@lichtblick/rosmsg-serialization

ROS1 (Robot Operating System) message serialization, for reading and writing bags and network messages

MessageReader

Message reader deserializes ROS messages into plain objects. The messages are fully deserialized.

import { MessageReader } from "@lichtblick/rosmsg-serialization";

// message definition comes from `parse()` in @lichtblick/rosmsg
const reader = new MessageReader(messageDefinition);

// deserialize a buffer into an object
const message = reader.readMessage([0x00, 0x00, ...]);

// access message fields
message.header.stamp;

LazyMessage

Lazy messages provide on-demand access and deserialization to fields of a serialized ROS message. Creating a lazy message from a buffer performs no de-serialization during creation. Only accessed fields are deserialized; the deserialization occurs at access time.

import { LazyMessageReader } from "@lichtblick/rosmsg-serialization";

// message definition comes from `parse()` in @lichtblick/rosmsg
const reader = new LazyMessageReader(messageDefinition);

// build a new lazy message instance for our serialized message from the Uint8Array
// Note: since deserialization is lazy - avoid-reusing the array you provide for other messages
const message = reader.readMessage([0x00, 0x00, ...]);

// access message fields
message.header.stamp;

MessageWriter

Convert an object, array, or primitive value into binary data using ROS message serialization.

import { MessageWriter } from "@lichtblick/rosmsg-serialization";

// message definition comes from `parse()` in @lichtblick/rosmsg
const writer = new MessageWriter(pointStampedMessageDefinition);

// serialize the passed in object to a Uint8Array as a geometry_msgs/PointStamped message
const uint8Array = writer.writeMessage({
  header: {
    seq: 0,
    stamp: { sec: 0, nsec: 0 },
    frame_id: ""
  },
  x: 1,
  y: 0,
  z: 0
});

Test

yarn test

License

@lichtblick/rosmsg-serialization is licensed under the MIT License.

Releasing

1. Run yarn version --[major|minor|patch] to bump version
2. Run git push && git push --tags to push new tag
3. GitHub Actions will take care of the rest

Benchmarks

The bench folder contains benchmarks. Run with:

yarn bench
yarn bench:benny

To run benchmarks in web:

yarn bench:web