https://github.com/foxglove/cdr
Common Data Representation serialization and deserialization library
https://github.com/foxglove/cdr
cdr dds deserialization omg-dds ros2 rtps serde serialization typescript
Last synced: 10 months ago
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Common Data Representation serialization and deserialization library
- Host: GitHub
- URL: https://github.com/foxglove/cdr
- Owner: foxglove
- License: mit
- Created: 2021-06-25T22:13:36.000Z (over 4 years ago)
- Default Branch: main
- Last Pushed: 2024-02-29T16:51:13.000Z (almost 2 years ago)
- Last Synced: 2025-04-04T14:02:10.180Z (11 months ago)
- Topics: cdr, dds, deserialization, omg-dds, ros2, rtps, serde, serialization, typescript
- Language: TypeScript
- Homepage:
- Size: 177 KB
- Stars: 13
- Watchers: 3
- Forks: 4
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# @foxglove/cdr
> _Common Data Representation serialization and deserialization library_
[](https://www.npmjs.com/package/@foxglove/cdr)
## Introduction
Common Data Representation (CDR) defines a serialization format for primitive types. When combined with an Interface Definition Language (IDL) it can be used to create complex types that can be serialized to disk, transmitted over the network, etc. while transparently handling endianness and alignment requirements. It's specified by https://www.omg.org/spec/DDSI-RTPS/2.3/PDF (chapter 10) and https://www.omg.org/cgi-bin/doc?formal/02-06-51.
XCDR implementation follows [DDS-XTypes V1.3 specification](https://www.omg.org/spec/DDS-XTypes/1.3/PDF).
CDR is found in OMG DDS (Data Distributed Service) implementations such as the Real-Time Publish Subscribe (RTPS) protocol. This is the wire protocol found in ROS2, and CDR is the default serialization format used in rosbag2.
## Usage
```Typescript
import { CdrReader, CdrSizeCalculator, CdrWriter } from "@foxglove/cdr";
const calc = new CdrSizeCalculator();
calc.int8();
calc.uint8();
calc.int16();
calc.uint16();
calc.int32();
calc.uint32();
calc.int64();
calc.uint64();
calc.float32();
calc.float64();
calc.string("abc".length);
calc.sequenceLength();
console.log(calc.size);
const writer = new CdrWriter();
writer.int8(-1);
writer.uint8(2);
writer.int16(-300);
writer.uint16(400);
writer.int32(-500_000);
writer.uint32(600_000);
writer.int64(-7_000_000_001n);
writer.uint64(8_000_000_003n);
writer.float32(-9.14);
writer.float64(1.7976931348623158e100);
writer.string("abc");
writer.sequenceLength(0);
const reader = new CdrReader(writer.data);
console.log(reader.int8());
console.log(reader.uint8());
console.log(reader.int16());
console.log(reader.uint16());
console.log(reader.int32());
console.log(reader.uint32());
console.log(reader.int64());
console.log(reader.uint64());
console.log(reader.float32());
console.log(reader.float64());
console.log(reader.string());
console.log(reader.sequenceLength());
```
## Alternatives
[jscdr](https://github.com/atolab/jscdr) - Does not support bigint, pre-allocated buffers, or buffer length calculations.
## License
@foxglove/cdr is licensed under the [MIT License](https://opensource.org/licenses/MIT).
## 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
## Stay in touch
Join our [Slack channel](https://foxglove.dev/slack) to ask questions, share feedback, and stay up to date on what our team is working on.