        matches.put(id, accountLoader.get(id));
+      }
+    } catch (QueryParseException e) {
+      return ImmutableSet.of();
+    }
+
+    accountLoader.fill();
+    return matches.values();
+  }
+
+  public Collection<AccountInfo> queryFromDb() throws OrmException {
     String a = query;
     String b = a + MAX_SUFFIX;
 
@@ -136,7 +184,7 @@ public class SuggestAccounts implements RestReadView<TopLevelResource> {
       }
     }
 
-    return AccountInfoComparator.ORDER_NULLS_LAST.sortedCopy(matches.values());
+    return matches.values();
   }
 
   private boolean addSuggestion(Map<Account.Id, AccountInfo> map, Account a) {

gerrit-server/src/main/java/com/google/gerrit/server/query/account/AccountQueryBuilder.java

@@ -123,7 +123,7 @@ public class AccountQueryBuilder extends QueryBuilder<AccountState> {
   }
 
   @Override
-  protected Predicate<AccountState> defaultField(String query)
+  public Predicate<AccountState> defaultField(String query)
       throws QueryParseException {
     if ("self".equalsIgnoreCase(query)) {
       return AccountPredicates.id(self());