/nats-replay

Primary LanguageRust

nats-replay

This little utility allows you to easily record and replay UDP data streams, leveraging the NATS message queue

Usage

  1. Have a running NATS Jetstream server running

  2. Create your config file

  3. Build the program with cargo build --release

  4. Run the program with CONFIG_PATH=<config_path> ./target/release/nats-replay

Configuration

The configuration file is a JSON file

Mandatory arguments

  • nats_address: URL of the NATS broker (example: nats://localhost)
  • stream_name: Stream name on the NATS broker
  • mode: Which mode to run the program: info, record, or replay

Record mode

In this mode the system will receive and save packets to the stream.

  • bind_address: Bind address of the UDP socket
  • buffer_size: Size of the UDP socket buffer (default: 16384 bytes)
  • nats_buffer_size: Size of the NATS send buffer (default: 16384 messages)
  • flush_stream: Whenever the stream has to be reset on startup
  • skip_stream_creation: Whenever the stream is already existing
  • publish_dummy_data: Periodically publish test data to the stream

Replay mode

In this mode the system will replay packets from the stream.

  • deliver_policy: specifies the starting point for the replay
    • all: All messages in the stream
    • last: Last message in the stream
    • new: Deliver only new messages
    • by_start_sequence: { opt_start_seq: <n> }: Starting from sequence number n
    • by_start_time: { opt_start_time: "<t>" }: Starting from time t (RFC3339)
  • replay_policy: specifies how messages will be replayed
    • instant: Sends all messages in the stream to the consumer as quickly as possible
    • original: Sends messages to the stream respecting the rate of arrival
  • bind_address: where to bind the sending socket (default: 0.0.0.0:0)
  • send_address: where to send the received packets
  • sock_broadcast: sets SO_BROADCAST on the socket

Info mode

In this mode the system will show data for a given stream