Unique constraints appearantly not checked when updating document

[xyrus02]

Given a NitriteCollection labeled list exists, for which there is a unique index for field "Data"
Given a document labeled 1 exists in the collection list with field "Data" = "test"
Given another document labeled 2 exists in the collection list with field "Data" = "test2"

[ { "_id": 1, "Data": "test"}, { "_id": 2, "Data": "test2"} ]

Reproduction steps: 2 would be updated so that "Data" changes to "test" knowing that the same value already exists on 1 and would violate the unique constraint. This would be achived by fetching 2 from the collection, setting "Data" to test and attempting to call update on the collection to store the changes.

Expectation: an exception is raised similar to a scenario where a third document with "Data" = "test" would be inserted.

Observation: no exception is raised. The change is stored and now the value "test" is not unique anymore within list - despite the unique constraint.

[xyrus02]

I suspect the error to be in DataService.java:186:

indexingService.refreshIndexEntry(oldDocument, document, nitriteId);

I think it should be:

indexingService.refreshIndexEntry(oldDocument, update, nitriteId);

[anidotnet]

I could not reproduce this issue. Here is a small test

@Test
public void testIssue151() {
    Document doc1 = new Document().put("id", "test-1").put("fruit", "Apple");
    Document doc2 = new Document().put("id", "test-2").put("fruit", "Ôrange");
    NitriteCollection coll = db.getCollection("test");
    coll.insert(doc1, doc2);

    coll.createIndex("fruit", indexOptions(IndexType.Unique));

    assertEquals(coll.find(eq("fruit", "Apple")).totalCount(), 1);

    Document doc3 = new Document(coll.find(eq("id", "test-2")).firstOrDefault());

    doc3.put("fruit", "Apple");
    coll.update(doc3);

    assertEquals(coll.find(eq("fruit", "Apple")).totalCount(), 2);
}

I am getting below valid exception

org.dizitart.no2.exceptions.UniqueConstraintException: NO2.10004: unique key constraint violation for fruit

	at org.dizitart.no2.internals.IndexingService.refreshIndexEntry(IndexingService.java:229)
	at org.dizitart.no2.internals.DataService.update(DataService.java:186)
	at org.dizitart.no2.internals.NitriteService.update(NitriteService.java:361)
	at org.dizitart.no2.internals.DefaultNitriteCollection.update(DefaultNitriteCollection.java:322)
	at org.dizitart.no2.internals.DefaultNitriteCollection.update(DefaultNitriteCollection.java:311)
	at org.dizitart.no2.internals.DefaultNitriteCollection.update(DefaultNitriteCollection.java:286)
	at org.dizitart.no2.internals.DefaultNitriteCollection.update(DefaultNitriteCollection.java:47)
	at org.dizitart.no2.CollectionFindByIndexTest.testIssue151(CollectionFindByIndexTest.java:389)

Probably you have missed this

Document doc3 = new Document(coll.find(eq("id", "test-2")).firstOrDefault());

Unless you copy it to a new document, any modification will be in-place. Even if you don't call update on collection, the document object will be updated.

On a second thought, I can make a small change, so that you will get a cloned document instead of the actual one and collection will be protected from this kind of mistakes.

[anidotnet]

Now this fix is available in 3.3.0-SNAPSHOT.

[xyrus02]

Thanks for picking this up and making the interface easier to use. I see your point with the necessity to clone the item before modifying it. I was indeed unter the impression that any "get" operation provides me with a clone, thus the whole point for an "update" operation.