gerrit.PRED_current_user_2 Maven / Gradle / Ivy
// Copyright (C) 2011 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 gerrit;
import static com.googlecode.prolog_cafe.lang.SymbolTerm.intern;
import com.google.gerrit.reviewdb.client.Account;
import com.google.gerrit.rules.PrologEnvironment;
import com.google.gerrit.rules.StoredValues;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.IdentifiedUser;
import com.googlecode.prolog_cafe.exceptions.IllegalTypeException;
import com.googlecode.prolog_cafe.exceptions.PInstantiationException;
import com.googlecode.prolog_cafe.exceptions.PrologException;
import com.googlecode.prolog_cafe.lang.IntegerTerm;
import com.googlecode.prolog_cafe.lang.JavaObjectTerm;
import com.googlecode.prolog_cafe.lang.Operation;
import com.googlecode.prolog_cafe.lang.Predicate;
import com.googlecode.prolog_cafe.lang.Prolog;
import com.googlecode.prolog_cafe.lang.StructureTerm;
import com.googlecode.prolog_cafe.lang.SymbolTerm;
import com.googlecode.prolog_cafe.lang.Term;
import com.googlecode.prolog_cafe.lang.VariableTerm;
import java.util.Map;
/**
* Loads a CurrentUser object for a user identity.
*
* Values are cached in the hash {@code current_user}, avoiding recreation during a single
* evaluation.
*
*
* current_user(user(+AccountId), -CurrentUser).
*
*/
class PRED_current_user_2 extends Predicate.P2 {
private static final SymbolTerm user = intern("user", 1);
private static final SymbolTerm anonymous = intern("anonymous");
PRED_current_user_2(Term a1, Term a2, Operation n) {
arg1 = a1;
arg2 = a2;
cont = n;
}
@Override
public Operation exec(Prolog engine) throws PrologException {
engine.setB0();
Term a1 = arg1.dereference();
Term a2 = arg2.dereference();
if (a1 instanceof VariableTerm) {
throw new PInstantiationException(this, 1);
}
if (!a2.unify(createUser(engine, a1), engine.trail)) {
return engine.fail();
}
return cont;
}
public Term createUser(Prolog engine, Term key) {
if (!(key instanceof StructureTerm)
|| key.arity() != 1
|| !((StructureTerm) key).functor().equals(user)) {
throw new IllegalTypeException(this, 1, "user(int)", key);
}
Term idTerm = key.arg(0);
CurrentUser user;
if (idTerm instanceof IntegerTerm) {
Map cache = StoredValues.USERS.get(engine);
Account.Id accountId = new Account.Id(((IntegerTerm) idTerm).intValue());
user = cache.get(accountId);
if (user == null) {
IdentifiedUser.GenericFactory userFactory = userFactory(engine);
IdentifiedUser who = userFactory.create(accountId);
cache.put(accountId, who);
user = who;
}
} else if (idTerm.equals(anonymous)) {
user = StoredValues.ANONYMOUS_USER.get(engine);
} else {
throw new IllegalTypeException(this, 1, "user(int)", key);
}
return new JavaObjectTerm(user);
}
private static IdentifiedUser.GenericFactory userFactory(Prolog engine) {
return ((PrologEnvironment) engine.control).getArgs().getUserFactory();
}
}