Okio in multiplatform iOS & Android

[yoman07]

Hi,
how to use Okio in kotlin multiplatform? I want to use openZip function, but I couldn't find in documentation how to properly get FileSystem. Most of examples use FileSystem.System but it won't work. I get "Unresolved reference: SYSTEM" I am able to get only FileSystem.SYSTEM_TEMPORARY_DIRECTORY.

[JakeWharton]

Zip support is currently only available for the JVM/Android. The SYSTEM filesystem is only available for JVM/Android and native as there is no appropriate filesystem for JS (browser).

Until #980 lands and is released you will have to actual/expect the SYSTEM filesystem yourself to access it from a common source set.

[pathconnected]

Is deflate & zip still unsupported on android / iOS?

[JakeWharton]

They have always been supported on Android. Native targets were added for deflate, gzip, and zip in 3.9.

[pathconnected]

Thank you. So the documentation in https://square.github.io/okio/multiplatform/ is outdated?

Compression (Deflater, Inflater, Gzip)

JVM-only.

[JakeWharton]

Yep

[JakeWharton]

Updated

[avenwu]

+1, Same error when trying to use the FileSystem.System API.

According to the okio changelog, the v3.1.0 support Hierarchical project structure.

Any help?

---

[avenwu]

Define a custom actual/expect can avoid the error. see #1115

[oldergod]

Any chance you could publish a demo repo?

[avenwu]

Any chance you could publish a demo repo?

Just create a demo project by AndroidStudio can reproduce the case, nothing else required. Are you trying to fix this reference error?

[darronschall]

Like this issue describes, I too am unable to use FileSystem.SYSTEM from inside the commonMain source set out of the box (using Okio 3.2.0). It is available in both androidMain and iosMain though. A simple expect/acutal wrapper does the trick:

// in commonMain platformFileSystem.kt
import okio.FileSystem

expect fun platformFileSystem(): FileSystem

// in androidMain platformFileSystem.kt
import okio.FileSystem

actual fun platformFileSystem(): FileSystem { return FileSystem.SYSTEM }

// in iosMain platformFileSystem.kt
import okio.FileSystem

actual fun platformFileSystem(): FileSystem { return FileSystem.SYSTEM }

Then, in commonMain code, use val fileSystem = platformFileSystem().