mongo/jstests/sharding/query/find_getmore_cmd.js

/**
 * Test issuing raw find and getMore commands to mongos using db.runCommand().
 *
 * Always run on a fully upgraded cluster, so that {$meta: "sortKey"} projections use the newest
 * sort key format.
 * @tags: [
 *   requires_scripting,
 * ]
 */
import {ShardingTest} from "jstests/libs/shardingtest.js";

let cmdRes;
let cursorId;

let st = new ShardingTest({shards: 2});
st.stopBalancer();

// Set up a collection sharded by "_id" with one chunk on each of the two shards.
var db = st.s.getDB("test");
assert.commandWorked(db.adminCommand({enableSharding: db.getName(), primaryShard: st.shard0.shardName}));
let coll = db.getCollection("find_getmore_cmd");

assert.commandWorked(coll.insert({_id: -9, a: 4, b: "foo foo"}));
assert.commandWorked(coll.insert({_id: -5, a: 8}));
assert.commandWorked(coll.insert({_id: -1, a: 10, b: "foo"}));
assert.commandWorked(coll.insert({_id: 1, a: 5}));
assert.commandWorked(coll.insert({_id: 5, a: 20, b: "foo foo foo"}));
assert.commandWorked(coll.insert({_id: 9, a: 3}));

assert.commandWorked(coll.createIndex({b: "text"}));

db.adminCommand({shardCollection: coll.getFullName(), key: {_id: 1}});
assert.commandWorked(db.adminCommand({split: coll.getFullName(), middle: {_id: 0}}));
assert.commandWorked(db.adminCommand({moveChunk: coll.getFullName(), find: {_id: 1}, to: st.shard1.shardName}));

// Find with no options.
cmdRes = db.runCommand({find: coll.getName()});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 6);

// Find with batchSize greater than the number of docs residing on each shard. This means that a
// getMore is required between mongos and the shell, but no getMores are issued between mongos
// and mongod.
cmdRes = db.runCommand({find: coll.getName(), batchSize: 4});
assert.commandWorked(cmdRes);
assert.gt(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 4);
cmdRes = db.runCommand({getMore: cmdRes.cursor.id, collection: coll.getName()});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.nextBatch.length, 2);

// Find with batchSize less than the number of docs residing on each shard. This time getMores
// will be issued between mongos and mongod.
cmdRes = db.runCommand({find: coll.getName(), batchSize: 2});
assert.commandWorked(cmdRes);
assert.gt(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 2);
cursorId = cmdRes.cursor.id;
cmdRes = db.runCommand({getMore: cursorId, collection: coll.getName(), batchSize: 2});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, cursorId);
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.nextBatch.length, 2);
cmdRes = db.runCommand({getMore: cursorId, collection: coll.getName()});
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.nextBatch.length, 2);

// Combine skip, limit, and sort.
cmdRes = db.runCommand({find: coll.getName(), skip: 4, limit: 1, sort: {_id: -1}});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 1);
assert.eq(cmdRes.cursor.firstBatch[0], {_id: -5, a: 8});

// Find where adding limit and skip overflows.
const largeInt = new NumberLong("9223372036854775807");
cmdRes = db.runCommand({find: coll.getName(), skip: largeInt, limit: largeInt});
assert.commandFailed(cmdRes);
cmdRes = db.runCommand({find: coll.getName(), skip: largeInt, limit: largeInt, singleBatch: true});
assert.commandFailed(cmdRes);

// A predicate with $where.
cmdRes = db.runCommand({find: coll.getName(), filter: {$where: "this._id == 5"}});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 1);
assert.eq(cmdRes.cursor.firstBatch[0], {_id: 5, a: 20, b: "foo foo foo"});

// Tailable option should result in a failure because the collection is not capped.
cmdRes = db.runCommand({find: coll.getName(), tailable: true});
assert.commandFailed(cmdRes);

// $natural sort.
cmdRes = db.runCommand({find: coll.getName(), sort: {$natural: 1}});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 6);

// Should be able to sort despite projecting out the sort key.
cmdRes = db.runCommand({find: coll.getName(), sort: {a: 1}, projection: {_id: 1}});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 6);
assert.eq(cmdRes.cursor.firstBatch[0], {_id: 9});
assert.eq(cmdRes.cursor.firstBatch[1], {_id: -9});
assert.eq(cmdRes.cursor.firstBatch[2], {_id: 1});
assert.eq(cmdRes.cursor.firstBatch[3], {_id: -5});
assert.eq(cmdRes.cursor.firstBatch[4], {_id: -1});
assert.eq(cmdRes.cursor.firstBatch[5], {_id: 5});

// Ensure textScore meta-sort works in mongos.
cmdRes = db.runCommand({
    find: coll.getName(),
    filter: {$text: {$search: "foo"}},
    sort: {score: {$meta: "textScore"}},
    projection: {score: {$meta: "textScore"}},
});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 3);
assert.eq(cmdRes.cursor.firstBatch[0]["_id"], 5);
assert.eq(cmdRes.cursor.firstBatch[1]["_id"], -9);
assert.eq(cmdRes.cursor.firstBatch[2]["_id"], -1);

// User projection on $sortKey is illegal.
cmdRes = db.runCommand({find: coll.getName(), projection: {$sortKey: 1}, sort: {_id: 1}});
assert.commandFailed(cmdRes);
cmdRes = db.runCommand({find: coll.getName(), projection: {$sortKey: {$meta: "sortKey"}}, sort: {_id: 1}});
assert.commandFailed(cmdRes);

// User should be able to issue a sortKey meta-projection, as long as it's not on the reserved
// $sortKey field.
cmdRes = db.runCommand({
    find: coll.getName(),
    projection: {_id: 0, a: 0, b: 0, key: {$meta: "sortKey"}},
    sort: {_id: 1},
});
assert.commandWorked(cmdRes);
assert.eq(cmdRes.cursor.id, NumberLong(0));
assert.eq(cmdRes.cursor.ns, coll.getFullName());
assert.eq(cmdRes.cursor.firstBatch.length, 6);
assert.eq(cmdRes.cursor.firstBatch[0], {key: [-9]});
assert.eq(cmdRes.cursor.firstBatch[1], {key: [-5]});
assert.eq(cmdRes.cursor.firstBatch[2], {key: [-1]});
assert.eq(cmdRes.cursor.firstBatch[3], {key: [1]});
assert.eq(cmdRes.cursor.firstBatch[4], {key: [5]});
assert.eq(cmdRes.cursor.firstBatch[5], {key: [9]});

st.stop();