Cloud Firestore with gRPC build error

问题:

I’m working on an android application, which have to use gRPC and Firestore. However, when I added both one of module from ‘io.grpc’ group dependency (e.g. io.grpc:grpc-okhttp:1.7.0) and firestore dependency (com.google.firebase:firebase-firestore:11.4.2) in the build gradle config, I got a build error “Unable to merge dex”. After with ‘stacktrace’ build option, I saw that the problem is

Multiple dex files define Lio/grpc/internal/OobChannel$5;

It could happen if firestore uses grpc-core module, but there is no one similar in tree dependencies, which I got using [androidDependencies] gradle task. I tried to exclude io.grpc like this:

implementation ('com.google.firebase:firebase-firestore:11.4.2') {
    exclude group: 'io.grpc'
}

but there was the same error. Then I thought what if I exclude all ‘io.grpc.’ transitive dependencies from grpc module dependencies with adding grpc-core for internal classes. In this way, I wrote ugly dependencies just for test

implementation 'com.google.firebase:firebase-firestore:11.4.2'
implementation('io.grpc:grpc-okhttp:1.7.0') {
    exclude group: 'io.grpc'
}
implementation('io.grpc:grpc-protobuf-lite:1.7.0') {
    exclude group: 'io.grpc'
}
implementation('io.grpc:grpc-stub:1.7.0') {
    exclude group: 'io.grpc'
}
implementation 'io.grpc:grpc-core:1.7.0'

I was surprised when it successfully compiled, but after launch app, it crashed with java.lang.RuntimeException: Internal error in Firestore (0.6.6-dev)

Caused by: java.lang.NoSuchMethodError: No static method zzcyc()Lio/grpc/ManagedChannelProvider; in class Lio/grpc/ManagedChannelProvider; or its super classes (declaration of 'io.grpc.ManagedChannelProvider' appears in /data/app/com.zipr.test-2/split_lib_dependencies_apk.apk)

I use gradle 3.0.0-rc1 with enabling multidex support. I deleted .gradle, build directories, cleaned rebuilt project, but I still have build error. What can I do to resolve this problem?

回答1:

Due to a variety of factors that constrain the way we build Android SDKs at Google, Firestore proguards a copy of gRPC within itself. Unfortunately this is leaky and you're running into the fallout: the 11.4.2 Firestore SDK is incompatible with any external gRPC :-(.

This is essentially our top issue for the Firestore Android SDK and I'm sorry you've run into it.