Hello,
I'm sorry for misunderstanding.
Upon investigation, I got a similar error (though not exactly the same), which I can resolve by turning on the "C implementation" of Protobuf extension.
In particular, the PHP client library depends on the gRPC and protobuf, as written in
README .
If you follow the "Protobuf Runtime library" section of
this page , you will probably install this C implementation of Protobuf already.
Could you use "
php -i | grep protobuf" to check if you have this installed?
If not yet, could you try installing it and try again?