Support I/O stream

[chenfei0928]

If I deserialize a json from file system, deserialize method require me full read the file to a string.
Can it support read and write json content from I/O stream, like Gson done?

[sandwwraith]

We are planning a migration to kotlin multiplatform IO library – https://github.com/Kotlin/kotlinx-io . JSON parser would support both strings and kotlinx.io inputs.

[gajicm93]

This is quite a bummer because I know for a fact that Android can crash when a very large JSON payload is converted to a String at once.

When can we expect a streaming parse? Thanks.

[jcraane]

We indeed face this issue when per persist large json (the apps data) which sometimes triggers OutOfMemory.

[sdeleuze]

We are interested by that one for Spring Framework support, beware that for Spring MVC we typically deal with InputStream / OutputStream while on Spring WebFlux side we typically deal with java.nio.ByteBuffer, potentially in combination with the upcoming JSON streaming support (#1073).

[epicstar]

This is quite a bummer because I know for a fact that Android can crash when a very large JSON payload is converted to a String at once.

Yes, this should be considered a stopper for all Android applications.

[mobiletoly]

Any news or roadmap?

[sandwwraith]

It's planned for 1.1 or 1.2

[ln-12]

Seems like the feature didn't make into 1.1.0-RC. Currently, it's the only reason why I would not feel confident shipping it in a production app.

[MolotovCherry]

Really sad, I was looking forward to this being supported

[sdeleuze]

Could you please add support for that in 1.2 in order to allow Spring to use it in Spring Boot 2.5 ?

[slavonnet]

+100500 votes! How read big json without buffer, flow or streams?

[chris-hatton]

I'm developing an application with kotlinx.serialization and came to a point where I really want to implement a Flow<T> of objects from Server to Client, based on the HTTP return stream. It seems unfeasible to do this at the moment due to lack of stream processing support with kotlinx.serialization. This is the biggest weakness I can see with this otherwise great library...

Others have mentioned resource usage; but I wanted to bring another use-case reason to support streaming. Thanks for considering.

[chris-hatton]

If kotlinx.io has been put on hold; could maintaining developers of kotlinx.serialization consider a separate effort to expose a streaming API? I have seen suggestions that parsing is modelled around a stream internally, but for some reason this isn't exposed.

[sandwwraith]

I have seen suggestions that parsing is modelled around a stream internally

that (wasn't) true

We currently have progress on working implementation over Java's InputStream/OutputStream (#1569 ) You can take a look and tell if that fits your needs.

[qwwdfsad]

Fixed in 1.3.0-RC

[slavonnet]

random EOF exceptions on heavy loads.

[sandwwraith]

@slavonnet Can you please create a separate issue with a reproducer or at least a description of conditions under which exception occurs?

[martinbonnin]

Is there a separate issue for multiplatform streaming ?

[sandwwraith]

@martinbonnin I've cerated one for you: #1714