candid

README

Candid Library written in Golang

Candid is an Interface Description Language (IDL). Its primary purpose is to describe the public interface of a canister that runs on the Internet Computer.

This is still entirely experimental.

Contains:

• Parser for the Candid IDL signatures.
• Binary formatting.

Documentation

Index

• func DecodeValue(value []byte) (string, error)
• func DecodeValues(types []idl.Type, values []interface{}) (string, error)
• func EncodeValue(value string) ([]byte, error)
• func HashId(id string) (hash int)
• func ParseDID(raw []byte) (did.Description, error)

Examples

• EncodeValue
• HashId
• ParseDID

Functions

func DecodeValue

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

func DecodeValues

func DecodeValues(types []idl.Type, values []interface{}) (string, error)

func EncodeValue

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

Example

e, _ := candid.EncodeValue("0")
fmt.Printf("%x\n", e)

Output:

4449444c00017c00

func HashId

func HashId(id string) (hash int)

HashId calculates the the hash of the given id.

The hash function is specified as: hash(id) = ( Sum_(i=0..k) utf8(id)[i] * 223^(k-i) ) mod 2^32 where k = |utf8(id)|-1

Example

fmt.Println(HashId("test"))
fmt.Println(HashId("a_very_long_test"))

Output:

1291438162
1731570314

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

raw, _ := ioutil.ReadFile("testdata/counter.did")
p, _ := candid.ParseDID(raw)
fmt.Println(p)

Output:

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