/**
 * This commands tests that moveChunk gives a proper response when the writeConcern cannot be met.
 * The test creates a sharded cluster with shards and config servers of different sizes to see how
 * moveChunk commands react as the writeConcern changes. It first sees that a writeConcern too high
 * for the config server replicaset succeeds because moveChunk passes w: majority to config servers.
 * It then passes a writeConcern too high for the to shard and sees that it fails. It then passes
 * a writeConcern too high for the from shard and sees that that fails. moveChunk does not yield
 * a writeConcernError. It should simply fail when the writeConcern is not met on the shards.
 */
load('jstests/libs/write_concern_util.js');

(function() {
"use strict";
var st = new ShardingTest({
    shards: {
        rs0: {nodes: 3, settings: {chainingAllowed: false}},
        rs1: {nodes: 5, settings: {chainingAllowed: false}}
    },
    mongos: 1,
    config: 1,
    configReplSetTestOptions: {settings: {chainingAllowed: false}}
});

var mongos = st.s;
var dbName = "move-chunk-wc-test";
var db = mongos.getDB(dbName);
var collName = 'leaves';
var coll = db[collName];
var numberDoc = 20;
var s0 = st.shard0.shardName;
var s1 = st.shard1.shardName;

coll.createIndex({x: 1}, {unique: true});
st.ensurePrimaryShard(db.toString(), s0);
st.shardColl(collName, {x: 1}, {x: numberDoc / 2}, {x: numberDoc / 2}, db.toString(), true);

for (var i = 0; i < numberDoc; i++) {
    coll.insert({x: i});
}
assert.eq(coll.count(), numberDoc);

// Checks that each shard has the expected number of chunks.
function checkChunkCount(s0Count, s1Count) {
    var chunkCounts = st.chunkCounts(collName, db.toString());
    assert.eq(chunkCounts[s0], s0Count);
    assert.eq(chunkCounts[s1], s1Count);
}
checkChunkCount(1, 1);

var req = {
    moveChunk: coll.toString(),
    find: {x: numberDoc / 2},
    to: s0,
    _secondaryThrottle: true,
    _waitForDelete: true
};

req.writeConcern = {
    w: 1,
    wtimeout: 30000
};
jsTest.log("Testing " + tojson(req));
var res = db.adminCommand(req);
assert.commandWorked(res);
assert(!res.writeConcernError, 'moveChunk had writeConcernError: ' + tojson(res));
checkChunkCount(2, 0);

// This should pass because w: majority is always passed to config servers.
req.writeConcern = {
    w: 2,
    wtimeout: 30000
};
jsTest.log("Testing " + tojson(req));
req.to = s1;
res = db.adminCommand(req);
assert.commandWorked(res);
assert(!res.writeConcernError, 'moveChunk had writeConcernError: ' + tojson(res));
checkChunkCount(1, 1);

// This should fail because the writeConcern cannot be satisfied on the to shard.
req.writeConcern = {
    w: 4,
    wtimeout: 3000
};
jsTest.log("Testing " + tojson(req));
req.to = s0;
res = db.adminCommand(req);
assert.commandFailed(res);
assert(!res.writeConcernError, 'moveChunk had writeConcernError: ' + tojson(res));
checkChunkCount(1, 1);

// This should fail because the writeConcern cannot be satisfied on the from shard.
req.writeConcern = {
    w: 6,
    wtimeout: 3000
};
jsTest.log("Testing " + tojson(req));
req.to = s0;
res = db.adminCommand(req);
assert.commandFailed(res);
assert(!res.writeConcernError, 'moveChunk had writeConcernError: ' + tojson(res));
checkChunkCount(1, 1);

// This should fail because the writeConcern is invalid and cannot be satisfied anywhere.
req.writeConcern = {
    w: "invalid",
    wtimeout: 3000
};
jsTest.log("Testing " + tojson(req));
req.to = s0;
res = db.adminCommand(req);
assert.commandFailed(res);
assert(!res.writeConcernError, 'moveChunk had writeConcernError: ' + tojson(res));
checkChunkCount(1, 1);
st.stop();
})();