Bug/Regression doing a query with a jsonb column as string with 2.1.* about dapper

[mgravell]

nit: await using var conn = new NpgsqlConnection(_connectionString);, but: great repro, thanks - looking

[mgravell]

great; that's a workaround, and we'll get the code fixed for next release

[mgravell]

This change will almost certainly be reverted; it broke other scenarios, where string is handled more flexibly. I'll check more options.

[roji]

@lucax88x the ADO tests in that gist pass, only dapper_should_work_with_json_net seems to fail.

[mgravell]

I imagine that what's happening here is that npgsql is doing the deserialize, and giving us something that isn't a string (but rather: a rich object) - and we're expecting it to be a string. This is probably related to Dapper (vanilla) using the untyped data read API in some cases. Dapper.AOT does a better job of preferring typed data, so I imagine that Dapper.AOT would explicitly request a string, and receive a string. Any chance you can try the same query with Dapper AOT enabled? Or provide a full repro?

[lucax88x]

There's a github link with a full repro on top.

Clone the repo, and run the tests, it will fire up a db with test containers and run the query.

I can try with AOT tomorrow!

[mgravell]

See https://aot.dapperlib.dev/gettingstarted

[mgravell]

apologies, I overlooked the repro; taking a peek

[mgravell]

I'm a little confused... it... works? (I haven't changed anything except the connection string)

and at the command-line:

   09:39:49  DapperBug.Tests  main   8.0.200   13.796s   
➜ dotnet test
  Determining projects to restore...
  All projects are up-to-date for restore.
  DapperBug -> C:\Code\dapper-bug\DapperBug\bin\Debug\net8.0\DapperBug.dll
  DapperBug.Tests -> C:\Code\dapper-bug\DapperBug.Tests\bin\Debug\net8.0\DapperBug.Tests.dll
Test run for C:\Code\dapper-bug\DapperBug.Tests\bin\Debug\net8.0\DapperBug.Tests.dll (.NETCoreApp,Version=v8.0)
Microsoft (R) Test Execution Command Line Tool Version 17.9.0 (x64)
Copyright (c) Microsoft Corporation.  All rights reserved.

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.

Passed!  - Failed:     0, Passed:     1, Skipped:     0, Total:     1, Duration: < 1 ms - DapperBug.Tests.dll (net8.0)

What should I be seeing?

[mgravell]

it is possible that this can be fixed with a one-liner in SqlMapper.cs L217:

-                [typeof(string)] = DbType.String,
+                [typeof(string)] = new(DbType.String, TypeMapEntryFlags.SetType | TypeMapEntryFlags.UseGetFieldValue),

can check as soon as we can repro

on a per-consumer-project basis, we can check this with

SqlMapper.AddTypeMap(typeof(string), DbType.String, true);

[lucax88x]

I'm a little confused... it... works? (I haven't changed anything except the connection string)

and at the command-line:

   09:39:49  DapperBug.Tests  main   8.0.200   13.796s   
➜ dotnet test
  Determining projects to restore...
  All projects are up-to-date for restore.
  DapperBug -> C:\Code\dapper-bug\DapperBug\bin\Debug\net8.0\DapperBug.dll
  DapperBug.Tests -> C:\Code\dapper-bug\DapperBug.Tests\bin\Debug\net8.0\DapperBug.Tests.dll
Test run for C:\Code\dapper-bug\DapperBug.Tests\bin\Debug\net8.0\DapperBug.Tests.dll (.NETCoreApp,Version=v8.0)
Microsoft (R) Test Execution Command Line Tool Version 17.9.0 (x64)
Copyright (c) Microsoft Corporation.  All rights reserved.

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.

Passed!  - Failed:     0, Passed:     1, Skipped:     0, Total:     1, Duration: < 1 ms - DapperBug.Tests.dll (net8.0)

What should I be seeing?

I'm a little confused... it... works? (I haven't changed anything except the connection string)

and at the command-line:

   09:39:49  DapperBug.Tests  main   8.0.200   13.796s   
➜ dotnet test
  Determining projects to restore...
  All projects are up-to-date for restore.
  DapperBug -> C:\Code\dapper-bug\DapperBug\bin\Debug\net8.0\DapperBug.dll
  DapperBug.Tests -> C:\Code\dapper-bug\DapperBug.Tests\bin\Debug\net8.0\DapperBug.Tests.dll
Test run for C:\Code\dapper-bug\DapperBug.Tests\bin\Debug\net8.0\DapperBug.Tests.dll (.NETCoreApp,Version=v8.0)
Microsoft (R) Test Execution Command Line Tool Version 17.9.0 (x64)
Copyright (c) Microsoft Corporation.  All rights reserved.

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.

Passed!  - Failed:     0, Passed:     1, Skipped:     0, Total:     1, Duration: < 1 ms - DapperBug.Tests.dll (net8.0)

What should I be seeing?

Wow.

This is extremely weird, I lost two hours for that.

So, stay with me:
update the git repo
run the compose from the root
docker compose -f docker-compose.yml up

now, you have 2 tests from the solution
-CreateTables
-RunAloneNotTogetherWithCreateTables

1. Try to run CreateTables ALONE so you have the structure.
2. Now run the RunAloneNotTogetherWithCreateTable ALONE and it should give the Exception above (now reproduced)

But, if for some reason, you try to run both of them together, CreateTables will fail because table is already there (which is OK), but the RunAloneNotTogetherWithCreateTables will be green (WTF?)!

Something must happening with assembly...

Gonna try with your map.

[lucax88x]

SqlMapper.AddTypeMap(typeof(string), DbType.String, true);

I can confirm it works.

[mgravell]

Npgsql.PostgresException : 3D000: database "test" does not exist

so... I don't think it is connecting to the containerized database, but... I think we understand the problem well enough now

[lucax88x]

Create the db in the container :)

[lucax88x]

thanks for the quick answer btw.

[mgravell]

a couple of subtle behaviour changes with exception messages, but : within tolerance (and in some cases, clearer)

[lucax88x]

@mgravell

I don't know where the problem is, but I'm noticing the same bug using npgsql 8 and dapper 2.0.151.

I did another repro using a online postgresql.

https://gist.github.com/lucax88x/69c6deb14b80c856271534de5c10e1ad

dapper + json.net
dapper without json.net

npgsql with json.net
ngpsql without json.net

Without the workaround (the SqlMapper one) the one with dapper and json.net fails.

So I think the regression didn't come with 2.1 but rather from 8.0 of npgsql.

[mgravell]

It looks like we still haven't shipped NuGet packages for this - will fix However: IIRC npgsql now marks this global API as deprecated, preferring a column-specific configuration, so I'm sure they'd say "we already fixed this: the fix is to stop using that API" (apologies if I'm misrepresenting this - I don't do much npgsql)

…

On Thu, 14 Mar 2024, 12:51 Luca Trazzi, ***@***.***> wrote: @mgravell <https://github.com/mgravell> I don't know where the problem is, but I'm noticing the same bug using npgsql 8 and dapper 2.0.151. I did another repro using a online postgresql. https://gist.github.com/lucax88x/69c6deb14b80c856271534de5c10e1ad dapper + json.net dapper without json.net npgsql with json.net ngpsql without json.net Without the workaround (the SqlMapper one) the one with dapper and json.net fails. So I think the regression didn't come with 2.1 but rather from 8.0 of npgsql. — Reply to this email directly, view it on GitHub <#2049 (comment)> or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAEHMAFKXOWA7YXJ27DRADYYGMMJBFKMF2HI4TJMJ2XIZLTSOBKK5TBNR2WLJDUOJ2WLJDOMFWWLO3UNBZGKYLEL5YGC4TUNFRWS4DBNZ2F6YLDORUXM2LUPGBKK5TBNR2WLJDUOJ2WLJDOMFWWLLTXMF2GG2C7MFRXI2LWNF2HTAVFOZQWY5LFUVUXG43VMWSG4YLNMWVXI2DSMVQWIX3UPFYGLLDTOVRGUZLDORPXI6LQMWWES43TOVSUG33NNVSW45FGORXXA2LDOOJIFJDUPFYGLKTSMVYG643JORXXE6NFOZQWY5LFU4YTMMJTGM2DLAVEOR4XAZNFNFZXG5LFUV3GC3DVMWVDEMJXGAYDEMJRGUZ2O5DSNFTWOZLSUZRXEZLBORSQ> . You are receiving this email because you were mentioned. Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub> .

[mgravell]

https://github.com/DapperLib/Dapper/releases/tag/2.1.37

[lucax88x]

It looks like we still haven't shipped NuGet packages for this - will fix However: IIRC npgsql now marks this global API as deprecated, preferring a column-specific configuration, so I'm sure they'd say "we already fixed this: the fix is to stop using that API" (apologies if I'm misrepresenting this - I don't do much npgsql)
…
On Thu, 14 Mar 2024, 12:51 Luca Trazzi, @.***> wrote: @mgravell https://github.com/mgravell I don't know where the problem is, but I'm noticing the same bug using npgsql 8 and dapper 2.0.151. I did another repro using a online postgresql. https://gist.github.com/lucax88x/69c6deb14b80c856271534de5c10e1ad dapper + json.net dapper without json.net npgsql with json.net ngpsql without json.net Without the workaround (the SqlMapper one) the one with dapper and json.net fails. So I think the regression didn't come with 2.1 but rather from 8.0 of npgsql. — Reply to this email directly, view it on GitHub <#2049 (comment)> or unsubscribe https://github.com/notifications/unsubscribe-auth/AAAEHMAFKXOWA7YXJ27DRADYYGMMJBFKMF2HI4TJMJ2XIZLTSOBKK5TBNR2WLJDUOJ2WLJDOMFWWLO3UNBZGKYLEL5YGC4TUNFRWS4DBNZ2F6YLDORUXM2LUPGBKK5TBNR2WLJDUOJ2WLJDOMFWWLLTXMF2GG2C7MFRXI2LWNF2HTAVFOZQWY5LFUVUXG43VMWSG4YLNMWVXI2DSMVQWIX3UPFYGLLDTOVRGUZLDORPXI6LQMWWES43TOVSUG33NNVSW45FGORXXA2LDOOJIFJDUPFYGLKTSMVYG643JORXXE6NFOZQWY5LFU4YTMMJTGM2DLAVEOR4XAZNFNFZXG5LFUV3GC3DVMWVDEMJXGAYDEMJRGUZ2O5DSNFTWOZLSUZRXEZLBORSQ . You are receiving this email because you were mentioned. Triage notifications on the go with GitHub Mobile for iOS https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675 or Android https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub .

if you check the second repro I'm not using the global one, so they didn't fix, also because the problem is occuring only with dapper

[mgravell]

@roji can I summon your wisdom here? Problem is JSON deserialize kicking in when using the untyped read API, but actually wanting a string; there are long reasons (fixed in AOT) why typed read is a PITA. Anything more I can do the detect this problem before it happens?

[roji]

Hey @mgravell... Is this the repro (from the OP)? That's odd - by default, Npgsql should absolutely return a string for an untyped read of a PG jsonb.

If I I tried to repro this without Dapper (similar to the gist in #2049 (comment)) and couldn't (see below) - is it possible to get an ADO.NET-only code sample that shows what Dapper is doing when stuff fails?

Re NpgsqlConnection.GlobalTypeMapper being obsolete, that shouldn't have anything to do with this; we now recommend using the newer DbDataSource API to create connections, and to configure plugins such as Json.NET there, so:

var builder = new NpgsqlDataSourceBuilder("Host=localhost;Username=test;Password=test");
builder.UseJsonNet();
await using var dataSource = builder.Build();

await using var conn = await dataSource.OpenConnectionAsync();

Attempted ADO-only repro

#pragma warning disable CS0618 // Type or member is obsolete
NpgsqlConnection.GlobalTypeMapper.UseJsonNet();
#pragma warning restore CS0618 // Type or member is obsolete

await using var conn = new NpgsqlConnection("Host=localhost;Username=test;Password=test");
await conn.OpenAsync();

Console.WriteLine("Creating and seeding data");

await conn.ExecuteAsync("""
                        drop table if exists posts;
                        create table public.posts
                        (
                            postid  integer generated by default as identity
                        constraint "PK_posts"
                        primary key,
                            title   text  not null,
                        content jsonb not null
                            );

                        insert into public.posts (postid, title, content) values (1, 'title', '{"Prop1": "2", "Prop2": 2}');
                        """);

await using (var command = new NpgsqlCommand("select content from public.posts", conn))
await using (var reader = await command.ExecuteReaderAsync())
{
    while (await reader.ReadAsync())
    {
        Console.WriteLine($"Content typed: {reader.GetFieldValue<string>(0)}");
        Console.WriteLine($"Content untyped: {reader.GetValue(0)}");
    }
}

// The following indeed throws:
_ = await conn.QueryFirstOrDefaultAsync<string>("select content from public.posts");

[lucax88x]

@roji this is a simpler repro using both ado and dapper.

https://gist.github.com/lucax88x/69c6deb14b80c856271534de5c10e1ad

[mgravell]

crossref #2070

[mgravell]

https://github.com/DapperLib/Dapper/releases/tag/2.1.42