Bug with querying overlaping string arrays

[adam8797]

Note: I'm working on a minimum working example of this bug, but I may not get to it. If you want to delay triage until then, thats understandable.

We've got a model class

public class MyDocument : CouchDocument
{
    // ...
    public List<string> Tags { get; set; }
    // ...
}

A query that I run elsewhere:

public async IAsyncEnumerable<MyDocument> Get(params string[] matchTags)
{
    var query = Coutext.MyDocuments.AsQueryable();

    // ...
    query = query.Where(x => x.Tags.Any(y => y.In(searchTags)));
    // ...

    await foreach (var model in query.ToAsyncEnumerable())
    {
        yield return model;
    }
}

If I print out mango queries before execution, I see this as the Mango Query for Get("Foo", "Bar"):

{{"selector":{"Tags":{"$elemMatch":{:{"$in":["Foo","Bar"]}}}}}}

This is invalid. I would expect the following query:

{"selector":{"Tags":{"$elemMatch":{"$in":["Foo","Bar"]}}}}

[adam8797]

@matteobortolazzo I've got that minimum solution for you:

using CouchDB.Driver;
using CouchDB.Driver.Extensions;
using CouchDB.Driver.Options;
using CouchDB.Driver.Query.Extensions;
using CouchDB.Driver.Types;

namespace CouchDbBugExampleApp
{
    internal class Program
    {
        static async Task Main(string[] args)
        {
            var context = new TestContext();

            await context.TestEntities.AddAsync(new TestEntity() { Name = "Test 1", Strings = { "foo", "bar" } });
            await context.TestEntities.AddAsync(new TestEntity() { Name = "Test 2", Strings = { "bar", "baz" } });
            await context.TestEntities.AddAsync(new TestEntity() { Name = "Test 3", Strings = { "baz", "foo" } });

            var stringsToSearch = new [] { "bar" };

            var query = context.TestEntities
                .AsQueryable()
                .Where(x => x.Strings.Any(y => y.In(stringsToSearch)));

            foreach (var e in await query.ToListAsync())
            {
                Console.WriteLine(e.Name);
            }
        }
    }

    public class TestContext : CouchContext
    {
        public CouchDatabase<TestEntity> TestEntities { get; set; }

        protected override void OnConfiguring(CouchOptionsBuilder optionsBuilder)
        {
            optionsBuilder
                .UseEndpoint("http://localhost:5984")
                .EnsureDatabaseExists()
                .UseBasicAuthentication("admin", "admin")
                .ConfigureFlurlClient(y =>
                {
                    y.BeforeCall = z => Console.WriteLine("\nSending Request To Couch: " + z + "\n" + z.RequestBody);
                });
        }
    }

    public class TestEntity : CouchDocument
    {
        public string Name { get; set; }

        public List<string> Strings { get; set; } = new();
    }
}

You will see that this produces an invalid mango query with CouchDB.Net 3.3.1

The query submitted to CouchDB is {"selector":{"strings":{"$elemMatch":{:{"$in":["bar"]}}}}}

[matteobortolazzo]

@adam8797 are you sure the query you expect is correct? I am trying to replicate but it doesn't seem to work with {"selector":{"Tags":{"$elemMatch":{"$in":["Foo","Bar"]}}}} either

[adam8797]

I'll double check against our database on Tuesday, but I thought I had that query working manually as a workaround.

[adam8797]

@mattobortolazzo Yes, it looks like the expected query is correct:

{
   "selector": {
      "Tags": {
         "$elemMatch": {
            "$in": [
               "Tag1",
               "Tag2"
            ]
         }
      }
   }
}

Returns the objects I expect using couchdb 3.2.2

[matteobortolazzo]

Pushed on dev

[adam8797]

Preliminary tests look good! I'll try and run something more rigorous tomorrow, but my functions which were broken just work correctly now.