Bin

A tiny binary format

This project is licensed under AGPL.

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Encoder

This implements encoding and takes an io.Writer.

Decoder

This implements decoding and takes an io.Reader.

Struct

A map where it can translate into a struct with the help of the tag.

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Usage

Encoder

• Encode - Takes an interface{} and writes to io.Writer, returns an error if value is invalid.
• getType - Takes the type from a reflect.Value, only used for interfaced values.
• structs - Takes a reflect.Value and a boolean if kind is required to write into io.Writer, returns an error if value is either invalid or tag is not a number.

Decoder

• Decode - Takes an interface{} and decodes from io.Reader, returs an error if value is invalid or value is not settable or io.Reader read an invalid VarUint.
• getType - Decodes the type and heads towards decoding it, only used for interfaced values.
• ReadByte - Returns a byte and an io.EOF if io.Read is done.
• structs - Takes a reflect.Value and decodes each struct field, might return an error as the same for Decode.

Struct

• Map - Returns a map representing the struct.
• Get - Returns the key and a status.
• As - Takes an interface{} and sets what the interface{} has, it will do nothing if the interface is not a struct.
• Sub - Takes a tag and an interface{} and sets the interface with the value from the tag.
• maps - Takes a map and ranges through its values returning a readable map.
• fields - Takes a struct and map its fields by their tag, returns map[tag]field
• ranges - Takes fields map and check the values if possible to set, converting if required, if not continue.
• convert - Safe conversion for reflect.Value.
• ptr - Matches the reflect.Value of the field.

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Utilities

This section is used to describe utilities used in the project, some are available, some are not.

General utilities

• Value - Takes an interface{} and returns reflect.Value, if interface is already return it back, else get the absolute value of the interface{}.
• Zero - Initializes a reflect.Value.
• Abs[T] - Gets absolute reflect.Type or reflect.Value.

Marshaling and Unmarshaling utilities

• Marshal - Takes interface{} and returns bytes, returns error as the same as Encoder.
• Unmarshal[T] - Takes []byte and decodes into T, returns error as the same as Decoder.
• UnmarshalAs[T] - Combines Unmarshal[T] and As[T] calls.

interface{} utilities.

• Interface - Takes an interface{} and returns reflect.Value.
• interfaces - Takes a reflect.Value and switches to interface{} whatever is needed, returns itself.
• As[T] - Takes an interface{} and tries to decode into T, if so returns it.
• as2 - Takes a reflect.Type and interface{} being the head behind As[T].
• KeyElem - Takes a reflect.Value expecting arrays, slices and maps and returns its key and element types.

VarInt utilities

• Integer - Integer is an interface with all integer types of Go also allowing other types with integers underlying it.
• VarIntIn[Integer] - Takes int and uint ranges and an io.Writer and returns bytes, error if io.Writer is done.
• VarIntOut[Integer] - Must disclosure the type and takes an io.ByteReader, returns the number and an error if io.Reader of Decoder is done.

Depth utilities

• depth - Takes a reflect.Value kind must be either reflect.Array or reflect.Slice and calculates depth, mixed state and depth sizes.
• fromDepth - Builds a type from depth.
• isMixed ` Check if all arrays are an arrays or slices are all slices, if so returns true.

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Protocol specification

Bin Protocol

Interface Extension

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Example

package main

import (
	"fmt"
	"github.com/Dviih/bin"
	"reflect"
)

type Example struct {
	Twenty  int    `bin:"20"`
	Fifty   []int  `bin:"50"`
	Hundred string `bin:"100"`
}

func main() {
	example := &Example{
		Twenty:  20,
		Fifty:   []int{5, 0},
		Hundred: "A hundred",
	}

	data, err := bin.Marshal(example)
	if err != nil {
		panic(err)
	}

	fmt.Println(data)

	example2, err := bin.Unmarshal[*Example](data)
	if err != nil {
		panic(err)
	}

	fmt.Printf("%+v\n", example2)
	fmt.Println("Equal", reflect.DeepEqual(example, example2))
}

More can be found at bin_test.go, encoder_test.go and decoder_test.go

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Made for Gophers by @Dviih