SERVER-31114 Perform targeted session invalidation on direct writes to `config.transactions`

1 files changed, 83 insertions, 0 deletions

diff --git a/jstests/replsets/retryable_writes_direct_write_to_config_transactions.js b/jstests/replsets/retryable_writes_direct_write_to_config_transactions.js
new file mode 100644
index 00000000000..62d0b840711
--- /dev/null
+++ b/jstests/replsets/retryable_writes_direct_write_to_config_transactions.js
@@ -0,0 +1,83 @@
+// Validates the expected behaviour of direct writes against the `config.transactions` collection
+(function() {
+    'use strict';
+
+    var replTest = new ReplSetTest({nodes: 2});
+    replTest.startSet();
+    replTest.initiate();
+
+    var priConn = replTest.getPrimary();
+    var db = priConn.getDB('TestDB');
+    var config = priConn.getDB('config');
+
+    assert.writeOK(db.user.insert({_id: 0}));
+    assert.writeOK(db.user.insert({_id: 1}));
+
+    const lsid1 = UUID();
+    const lsid2 = UUID();
+
+    const cmdObj1 = {
+        update: 'user',
+        updates: [{q: {_id: 0}, u: {$inc: {x: 1}}}],
+        lsid: {id: lsid1},
+        txnNumber: NumberLong(1)
+    };
+    assert.commandWorked(db.runCommand(cmdObj1));
+    assert.eq(1, db.user.find({_id: 0}).toArray()[0].x);
+
+    const cmdObj2 = {
+        update: 'user',
+        updates: [{q: {_id: 1}, u: {$inc: {x: 1}}}],
+        lsid: {id: lsid2},
+        txnNumber: NumberLong(1)
+    };
+    assert.commandWorked(db.runCommand(cmdObj2));
+    assert.eq(1, db.user.find({_id: 1}).toArray()[0].x);
+
+    assert.eq(1, config.transactions.find({'_id.id': lsid1}).itcount());
+    assert.eq(1, config.transactions.find({'_id.id': lsid2}).itcount());
+
+    // Invalidating lsid1 doesn't impact lsid2, but allows same statement to be executed again
+    assert.writeOK(config.transactions.remove({'_id.id': lsid1}));
+    assert.commandWorked(db.runCommand(cmdObj1));
+    assert.eq(2, db.user.find({_id: 0}).toArray()[0].x);
+    assert.commandWorked(db.runCommand(cmdObj2));
+    assert.eq(1, db.user.find({_id: 1}).toArray()[0].x);
+
+    // Ensure lsid1 is properly tracked after the recreate
+    assert.commandWorked(db.runCommand(cmdObj1));
+    assert.eq(2, db.user.find({_id: 0}).toArray()[0].x);
+
+    // Ensure garbage data cannot be written to the `config.transactions` collection
+    assert.writeError(config.transactions.insert({_id: 'String'}));
+    assert.writeError(config.transactions.insert({_id: {UnknownField: 'Garbage'}}));
+
+    // Ensure inserting an invalid session record manually without all the required fields causes
+    // the session to not work anymore for retryable writes for that session, but not for any other
+    const lsidManual = config.transactions.find({'_id.id': lsid1}).toArray()[0]._id;
+    assert.writeOK(config.transactions.remove({'_id.id': lsid1}));
+    assert.writeOK(config.transactions.insert({_id: lsidManual}));
+
+    const lsid3 = UUID();
+    assert.commandWorked(db.runCommand({
+        update: 'user',
+        updates: [{q: {_id: 2}, u: {$inc: {x: 1}}, upsert: true}],
+        lsid: {id: lsid3},
+        txnNumber: NumberLong(1)
+    }));
+    assert.eq(1, db.user.find({_id: 2}).toArray()[0].x);
+
+    // Ensure dropping the `config.transactions` collection breaks the retryable writes feature, but
+    // doesn't crash the server
+    assert(config.transactions.drop());
+    var res = assert.commandWorked(db.runCommand(cmdObj2));
+    assert.eq(0, res.nModified);
+    assert.eq(1, db.user.find({_id: 1}).toArray()[0].x);
+
+    assert(config.dropDatabase());
+    res = assert.commandWorked(db.runCommand(cmdObj2));
+    assert.eq(0, res.nModified);
+    assert.eq(1, db.user.find({_id: 1}).toArray()[0].x);
+
+    replTest.stopSet();
+})();