jsonptr

README

jsonptr

An implementation of rfc6901 (json pointer) in Go (golang)

example

Example json

{
	"details":{
		"name":"hello",
		"id":123,
		"num":3.14,
		"flag":true,
		"author":"A Name",
		"nested":{
			"even":"more",
			"id":4,
			"list":["1","2","3"]
	
		},
		"nice":null
	},
	"msg":"hello"
}

Api usage

// get an array entry
num,err := jsonptr.Evaluate(obj, "/details/nested/list/2") // returns string value 3

// get an array entry and parse it
i, err := jsonptr.AsInt(obj,"/details/nested/list/0") // returns int value 1

In case of evaluation errors while resolving the json pointer, you will get nice error messages.

     key 'abc' not found:
        /abc/asd
         ^~~~~~~ available keys: (details|msg)
     key 'asd' not found:
        /details/asd
                 ^~~~ available keys: (author|flag|id|name|nested|nice|num)
     key 'x' not found:
        /details/nested/x
                        ^~ available keys: (even|id|list)
     index out of bounds:
        /details/nested/list/4
                             ^~ index must be in [0...3[
     expected integer index:
        /details/nested/list/a4
                             ^~~ index must be in [0...3[
     key 'a' not found:
        /a/b/c/d
         ^~~~~ object is nil
     key 'x' not found:
        /details/nice/x
                      ^~ object is nil

Documentation

Index

• func Put(objOrArr ObjOrArr, ptr Ptr, value Value) error
• func Unescape(str PtrToken) string
• type Arr
  • func NewArr(slice ...Value) *Arr
  • func (a *Arr) Append(v ...Value) *Arr
  • func (a *Arr) Bool() bool
  • func (a *Arr) Float64() float64
  • func (a *Arr) Get(idx int) Value
  • func (a *Arr) Len() int
  • func (a *Arr) MarshalJSON() ([]byte, error)
  • func (a *Arr) SetAt(idx int, v Value)
  • func (a *Arr) String() string
  • func (a *Arr) UnmarshalJSON(bytes []byte) error
• type Bool
  • func (n Bool) Bool() bool
  • func (n Bool) Float64() float64
  • func (n Bool) String() string
• type Null
  • func (n Null) Bool() bool
  • func (n Null) Float64() float64
  • func (n Null) MarshalJSON() ([]byte, error)
  • func (n Null) String() string
  • func (n Null) UnmarshalJSON(bytes []byte) error
• type Number
  • func (n Number) Bool() bool
  • func (n Number) Float64() float64
  • func (n Number) String() string
• type Obj
  • func NewObj(m map[string]Value) *Obj
  • func (o *Obj) All() iter.Seq2[string, Value]
  • func (o *Obj) Bool() bool
  • func (o *Obj) Float64() float64
  • func (o *Obj) Get(k string) (Value, bool)
  • func (o *Obj) GetOr(k string, defaultValue Value) Value
  • func (o *Obj) Keys() []string
  • func (o *Obj) Len() int
  • func (o *Obj) MarshalJSON() ([]byte, error)
  • func (o *Obj) Put(k string, v Value)
  • func (o *Obj) String() string
  • func (o *Obj) UnmarshalJSON(bytes []byte) error
• type ObjOrArr
• type Primitive
• type Ptr
• type PtrToken
  • func Escape(str string) PtrToken
• type String
  • func (n String) Bool() bool
  • func (n String) Float64() float64
  • func (n String) String() string
• type Value
  • func Eval(objOrArr ObjOrArr, ptr Ptr) (Value, error)
  • func MustEval(objOrArr ObjOrArr, ptr Ptr) Value
  • func ValueOf(from any) Value

Functions

func Put

func Put(objOrArr ObjOrArr, ptr Ptr, value Value) error

Put tries to resolve the given pointer to put the given value. If ptr addresses an array, an index of -1 will just append the value. Otherwise, the array is filled up with nil values. Note that any key which looks like an integer is considered to be an array index and not an object key.

func Unescape

func Unescape(str PtrToken) string

Unescape takes a token and returns the original string. ~0 becomes ~ and ~1 becomes /

Types

type Arr

type Arr struct {
	// contains filtered or unexported fields
}

func NewArr

func NewArr(slice ...Value) *Arr

func (*Arr) Append

func (a *Arr) Append(v ...Value) *Arr

func (*Arr) Bool

func (a *Arr) Bool() bool

func (*Arr) Float64

func (a *Arr) Float64() float64

func (*Arr) Get

func (a *Arr) Get(idx int) Value

func (*Arr) Len

func (a *Arr) Len() int

func (*Arr) MarshalJSON

func (a *Arr) MarshalJSON() ([]byte, error)

func (*Arr) SetAt

func (a *Arr) SetAt(idx int, v Value)

func (*Arr) String

func (a *Arr) String() string

func (*Arr) UnmarshalJSON

func (a *Arr) UnmarshalJSON(bytes []byte) error

type Bool

type Bool bool

func (Bool) Bool

func (n Bool) Bool() bool

func (Bool) Float64

func (n Bool) Float64() float64

func (Bool) String

func (n Bool) String() string

type Null

type Null struct {
}

func (Null) Bool

func (n Null) Bool() bool

func (Null) Float64

func (n Null) Float64() float64

func (Null) MarshalJSON

func (n Null) MarshalJSON() ([]byte, error)

func (Null) String

func (n Null) String() string

func (Null) UnmarshalJSON

func (n Null) UnmarshalJSON(bytes []byte) error

type Number

type Number float64

func (Number) Bool

func (n Number) Bool() bool

func (Number) Float64

func (n Number) Float64() float64

func (Number) String

func (n Number) String() string

type Obj

type Obj struct {
	// contains filtered or unexported fields
}

func NewObj

func NewObj(m map[string]Value) *Obj

func (*Obj) All

func (o *Obj) All() iter.Seq2[string, Value]

func (*Obj) Bool

func (o *Obj) Bool() bool

func (*Obj) Float64

func (o *Obj) Float64() float64

func (*Obj) Get

func (o *Obj) Get(k string) (Value, bool)

func (*Obj) GetOr

func (o *Obj) GetOr(k string, defaultValue Value) Value

func (*Obj) Keys

func (o *Obj) Keys() []string

func (*Obj) Len

func (o *Obj) Len() int

func (*Obj) MarshalJSON

func (o *Obj) MarshalJSON() ([]byte, error)

func (*Obj) Put

func (o *Obj) Put(k string, v Value)

func (*Obj) String

func (o *Obj) String() string

func (*Obj) UnmarshalJSON

func (o *Obj) UnmarshalJSON(bytes []byte) error

type ObjOrArr

type ObjOrArr interface {
	Value
	// contains filtered or unexported methods
}

type Primitive

type Primitive interface {
	// contains filtered or unexported methods
}

type Ptr

type Ptr = string

A Ptr specifies a specific value within a JSON document. See https://tools.ietf.org/html/rfc6901 for the specification.

type PtrToken

type PtrToken = string

A PtrToken is a single element or token of a Ptr

func Escape

func Escape(str string) PtrToken

Escape takes any string and returns a token. ~ becomes ~0 and / becomes ~1

type String

type String string

func (String) Bool

func (n String) Bool() bool

func (String) Float64

func (n String) Float64() float64

func (String) String

func (n String) String() string

type Value

type Value interface {
	String() string
	Bool() bool
	Float64() float64
	// contains filtered or unexported methods
}

func Eval

func Eval(objOrArr ObjOrArr, ptr Ptr) (Value, error)

Eval takes the json pointer and applies it to the given json object or array. Returns an error if the json pointer cannot be resolved.

func MustEval

func MustEval(objOrArr ObjOrArr, ptr Ptr) Value

func ValueOf

func ValueOf(from any) Value

ValueOf deep copies any basic go value type into the according json type. Unsupported values are mapped to Null. Any Value can be marshaled directly to JSON.