README
¶
jsonpointer
golang implementation of IETF RFC6901: JSON Pointer defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document.
Installation
install with:
go get -u github.com/qri-io/jsonpointer
Usage
Here's a quick example pulled from the godoc:
import (
"encoding/json"
"fmt"
"github.com/qri-io/jsonpointer"
)
var document = []byte(`{
"foo": {
"bar": {
"baz": [0,"hello!"]
}
}
}`)
func main() {
parsed := map[string]interface{}{}
// be sure to handle errors in real-world code!
json.Unmarshal(document, &parsed)
// parse a json pointer. Pointers can also be url fragments
// the following are equivelent pointers:
// "/foo/bar/baz/1"
// "#/foo/bar/baz/1"
// "http://example.com/document.json#/foo/bar/baz/1"
ptr, _ := jsonpointer.Parse("/foo/bar/baz/1")
// evaluate the pointer against the document
// evaluation always starts at the root of the document
got, _ := ptr.Eval(parsed)
fmt.Println(got)
// Output: hello!
}
License
MIT
Issues & Contributions
Contributions & Issues are more than welcome! Everything happens over on this repo's github page
Documentation
¶
Overview ¶
Package jsonpointer implements IETF rfc6901 JSON Pointers are a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document [RFC4627]. JSON Pointer is intended to be easily expressed in JSON string values as well as Uniform Resource Identifier (URI) [RFC3986] fragment identifiers.
this package is intended to work like net/url from the go standard library
Example ¶
var document = []byte(`{
"foo": {
"bar": {
"baz": [0,"hello!"]
}
}
}`)
// unmarshal our document into generic go structs
parsed := map[string]interface{}{}
// be sure to handle errors in real-world code!
json.Unmarshal(document, &parsed)
// parse a json pointer. Pointers can also be url fragments
// the following are equivelent pointers:
// "/foo/bar/baz/1"
// "#/foo/bar/baz/1"
// "http://example.com/document.json#/foo/bar/baz/1"
ptr, _ := Parse("/foo/bar/baz/1")
// evaluate the pointer against the document
// evaluation always starts at the root of the document
got, _ := ptr.Eval(parsed)
fmt.Println(got)
Output: hello!
Index ¶
- func WalkJSON(tree interface{}, visit func(elem interface{}) error) error
- type JSONContainer
- type JSONParent
- type Pointer
- func (p Pointer) Descendant(path string) (Pointer, error)
- func (p Pointer) Eval(data interface{}) (result interface{}, err error)
- func (p Pointer) Head() *string
- func (p Pointer) IsEmpty() bool
- func (p Pointer) RawDescendant(path ...string) Pointer
- func (p Pointer) String() (str string)
- func (p Pointer) Tail() Pointer
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
Types ¶
type JSONContainer ¶
type JSONContainer interface {
// JSONProp takes a string reference for a given JSON property.
// implementations must return any matching property of that name,
// nil if no such subproperty exists.
// Note that implementations on slice-types are expected to convert
// prop to an integer value
JSONProp(prop string) interface{}
}
JSONContainer returns any existing child value for a given JSON property string
type JSONParent ¶
type JSONParent interface {
// JSONChildren should return all immidiate children of this element
// with json property names as keys, go types as values
// Note that implementations on slice-types are expected to convert
// integers to string keys
JSONProps() map[string]interface{}
}
JSONParent is an interface that enables tree traversal by listing all immediate children of an object
type Pointer ¶
type Pointer []string
Pointer represents a parsed JSON pointer
func NewPointer ¶ added in v0.1.1
func NewPointer() Pointer
NewPointer creates a Pointer with a pre-allocated block of memory to avoid repeated slice expansions
func Parse ¶
Parse parses str into a Pointer structure. str may be a pointer or a url string. If a url string, Parse will use the URL's fragment component (the bit after the '#' symbol)
func (Pointer) Descendant ¶
Descendant returns a new pointer to a descendant of the current pointer parsing the input path into components
func (Pointer) Eval ¶
Eval evaluates a json pointer against a given root JSON document Evaluation of a JSON Pointer begins with a reference to the root value of a JSON document and completes with a reference to some value within the document. Each reference token in the JSON Pointer is evaluated sequentially.
func (Pointer) IsEmpty ¶ added in v0.1.1
IsEmpty is a utility function to check if the Pointer is empty / nil equivalent
func (Pointer) RawDescendant ¶ added in v0.1.1
RawDescendant extends the pointer with 1 or more path tokens The function itself is unsafe as it doesnt fully parse the input and assumes the user is directly managing the pointer This allows for much faster pointer management
Source Files