Developing gRPC services and clients

gRPC provides an entire framework for RPCs based on HTTP and utilizing Google's protocol buffer format, a binary format that can convert into JSON but provides both a schema and, in many cases, a 10x performance improvement over JSON.

There are other formats in this space, such as Apache's Thrift, Cap'n Proto, and Google's FlatBuffers. However, these are not as popular and well supported, or satisfy a particular niche, while also being hard to use.

gRPC, like REST, is a client/server framework for making RPC calls. Where gRPC differs is that it prefers a binary message format called protocol buffers (proto for short).

This format has a schema stored in a .proto file that is used to generate the client, server, and messages in a native library for the language of your choice using a compiler. When a proto message is marshaled for transport on the wire, the binary representation will be the same for all languages.

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