Retry not working

[andybdahl]

It seems the checkConnection() function in Retry never completes, the line Able.verbose { "checkConnection → End" } never runs.

If I use Able without the Retry layer, everything works as expected.

[twyatt]

Could you provide logs leading up to where the retry stalls?

[andybdahl]

Sure, here they are

2020-04-30 09:34:10.743 28277-28399/com.metricorr.app V/Retry: checkConnection → Begin
2020-04-30 09:34:10.744 28277-28399/com.metricorr.app V/Retry: checkConnection → consumeEach → newState = 2
2020-04-30 09:34:10.744 28277-28399/com.metricorr.app D/Retry: checkConnection → consumeEach → STATE_CONNECTED
2020-04-30 09:34:10.744 28277-28399/com.metricorr.app V/Retry: checkConnection → consumeEach → Repeat
2020-04-30 09:34:10.746 28277-28401/com.metricorr.app V/Retry: checkConnection → Begin
2020-04-30 09:34:10.747 28277-28401/com.metricorr.app V/Retry: checkConnection → consumeEach → newState = 2
2020-04-30 09:34:10.747 28277-28401/com.metricorr.app D/Retry: checkConnection → consumeEach → STATE_CONNECTED
2020-04-30 09:34:10.747 28277-28401/com.metricorr.app V/Retry: checkConnection → consumeEach → Repeat

[andybdahl]

What is happening is when I'm already connected, then a call to Retry.writeDescriptor for example causes a checkConnection() to never finish, as the device is already connected at the time of calling.

[twyatt]

It appears that subscription is not honoring the cancel request:

https://github.com/JuulLabs-OSS/able/blob/03b83fcd5cec77eb717144f49922e1bc3e596ed4/retry/src/main/java/Retry.kt#L98-L101

It's possible it's a bug in the Coroutines library, as the version of Able that you're using depends on an old (experimental) version of Coroutines.

https://github.com/JuulLabs-OSS/able/blob/03b83fcd5cec77eb717144f49922e1bc3e596ed4/build.gradle#L10

We're going to release Able 1.0.0 soon which removes the retry module and replaces it with keep-alive module that keeps the connection alive for you (reconnects on disconnect). It will allow users of Able to decide how to handle I/O retries.

I'll try to publish a 1.0.0-SNAPSHOT soon so you can experiment with it. In the mean time, you can look through the develop branch (and it's commits) to see how the API has changed.

[twyatt]

1.0.0-SNAPSHOT has been published, can you please try the new keep-alive module and let me know if that fits your use-case, or if you find any bugs. Thank you!

repositories {
    jcenter()
    maven { url "https://oss.sonatype.org/content/repositories/snapshots/" }
}

dependencies {
    implementation "com.juul.able:keep-alive:1.0.0-SNAPSHOT"
}

[twyatt]

This should be fixed in 0.8.0, please re-open if you still see the issue. Thanks for reporting.