SERVER-61184 Add limit to number of compound 2dsphere index keys we may generate

Co-authored-by: Henrik Edin<henrik.edin@mongodb.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/jstests/noPassthrough/compound_2dsphere_max_index_keys.js b/jstests/noPassthrough/compound_2dsphere_max_index_keys.js
new file mode 100644
index 00000000000..d6eaa272afa
--- /dev/null
+++ b/jstests/noPassthrough/compound_2dsphere_max_index_keys.js
@@ -0,0 +1,85 @@
+// Test that we can limit number of keys being generated by compounded 2dsphere indexes
+(function() {
+"use strict";
+
+// Launch mongod reduced max allowed keys per document.
+var runner = MongoRunner.runMongod({setParameter: "indexMaxNumGeneratedKeysPerDocument=200"});
+
+const dbName = jsTestName();
+const testDB = runner.getDB(dbName);
+var coll = testDB.t;
+
+const runTest = (indexDefinition) => {
+    coll.drop();
+
+    // Create compound 2dsphere index.
+    assert.commandWorked(coll.createIndex(indexDefinition));
+
+    // This polygon will generate 11 keys
+    let polygon = {
+        "type": "Polygon",
+        "coordinates": [[[0.0, 0.0], [1.0, 0.0], [0.0, 1.0], [0.0, 0.0]]]
+    };
+
+    // We can insert this just fine
+    assert.commandWorked(coll.insert({x: polygon, y: 1}));
+
+    // However, compounding with an array of 20 elements will exceed the number of keys (11*20 >
+    // 200) and should fail
+    assert.commandFailed(coll.insert(
+        {x: polygon, y: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]}));
+
+    // Now let's set a failpoint to relax the constraint so we can insert some bad documents.
+    assert.commandWorked(testDB.adminCommand(
+        {configureFailPoint: "relaxIndexMaxNumGeneratedKeysPerDocument", mode: "alwaysOn"}));
+
+    assert.commandWorked(coll.insert([
+        {
+            _id: 'problem1',
+            x: polygon,
+            y: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
+        },
+        {
+            _id: 'problem2',
+            x: polygon,
+            y: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
+        }
+    ]));
+
+    // And let's disable the failpoint again. At this point, the documents inserted above simulate
+    // old documents inserted prior to SERVER-61184.
+    assert.commandWorked(testDB.adminCommand(
+        {configureFailPoint: "relaxIndexMaxNumGeneratedKeysPerDocument", mode: "off"}));
+
+    // Confirm we cannot continue to insert bad documents.
+    assert.commandFailed(coll.insert(
+        {x: polygon, y: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]}));
+
+    // We should also get an error when we try to validate.
+    const validation = assert.commandWorked(coll.validate());
+    assert.eq(validation.errors.length, 1);
+    assert(validation.errors[0].includes('CannotBuildIndexKeys'));
+
+    // We should be able to remove a problem document.
+    assert.commandWorked(coll.deleteOne({_id: 'problem1'}));
+
+    // We should also be able to update a problem document to fix it.
+    assert.commandWorked(coll.updateOne({_id: 'problem2'}, {"$set": {y: []}}));
+
+    // But we shouldn't be able to update it to break it again.
+    try {
+        coll.updateOne(
+            {_id: 'problem2'},
+            {"$set": {y: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]}});
+        assert(false);
+    } catch (res) {
+        assert(res instanceof WriteError);
+    }
+};
+
+// Test both key orderings
+runTest({x: "2dsphere", y: 1});
+runTest({y: 1, x: "2dsphere"});
+
+MongoRunner.stopMongod(runner);
+})();