SERVER-43762 Move top_drop.js from noPassthroughWithMongod to Core

1 files changed, 85 insertions, 0 deletions

diff --git a/jstests/core/top_drop.js b/jstests/core/top_drop.js
new file mode 100644
index 00000000000..56abb9a634d
--- /dev/null
+++ b/jstests/core/top_drop.js
@@ -0,0 +1,85 @@
+/**
+ * Checks that top removes entries after dropping a collection or database.
+ *
+ * @tags: [
+ *   assumes_against_mongod_not_mongos,
+ *   requires_non_retryable_writes,
+ * ]
+ */
+(function() {
+"use strict";
+
+let topDB = db.getSiblingDB("topdrop");
+assert.commandWorked(topDB.dropDatabase());
+
+// Asserts that the output of top contains exactly these collection entries for topDB.
+function checkTopEntries(expectedEntries) {
+    let res = topDB.adminCommand("top");
+    if (!res.ok) {
+        assert.commandFailedWithCode(res, [ErrorCodes.BSONObjectTooLarge, 13548]);
+        return;
+    }
+
+    let entriesInTop = Object.keys(res.totals).filter(function(ns) {
+        // This filter only includes non-system collections in our test database.
+        const tenantId = topDB.getName() + ".";
+        const systemCollectionPrefix = "system.";
+        return ns.startsWith(tenantId) && !ns.startsWith(tenantId + systemCollectionPrefix);
+    });
+    let expectedEntryNames = expectedEntries.map(function(coll) {
+        return coll.getFullName();
+    });
+
+    const entriesAreEqual = friendlyEqual(entriesInTop.sort(), expectedEntryNames.sort());
+    if (!entriesAreEqual) {
+        // TODO(SERVER-26750): This block can be removed once SERVER-26750 is resolved.
+        jsTest.log("Warning: expected to see " + tojson(expectedEntryNames) + " in top, but got " +
+                   tojson(entriesInTop));
+
+        assert.lt(expectedEntryNames.length,
+                  entriesInTop.length,
+                  "Fewer entries in top than expected; got " + tojson(entriesInTop) +
+                      " but expected " + tojson(expectedEntryNames) + "\nFull top output:\n" +
+                      tojson(res.totals));
+
+        // We allow an unexpected entry in top if the insert counter has been cleared. This is
+        // probably due to a background job releasing an AutoGetCollectionForReadCommand for
+        // that collection.
+        entriesInTop.forEach(function(coll) {
+            if (expectedEntryNames.includes(coll)) {
+                return;
+            }
+
+            let topStats = res.totals[coll];
+            assert.eq(0,
+                      res.totals[coll].insert.count,
+                      coll + " has unexpected insert entries in top. Full top output:\n" +
+                          tojson(res.totals));
+        });
+    }
+}
+
+// Create a few entries in top.
+assert.commandWorked(topDB.coll1.insert({}));
+assert.commandWorked(topDB.coll2.insert({}));
+assert.commandWorked(topDB.coll3.insert({}));
+checkTopEntries([topDB.coll1, topDB.coll2, topDB.coll3]);
+
+// Check that dropping a collection removes that collection but leaves the others.
+assert.commandWorked(topDB.runCommand({drop: "coll3"}));
+checkTopEntries([topDB.coll1, topDB.coll2]);
+
+// Check that dropping the database removes the remaining collections.
+assert.commandWorked(topDB.dropDatabase());
+checkTopEntries([]);
+
+// Check that top doesn't keep state about non-existent collections.
+assert.commandWorked(topDB.dropDatabase());
+topDB.foo.find().itcount();
+topDB.baz.update({}, {$set: {a: 1}});
+topDB.bar.remove({});
+
+checkTopEntries([]);
+
+assert.commandWorked(topDB.dropDatabase());
+}());