mongodb/jstests/noPassthrough/indexbg2.js

// Test background index creation w/ constraints

load( "jstests/libs/slow_weekly_util.js" );

var testServer = new SlowWeeklyMongod( "indexbg2" );
var db = testServer.getDB( "test" );
var baseName = "jstests_index12";

var parallel = function() {
    return db[ baseName + "_parallelStatus" ];
};

var resetParallel = function() {
    parallel().drop();
};

var doParallel = function( work ) {
    resetParallel();
    startMongoProgramNoConnect( "mongo", "--eval", work + "; db." + baseName + "_parallelStatus.save( {done:1} );", db.getMongo().host );
};

var doneParallel = function() {
    return !!parallel().findOne();
};

var waitParallel = function() {
    assert.soon( function() { return doneParallel(); }, "parallel did not finish in time", 300000, 1000 );
};

var doTest = function() {
    "use strict";
    var size = 10000;
    while (1) { // if indexing finishes before we can run checks, try indexing w/ more data
        print("size: " + size);
        var fullName = "db." + baseName;
        var t = db[baseName];
        t.drop();

        db.eval(function(size) {
            for (var i = 0; i < size; ++i) {
                db.jstests_index12.save({ i: i });
            }
        },
            size);
        assert.eq(size, t.count());

        doParallel(fullName + ".ensureIndex( {i:1}, {background:true, unique:true} )");
        try {
            // wait for indexing to start
            assert.soon(function() { return 2 == db.system.indexes.count({ ns: "test." + baseName }); }, "no index created", 30000, 50);
            t.save({ i: 0, n: true });
            t.save({ i: size - 1, n: true });
        } catch (e) {
            // only a failure if we're still indexing
            // wait for parallel status to update to reflect indexing status
            sleep(1000);
            if (!doneParallel()) {
                throw e;
            }
        }
        if (!doneParallel()) {
            break;
        }
        print("indexing finished too soon, retrying...");
        size *= 2;
        assert(size < 5000000, "unable to run checks in parallel with index creation");
    }

    waitParallel();

    /* it could be that there is more than size now but the index failed
     to build - which is valid.  we check index isn't there. 
     */
    if (t.count() != size) {
        assert.eq(1, t.getIndexes().length, "change in # of elems yet index is there");
    }

};

doTest();

testServer.stop();