DeflateStream is not supported?

[inethui]

The following test fails with the error: System.NotSupportedException : This operation is not supported. This code works for Protobuf-net.

        [Fact]
        public void TestCompress()
        {
            using (DeflateStream dest = new DeflateStream(new MemoryStream(), CompressionMode.Compress))
            {
                Serializer.Serialize(dest, "Test");
            }
        }

[AqlaSolutions]

Stacktrace?

[inethui]

Stack Trace: 

DeflateStream.get_Position()
ProtoWriter.ctor(Stream dest, TypeModel model, SerializationContext context) line 886
TypeModel.Serialize(Stream dest, Object value, SerializationContext context) line 240
TypeModel.Serialize(Stream dest, Object value) line 227
Serializer.Serialize[T](Stream destination, T instance) line 135
UnitTest.TestCompress() line 170

[AqlaSolutions]

Yeah, it's expected that it's possible to get stream position, if it's not supported in DeflateStream than you can't use it directly. Though you can make a wrapper around DeflateStream which implements Position. It should just count written bytes.

[inethui]

But this code works for Protobuf-net. Is Aqla supposed to support whatever Protobuf-net provides? The following code works:

            using (DeflateStream dest = new DeflateStream(new MemoryStream(), CompressionMode.Compress))
            {
                ProtoBuf.Serializer.Serialize(dest, "Test");
            }

[AqlaSolutions]

Mostly it supports things from Protobuf-net, but not using Position property is a very implementation specific thing. Ok, I'll see if Position can be avoided. For now you can workaround it using a wrapper.

[inethui]

We've already had a serialization solution which is a mix of BinaryFormatter and ProtoBuf, each has its own issues. I'm trying to consolidate them into Aqla, but found these two issues. It would be very much appreciated if you can get them addressed.

[AqlaSolutions]

Can you provide an example with full cycle: serialization + deserialization using DeflateStream?

[inethui]

This is an example of how to serialize/deserialize into/from a DeflateStream:

        public void TestCompress()
        {
            byte[] bytes;
            using (MemoryStream stream = new MemoryStream())
            {
                using (DeflateStream dest = new DeflateStream(stream, CompressionMode.Compress))
                {
                    ProtoBuf.Serializer.Serialize(dest, "Test");
                }

                bytes = stream.ToArray();
            }

            using (var stream = new MemoryStream(bytes))
                using (DeflateStream dest = new DeflateStream(stream, CompressionMode.Decompress))
                {
                    var str = ProtoBuf.Serializer.Deserialize<string>(dest);
                    Assert.Equal("Test", str);
                }
        }

[AqlaSolutions]

Ok, I fixed it so that Position is not used unless it is really necessary. You can test it with the develop branch. But mind that some features require seeking during reading like If you try to reference an object from inside itself.

[inethui]

Thanks for the quick turn around. I want to make Aqla our standard serializer, but these two issues have caused many unit tests to fail. Now you have quickly fixed issue #36, it would be really helpful if you can also fix #35.

[inethui]

I got the following error while trying to run our tests with the Aqla develop branch: AqlaSerializer.ProtoAggregateException : One or multiple exceptions occurred: InvalidOperationException (Non-public member cannot be used with full dll compilation: Any idea what could be the cause?

[AqlaSolutions]

It means you are serializing a private field. If it's not the case can you give me a repro?

[inethui]

Yes, we are serializing private fields. We use reflection to find out all fields (public and private) and use RuntimeTypeModel APIs to register our classes and fields. This has never been a problem before.

[inethui]

I have encountered similar issues before. One thing I noticed is that if I download and use the binaries you built, then this problem goes away.

[inethui]

Can you please publish the binaries? I would like to give it a try.

[inethui]

What does "full dll compilation" mean?

[AqlaSolutions]

When you call RuntimeTypeModel.Compile(dllName) it generates dll that can serialize your classes without reflection. If works as any other compiled C# code so it can't access private members.

[AqlaSolutions]

It looks like you use DEBUG configuration of aqlaserializer project, that's why it attempts to test dll compilation. Just switch to release.

[inethui]

You are right, I was running in DEBUG configuration. However, I didn't call RuntimeTypeModel.Compile(dllName), instead what I called is RuntimeTypeModel.Default.CompileInPlace(). Does this have the same effect as "RuntimeTypeModel.Compile(dllName)"?

[inethui]

I'm having some trouble to build the release build of Aqla. Can you post the release build of it? Thanks

[inethui]

Never mind, I figured out how to create the release build. I've verified that this issue is fixed in develop branch. Now can you please create a nuget package? I will ask our IT to download it and put it in our internal nuget repo so that our system can start to use it.

[AqlaSolutions]

I've published the new release.