README.md

SimpleBinaryEncoding.jl

Zero-copy, zero-allocation serialization and deserialization to/from binary using the Simple-Binary-Encoding format: https://github.com/real-logic/simple-binary-encoding

Message types are described by XML schemas. Running evalschema(MyModule, "myschema.xml") will create wrapper types. These types wrap a buffer of UInt8 and allow one to access and mutate it as if it were an object, or nested objects, following the defintions of the schema.

Current status: basic functionality works but has not been tested outside of the schema formats needed in our application. Variable length data is supported. Static length strings are supported.

If you find any spurious memory allocations, please file an issue.

Examples

Load a schema:

evalschema(Main, "image.xml")

The first argument is the module in which to create the type definitions.

Create a backing byte buffer of at least the size needed for the type:

buf1 = zeros(UInt8, 1000);

Instantiate the wrapper around this buffer:

img = Image(buf1)

The type name is generated from the schema file. No data copying occurs. If the wrapper does not escape, no allocations should occur.

Access properties directly:

img.timestamp = 10

Variable length data is supported if defined in the schema. The buffer size must be large enough, or a bounds error will occur:

resize!(img.frameBuffer, 100*100)
img.frameBuffer .= rand(100*100)

Now let's send the buffer somewhere else. You could write it to a file, send it over the network, etc. Let's try writing to a file and reading it back:

write("tmp.dat", buf)

Note that you could use Aeron.jl or shared memory with Mmap.jl to communicate this data between processes in a truly zero-allocation way.

Let's read it back and interpret it using the same wrapper type:

buf2 = read("tmp.dat")
img2 = Image(buf2)