Compactr NPM | npm.io

What is this and why does it matter?

Protocol Buffers are awesome. Having schemas to deflate and inflate data while maintaining some kind of validation is a great concept. Compactr's goal is to build on that to better suit the Javascript ecosystem.

    npm install compactr

Implementation

const Compactr = require('compactr');

// Defining a schema
const userSchema = Compactr.schema({ 
	id: { type: 'number' },
	name: { type: 'string' }
});



// Encoding
userSchema.write({ id: 123, name: 'John' });

// Get the header bytes
const header = userSchema.headerBuffer();

// Get the content bytes 
const partial = userSchema.contentBuffer();

// Get the full payload (header + content bytes)
const buffer = userSchema.buffer();




// Decoding a full payload
const content = userSchema.read(buffer);

// Decoding a partial payload (content)
const content = userSchema.readContent(partial);

Size comparison

JSON: {"id":123,"name":"John"}: 24 bytes

Compactr (full): <Buffer 02 00 01 01 04 7b 4a 6f 68 6e>: 10 bytes

Compactr (partial): <Buffer 7b 4a 6f 68 6e>: 5 bytes

Protocol details

Data types

Type	Count bytes	Byte size
boolean	0	1
number	0	8
int8	0	1
int16	0	2
int32	0	4
double	0	8
string	1	2/char
char8	1	1/char
char16	1	2/char
char32	1	4/char
array	1	(x)/entry
object	1	(x)
unsigned	0	8
unsigned8	0	1
unsigned16	0	2
unsigned32	0	4

Count bytes range can be specified per-item in the schema*

See the full Compactr protocol

Benchmarks

[Array] JSON x 737 ops/sec ±1.04% (91 runs sampled)
[Array] Compactr x 536 ops/sec ±1.25% (82 runs sampled)
[Array] size: { json: 0, compactr: 10 }

[Boolean] JSON x 996 ops/sec ±0.84% (93 runs sampled)
[Boolean] Compactr x 1,439 ops/sec ±1.24% (83 runs sampled)
[Boolean] Protobuf x 2,585 ops/sec ±1.32% (91 runs sampled)
[Boolean] size: { json: 23, compactr: 5, protobuf: 5 }

[Float] JSON x 713 ops/sec ±1.29% (88 runs sampled)
[Float] Compactr x 1,056 ops/sec ±1.38% (86 runs sampled)
[Float] Protobuf x 2,432 ops/sec ±1.45% (88 runs sampled)
[Float] size: { json: 41, compactr: 12, protobuf: 12 }

[Integer] JSON x 954 ops/sec ±0.77% (93 runs sampled)
[Integer] Compactr x 1,520 ops/sec ±1.21% (89 runs sampled)
[Integer] Protobuf x 2,676 ops/sec ±1.22% (90 runs sampled)
[Integer] size: { json: 24, compactr: 8, protobuf: 7 }

[Object] JSON x 512 ops/sec ±0.62% (90 runs sampled)
[Object] Compactr x 412 ops/sec ±1.46% (81 runs sampled)
[Object] Protobuf x 898 ops/sec ±0.92% (93 runs sampled)
[Object] size: { json: 46, compactr: 13, protobuf: 25 }

[String] JSON x 432 ops/sec ±0.79% (88 runs sampled)
[String] Compactr x 428 ops/sec ±0.87% (87 runs sampled)
[String] Protobuf x 738 ops/sec ±0.71% (90 runs sampled)
[String] size: { json: 57, compactr: 14, protobuf: 28 }