PHP
https://developers.google.cn/protocol-buffers/docs/proto3#json
JSON options
A proto3 JSON implementation may provide the following options:
Emit fields with default values: Fields with default values are omitted by default in proto3 JSON output. An implementation may provide an option to override this behavior and output fields with their default values.
how to set ?like:EmitDefaults or defaults_json
\Google\Protobuf\Internal\Message::existField
……
return $values !== $this->defaultValue($field);
Fields with default values are always omitted