candid

README

Candid

Exceptions

Nat and Int Types

Since int and uint types are usually 32 bits wide on 32-bit systems and 64 bits wide on 64-bit systems we do not support them in Candid, except passing it to a idl.Nat and idl.Int respectively.

Vector Types

Note that for arrays, you must pass the correct amount of elements.

Variant Types

Variants always expect exactly one label and one value, labels are case-sensitive.

Mapping between Candid and Go Types

IDL Type	Accepted Go Value(s)	Accepted Go Type(s)
null	idl.Null, nil	*
bool	bool	bool
nat	idl.Nat, uint, uint64, uint32, uint16, uint8	idl.Nat
int	idl.Int, int, int64, int32, int16, int8	idl.Int
nat64	uint64, uint32, uint16, uint8	idl.Nat, uint64
nat32	uint32, uint16, uint8	idl.Nat, uint64, uint32
nat16	uint16, uint8	idl.Nat, uint64, uint32, uint16
nat8	uint8	idl.Nat, uint64, uint32, uint16, uint8
int64	int64, int32, int16, int8	idl.Int, int64
int32	int32, int16, int8	idl.Int, int64, int32
int16	int16, int8	idl.Int, int64, int32, int16
int8	int8	idl.Int, int64, int32, int16, int8
float64	float64, float32	float64
float32	float32	float64, float32
text	string	string
reserved	N/A	idl.Reserved
empty	N/A	idl.Empty
principal	principal.Principal, []byte	principal.Principal
opt {x}	nil, {x}	*{x}
vec {x}	nil, []{x}, [i]{x}, []any, [i]{any},	[]{x}, [i]{x}
record ...{x}	struct{ ...{x} }, map[string]any	struct{ ...{x} }, map[string]any
variant ...{x}	struct{ ...{x} }, struct{ ...*{x} }, map[string]any	struct{ ...*{x} }, map[string]any

Documentation

Index

• func DecodeValueString(value []byte) (string, error)
• func DecodeValuesString(types []idl.Type, values []any) (string, error)
• func EncodeValueString(value string) ([]byte, error)
• func ParseDID(raw []byte) (did.Description, error)

Examples

• EncodeValueString
• EncodeValueString (Blob)
• ParseDID

Functions

func DecodeValueString

func DecodeValueString(value []byte) (string, error)

DecodeValueString decodes the given value into a candid string.

func DecodeValuesString

func DecodeValuesString(types []idl.Type, values []any) (string, error)

DecodeValuesString decodes the given values into a candid string.

func EncodeValueString

func EncodeValueString(value string) ([]byte, error)

EncodeValueString encodes the given candid string into a byte slice.

Example

package main

import (
	"fmt"

	"github.com/aviate-labs/agent-go/candid"
)

func main() {
	e, _ := candid.EncodeValueString("0")
	fmt.Printf("%x\n", e)
}

Output:

4449444c00017c00

Example (Blob)

package main

import (
	"fmt"

	"github.com/aviate-labs/agent-go/candid"
)

func main() {
	e, _ := candid.EncodeValueString("(blob \"deadbeef\")")
	fmt.Printf("%x\n", e)
}

Output:

4449444c016d7b0100086465616462656566

func ParseDID

func ParseDID(raw []byte) (did.Description, error)

ParseDID parses the given raw .did files and returns the Program that is defined in it.

Example

package main

import (
	"fmt"
	"os"

	"github.com/aviate-labs/agent-go/candid"
)

func main() {
	raw, _ := os.ReadFile("testdata/counter.did")
	p, _ := candid.ParseDID(raw)
	fmt.Println(p)
}

Output:

service : {
  inc : () -> nat;
}