// cursor1.js
// checks that cursors survive a chunk's move
(function() {

load("jstests/sharding/libs/find_chunks_util.js");

var s = new ShardingTest({name: "sharding_cursor1", shards: 2});

s.config.settings.find().forEach(printjson);

// create a sharded 'test.foo', for the moment with just one chunk
s.adminCommand({enablesharding: "test"});
s.ensurePrimaryShard('test', s.shard1.shardName);
s.adminCommand({shardcollection: "test.foo", key: {_id: 1}});

db = s.getDB("test");
let primary = s.getPrimaryShard("test").getDB("test");
let secondary = s.getOther(primary).getDB("test");

var numObjs = 30;
var bulk = db.foo.initializeUnorderedBulkOp();
for (let i = 0; i < numObjs; i++) {
    bulk.insert({_id: i});
}
assert.commandWorked(bulk.execute());
assert.eq(1,
          findChunksUtil.countChunksForNs(s.config, "test.foo"),
          "test requires collection to have one chunk initially");

// Cursor timeout only occurs outside of sessions. Otherwise we rely on the session timeout
// mechanism to kill cursors.
TestData.disableImplicitSessions = true;

// we'll split the collection in two and move the second chunk while three cursors are open
// cursor1 still has more data in the first chunk, the one that didn't move
// cursor2 buffered the last obj of the first chunk
// cursor3 buffered data that was moved on the second chunk
var cursor1 = db.foo.find().batchSize(3);
assert.eq(3, cursor1.objsLeftInBatch());
var cursor2 = db.foo.find().batchSize(5);
assert.eq(5, cursor2.objsLeftInBatch());
var cursor3 = db.foo.find().batchSize(7);
assert.eq(7, cursor3.objsLeftInBatch());

s.adminCommand({split: "test.foo", middle: {_id: 5}});
s.adminCommand({movechunk: "test.foo", find: {_id: 5}, to: secondary.getMongo().name});
assert.eq(2, findChunksUtil.countChunksForNs(s.config, "test.foo"));

// the cursors should not have been affected
assert.eq(numObjs, cursor1.itcount(), "c1");
assert.eq(numObjs, cursor2.itcount(), "c2");
assert.eq(numObjs, cursor3.itcount(), "c3");

// Test that a cursor with a 1 second timeout eventually times out.
var cur = db.foo.find().batchSize(2);
assert(cur.next(), "T1");
assert(cur.next(), "T2");
assert.commandWorked(s.admin.runCommand({
    setParameter: 1,
    cursorTimeoutMillis: 1000  // 1 second.
}));

assert.soon(function() {
    try {
        cur.next();
        cur.next();
        print("cursor still alive");
        return false;
    } catch (e) {
        return true;
    }
}, "cursor failed to time out", /*timeout*/ 30000, /*interval*/ 5000);

TestData.disableImplicitSessions = false;

s.stop();
})();