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// 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.
couchTests.delayed_commits = function(debug) {
var db = new CouchDB("test_suite_db");
db.deleteDb();
db.createDb();
if (debug) debugger;
// By default, couchdb doesn't fully commit documents to disk right away,
// it waits about a second to batch the full commit flush along with any
// other updates. If it crashes or is restarted you may lose the most
// recent commits.
T(db.save({_id:"1",a:2,b:4}).ok);
T(db.open("1") != null);
restartServer();
T(db.open("1") == null); // lost the update.
// note if we waited > 1 sec before the restart, the doc would likely
// commit.
// Retry the same thing but with full commits on.
var db2 = new CouchDB("test_suite_db", {"X-Couch-Full-Commit":"true"});
T(db2.save({_id:"1",a:2,b:4}).ok);
T(db2.open("1") != null);
restartServer();
T(db2.open("1") != null);
// You can update but without committing immediately, and then ensure
// everything is commited in the last step.
T(db.save({_id:"2",a:2,b:4}).ok);
T(db.open("2") != null);
T(db.ensureFullCommit().ok);
restartServer();
T(db.open("2") != null);
// However, it's possible even when flushed, that the server crashed between
// the update and the commit, and you don't want to check to make sure
// every doc you updated actually made it to disk. So record the instance
// start time of the database before the updates and then check it again
// after the flush (the instance start time is returned by the flush
// operation). if they are the same, we know everything was updated
// safely.
// First try it with a crash.
var instanceStartTime = db.info().instance_start_time;
T(db.save({_id:"3",a:2,b:4}).ok);
T(db.open("3") != null);
restartServer();
var commitResult = db.ensureFullCommit();
T(commitResult.ok && commitResult.instance_start_time != instanceStartTime);
// start times don't match, meaning the server lost our change
T(db.open("3") == null); // yup lost it
// retry with no server restart
var instanceStartTime = db.info().instance_start_time;
T(db.save({_id:"4",a:2,b:4}).ok);
T(db.open("4") != null);
var commitResult = db.ensureFullCommit();
T(commitResult.ok && commitResult.instance_start_time == instanceStartTime);
// Successful commit, start times match!
restartServer();
T(db.open("4") != null);
};
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