pq is a tool which deserializes protobuf messages given a set of pre-compiled .fdset files. It can understand varint-delimited streams, and it can connect to Kafka.
pq will pretty-print when outputting to a tty, but you should pipe it to jq for more fully-featured json handling.
Due to serde-protobuf being (sadly) almost abandonware at this point, I copy-pasted the source files into pq's src. Using a git override was causing me to be unable to publish with Rust 1.19.0.
The files:
are not written by me. Original author is https://github.com/dflemstr.
pq is on crates.io: cargo install pq. You can also download a static binary from the releases page.
To set up, put your *.fdset files in ~/.pq (specify an alternate directory with the FDSET_PATH= env var):
$ protoc -o dog.fdset dog.proto
$ protoc -o person.fdset person.proto
$ cp *.fdset ~/.pq/
Pipe a single compiled protobuf message:
$ pq --msgtype com.example.dog.Dog <./tests/samples/dog
{
"age": 4,
"breed": "poodle",
"temperament": "excited"
}
Pipe a varint-delimited stream:
$ pq --msgtype com.example.dog.Dog --stream varint <./tests/samples/dog_stream
{
"age": 10,
"breed": "gsd",
"temperament": "aggressive"
}
Consume from a Kafka stream:
$ pq kafka my_topic --brokers 192.168.0.1:9092 --beginning --count 1 --msgtype com.example.dog.Dog
{
"age": 10,
"breed": "gsd",
"temperament": "aggressive"
}
Convert a Kafka stream to varint-delimited:
``` $ pq kafka my_topic --brokers=192.168.0.1:9092 --count 1 --convert varint |\
pq --msgtype com.example.dog.Dog --stream varint { "age": 10, "breed": "gsd", "temperament": "aggressive" } ```