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