PublishTrimmed with Oracle.ManagedDataAccess.Core causes FileNotFoundException at runtime

Steps to repro.

1. mkdir Trimmed && cd Trimmed
2. dotnet new console
3. dotnet add package Oracle.ManagedDataAccess.Core --version 2.19.60
4. Replace Program.cs with the following code.

     using System;
     using Oracle.ManagedDataAccess.Client;
   
     namespace Trimmed
     {
         class Program
         {
             static void Main(string[] args)
             {
                 string connectionString = "connection string for Oracle DB";
   
                 using (OracleConnection con = new OracleConnection(connectionString))
                 {
                     using (OracleCommand cmd = con.CreateCommand())
                     {
                         try
                         {
                             con.Open();
                             cmd.BindByName = true;
                             cmd.CommandText = "select id from test_table where id = :id";
                             OracleParameter id = new OracleParameter("id", "test");
                             cmd.Parameters.Add(id);
   
                             OracleDataReader reader = cmd.ExecuteReader();
                             while (reader.Read())
                             {
                                 Console.WriteLine("id: " + reader.GetString(0));
                             }
   
                             Console.WriteLine();
                             Console.WriteLine("Press 'Enter' to continue");
   
                             reader.Dispose();
                         }
                         catch (Exception ex)
                         {
                             Console.WriteLine(ex);
                         }
                         Console.ReadLine();
                     }
                 }
             }
         }
     }
   
   

5. dotnet publish -c Release --runtime win-x64 /p:PublishTrimmed=true
6. .\bin\Release\netcoreapp3.1\win-x64\publish\Trimmed.exe

Error

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation.
 ---> System.TypeInitializationException: The type initializer for 'OracleInternal.ServiceObjects.OracleConnectionImpl' threw an exception.
 ---> System.TypeInitializationException: The type initializer for 'Oracle.ManagedDataAccess.Types.TimeStamp' threw an exception.
 ---> System.TypeInitializationException: The type initializer for 'System.Runtime.Serialization.Formatters.Binary.Converter' threw an exception.
 ---> System.IO.FileNotFoundException: Could not load file or assembly 'mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'. 指定されたファイルが見つかりません。
File name: 'mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
   at System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, RuntimeAssembly assemblyContext, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, AssemblyLoadContext assemblyLoadContext)
   at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, StackCrawlMark& stackMark, AssemblyLoadContext assemblyLoadContext)
   at System.Reflection.Assembly.Load(String assemblyString)
   at System.Runtime.Serialization.Formatters.Binary.Converter..cctor()


   --- End of inner exception stack trace ---
   at OracleInternal.Common.OracleTimeZone.GetInstance()
   at Oracle.ManagedDataAccess.Types.TimeStamp..cctor()
   --- End of inner exception stack trace ---
   at Oracle.ManagedDataAccess.Types.TimeStamp.InitializelatestTZversion()
   at OracleInternal.ServiceObjects.OracleConnectionImpl..cctor()
   --- End of inner exception stack trace ---
   at OracleInternal.ServiceObjects.OracleConnectionImpl..ctor()
   --- End of inner exception stack trace ---
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean wrapExceptions, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& hasNoDefaultCtor)
   at System.RuntimeType.CreateInstanceDefaultCtorSlow(Boolean publicOnly, Boolean wrapExceptions, Boolean fillCache)
   at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, Boolean wrapExceptions)
   at System.Activator.CreateInstance[T]()
   at OracleInternal.ConnectionPool.PoolManager`3.CreateNewPR(Int32 reqCount, Boolean bForPoolPopulation, ConnectionString csWithDiffOrNewPwd, OracleConnection connRefForCriteria, String instanceName, List`1 switchFailedInstNames)
   at OracleInternal.ConnectionPool.PoolManager`3.Get(ConnectionString csWithDiffOrNewPwd, Boolean bGetForApp, OracleConnection connRefForCriteria, String affinityInstanceName, Boolean bForceMatch)
   at OracleInternal.ConnectionPool.OraclePoolManager.Get(ConnectionString csWithNewPassword, Boolean bGetForApp, OracleConnection connRefForCriteria, String affinityInstanceName, Boolean bForceMatch)      
   at OracleInternal.ConnectionPool.OracleConnectionDispenser`3.Get(ConnectionString cs, PM conPM, ConnectionString pmCS, SecureString securedPassword, SecureString securedProxyPassword, OracleConnection connRefForCriteria)
   at Oracle.ManagedDataAccess.Client.OracleConnection.Open()
   at Trimmed.Program.Main(String[] args)

[jods4]

Good news everyone. After seeing Oracle tweet about 2.19.101 saying “BinaryFormatter issues are resolved”, I gave it a try.

It looks like you can now publish link-trimmed self-contained .net core applications without referencing mscorlib 4.0.0.0 and it works. 🎉

[jods4]

@alexkeh I am not aware of any recommandation from SQL team.

As far as my understanding of trimming goes, I’d say the same guidelines that apply to end-developer would apply to ISV.

1. There’s a list of things that don’t work in single-file publish, mostly revolving around accessing your assembly base path or file. There’s no “work-around” other than replacing the code with an alternative that doesn’t use these APIs. Since ODP.NET works for me, I conclude you don’t do that (and I don’t see why you would).

2. The “safe” assembly-trimming mode is based on referenced assemblies. As long as you don’t load an assembly dynamically there’s no issue. If you wanted to do that, I think you’d have to document a <TrimmerRootAssembly> that end-developers must add to their build. BinaryFormatter aside, works for me, so I don’t think you do that (and again I don’t see why you would).

3. The link-trimming mode is based on static code analysis, to find types and members that are actually used. End-developers will encounter issues if ODP.NET performs some non-statically typed code, e.g. by reflection, runtime emitted code, or using dynamic. This can be done but you’d need to use attributes as described in the blog post above to make the linker aware of the dynamically accessed members. Again, works for me, so the commonly used codepaths don’t seem to be concerned by that.

It looks to me like you’re very close to trimming-friendly. That pesky BinaryFormatter is the main roadblock, at least for my basic usage so far.