[Flutter-Android] [R8-Proguard] Minify issue, missing classes when build app.

[hoyiliang]

Good day, we will refer to the following error log.

ERROR: Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in .../build/app/outputs/mapping/qaRelease/missing_rules.txt.
ERROR: R8: Missing class aQute.bnd.annotation.spi.ServiceProvider (referenced from: com.ctc.wstx.dtd.DTDSchemaFactory and 5 other contexts)
Missing class com.sun.activation.registries.LogSupport (referenced from: void javax.activation.MailcapCommandMap.<init>()  @and 4 other contexts)
Missing class com.sun.activation.registries.MailcapFile (referenced from: com.sun.activation.registries.MailcapFile[] javax.activation.MailcapCommandMap.DB and 5 other contexts)
Missing class java.awt.datatransfer.DataFlavor (referenced from: java.awt.datatransfer.DataFlavor[] javax.activation.DataHandler.emptyFlavors and 4 other contexts)
Missing class java.awt.datatransfer.Transferable (referenced from: javax.activation.DataHandler)
Missing class java.beans.BeanInfo (referenced from: void org.apache.log4j.config.PropertySetter.introspect())
Missing class java.beans.IntrospectionException (referenced from: void org.apache.log4j.config.PropertySetter.introspect())
Missing class java.beans.Introspector (referenced from: void org.apache.log4j.config.PropertySetter.introspect() and 2 other contexts)
Missing class java.beans.PropertyDescriptor (referenced from: java.beans.PropertyDescriptor[] org.apache.log4j.config.PropertySetter.props and 4 other contexts)

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:minifyQaReleaseWithR8'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.R8Task$R8Runnable
   > Compilation failed to complete

After some research around the web, I am expected to add some keep rules into proguard-rules.pro file to keep the classes that the SDK requires.

Some notes:

1. Only happens when building in Release mode because the build script only enables Minify in Release mode by default.
2. Using -dontwarn in the missing_rules.txt is not the solution. The app crashes when I try to call the SDK's methods.
3. I have tried to include the following keep rules, but the app still crashes when I call the SDK's methods.:

-keep class aQute.* { *; }
-keep class com.sun.* { *; }
-keep class java.awt.* { *; }
-keep class java.beans.* { *; }
-keep class com.skype.rt.** {*;}
-keep class com.azure.** {*;}
-keep class com.skype.android.** {*;}
-keep class com.microsoft.media.** {*;}
-keep class com.microsoft.dl.** {*;}

4. The libraries I am using, reference: https://learn.microsoft.com/en-us/azure/communication-services/quickstarts/chat/get-started?tabs=windows&pivots=programming-language-android

build.gradle
dependencies {
    implementation "com.azure.android:azure-communication-common:1.2.1"
    implementation "com.azure.android:azure-communication-chat:2.0.3"
    implementation "org.slf4j:slf4j-log4j12:1.7.29"
}

Please assist on this issue. Preferably I do not need to disable the Minify feature enabled by default.

Thanks!

[hoyiliang]

Update:

I found a working combination of entries in app level build.gradle and proguard-rules.pro. With these, I am able to build and call the SDK methods without error/crash.

However, I am unsure if the versions I chose for some libraries are appropriate (as in not too old/new).

If anyone has a better library version selections, or found out there are still some library missing, I greatly appreciate it if you could share.

The libraries that I am unsure of are:

implementation "biz.aQute.bnd:biz.aQute.bnd.annotation:6.1.0"

implementation group: 'org.apache.poi', name: 'poi-ooxml', version: '3.17'
implementation group: 'org.apache.xmlbeans', name: 'xmlbeans', version: '3.1.0'
implementation 'com.fasterxml:aalto-xml:1.2.2'
implementation 'com.fasterxml.jackson.core:jackson-databind:2.12.7.1'

implementation "org.slf4j:slf4j-api:1.7.36"
implementation "org.slf4j:slf4j-simple:1.7.36"

build.gradle
dependencies {
        // Azure Communication Service SDK
        implementation "com.azure.android:azure-core:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-logging:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-http:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-http-okhttp:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-http-httpurlconnection:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-jackson:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-rest:1.0.0-beta.14"
        implementation "com.azure.android:azure-core-credential:1.0.0-beta.14"

        implementation "com.azure.android:azure-communication-common:1.2.1"
        implementation "com.azure.android:azure-communication-chat:2.1.0"
        implementation "com.microsoft:trouter-client-android:0.1.1"
        implementation "biz.aQute.bnd:biz.aQute.bnd.annotation:6.1.0"

        implementation group: 'org.apache.poi', name: 'poi-ooxml', version: ‘4.1.2’
        implementation group: 'org.apache.xmlbeans', name: 'xmlbeans', version: '3.1.0'
        implementation 'com.fasterxml:aalto-xml:1.3.2’
        implementation 'com.fasterxml.jackson.core:jackson-databind:2.12.7.1'

        implementation "org.slf4j:slf4j-api:1.7.36"
        implementation "org.slf4j:slf4j-simple:1.7.36"
}

proguard-rules.pro
# ACS Chat & Dependencies
-dontwarn com.sun.activation.registries.LogSupport
-dontwarn com.sun.activation.registries.MailcapFile
-dontwarn java.awt.datatransfer.DataFlavor
-dontwarn java.awt.datatransfer.Transferable

-keep class javax.xml.stream.** { *; }
-keep class com.bea.xml.stream.** { *; }
-keep class com.azure.android.** { *; }
-keep class com.skype.** { *; }
-keep class com.microsoft.trouterclient.** { *; }
-keep class com.fasterxml.jackson.databind.ser.std.ClassSerializer { *; }
-keep class com.fasterxml.jackson.core.** { *; }