terraform/vendor/github.com/exponent-io/jsonpath/path.go

68 lines
1.5 KiB
Go

// Extends the Go runtime's json.Decoder enabling navigation of a stream of json tokens.
package jsonpath
import "fmt"
type jsonContext int
const (
none jsonContext = iota
objKey
objValue
arrValue
)
// AnyIndex can be used in a pattern to match any array index.
const AnyIndex = -2
// JsonPath is a slice of strings and/or integers. Each string specifies an JSON object key, and
// each integer specifies an index into a JSON array.
type JsonPath []interface{}
func (p *JsonPath) push(n interface{}) { *p = append(*p, n) }
func (p *JsonPath) pop() { *p = (*p)[:len(*p)-1] }
// increment the index at the top of the stack (must be an array index)
func (p *JsonPath) incTop() { (*p)[len(*p)-1] = (*p)[len(*p)-1].(int) + 1 }
// name the key at the top of the stack (must be an object key)
func (p *JsonPath) nameTop(n string) { (*p)[len(*p)-1] = n }
// infer the context from the item at the top of the stack
func (p *JsonPath) inferContext() jsonContext {
if len(*p) == 0 {
return none
}
t := (*p)[len(*p)-1]
switch t.(type) {
case string:
return objKey
case int:
return arrValue
default:
panic(fmt.Sprintf("Invalid stack type %T", t))
}
}
// Equal tests for equality between two JsonPath types.
func (p *JsonPath) Equal(o JsonPath) bool {
if len(*p) != len(o) {
return false
}
for i, v := range *p {
if v != o[i] {
return false
}
}
return true
}
func (p *JsonPath) HasPrefix(o JsonPath) bool {
for i, v := range o {
if v != (*p)[i] {
return false
}
}
return true
}