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diff --git a/cmd/ponzu/vendor/github.com/tidwall/gjson/README.md b/cmd/ponzu/vendor/github.com/tidwall/gjson/README.md new file mode 100644 index 0000000..bc26c3c --- /dev/null +++ b/cmd/ponzu/vendor/github.com/tidwall/gjson/README.md @@ -0,0 +1,371 @@ +<p align="center"> +<img + src="logo.png" + width="240" height="78" border="0" alt="GJSON"> +<br> +<a href="https://travis-ci.org/tidwall/gjson"><img src="https://img.shields.io/travis/tidwall/gjson.svg?style=flat-square" alt="Build Status"></a><!-- +<a href="http://gocover.io/github.com/tidwall/gjson"><img src="https://img.shields.io/badge/coverage-97%25-brightgreen.svg?style=flat-square" alt="Code Coverage"></a> +--> +<a href="https://godoc.org/github.com/tidwall/gjson"><img src="https://img.shields.io/badge/api-reference-blue.svg?style=flat-square" alt="GoDoc"></a> +</p> + +<p align="center">get a json value quickly</a></p> + +GJSON is a Go package that provides a [very fast](#performance) and simple way to get a value from a json document. The purpose for this library it to give efficient json indexing for the [BuntDB](https://github.com/tidwall/buntdb) project. + +For a command line interface check out [JSONed](https://github.com/tidwall/jsoned). + +Getting Started +=============== + +## Installing + +To start using GJSON, install Go and run `go get`: + +```sh +$ go get -u github.com/tidwall/gjson +``` + +This will retrieve the library. + +## Get a value +Get searches json for the specified path. A path is in dot syntax, such as "name.last" or "age". This function expects that the json is well-formed and validates. Invalid json will not panic, but it may return back unexpected results. When the value is found it's returned immediately. + +```go +package main + +import "github.com/tidwall/gjson" + +const json = `{"name":{"first":"Janet","last":"Prichard"},"age":47}` + +func main() { + value := gjson.Get(json, "name.last") + println(value.String()) +} +``` + +This will print: + +``` +Prichard +``` +*There's also the [GetMany](#get-multiple-values-at-once) function to get multiple values at once, and [GetBytes](#working-with-bytes) for working with JSON byte slices.* + +## Path Syntax + +A path is a series of keys separated by a dot. +A key may contain special wildcard characters '\*' and '?'. +To access an array value use the index as the key. +To get the number of elements in an array or to access a child path, use the '#' character. +The dot and wildcard characters can be escaped with '\'. + +```json +{ + "name": {"first": "Tom", "last": "Anderson"}, + "age":37, + "children": ["Sara","Alex","Jack"], + "fav.movie": "Deer Hunter", + "friends": [ + {"first": "Dale", "last": "Murphy", "age": 44}, + {"first": "Roger", "last": "Craig", "age": 68}, + {"first": "Jane", "last": "Murphy", "age": 47} + ] +} +``` +``` +"name.last" >> "Anderson" +"age" >> 37 +"children" >> ["Sara","Alex","Jack"] +"children.#" >> 3 +"children.1" >> "Alex" +"child*.2" >> "Jack" +"c?ildren.0" >> "Sara" +"fav\.movie" >> "Deer Hunter" +"friends.#.first" >> ["Dale","Roger","Jane"] +"friends.1.last" >> "Craig" +``` + +You can also query an array for the first match by using `#[...]`, or find all matches with `#[...]#`. +Queries support the `==`, `!=`, `<`, `<=`, `>`, `>=` comparison operators and the simple pattern matching `%` operator. + +``` +friends.#[last=="Murphy"].first >> "Dale" +friends.#[last=="Murphy"]#.first >> ["Dale","Jane"] +friends.#[age>45]#.last >> ["Craig","Murphy"] +friends.#[first%"D*"].last >> "Murphy" +``` + +## Result Type + +GJSON supports the json types `string`, `number`, `bool`, and `null`. +Arrays and Objects are returned as their raw json types. + +The `Result` type holds one of these: + +``` +bool, for JSON booleans +float64, for JSON numbers +string, for JSON string literals +nil, for JSON null +``` + +To directly access the value: + +```go +result.Type // can be String, Number, True, False, Null, or JSON +result.Str // holds the string +result.Num // holds the float64 number +result.Raw // holds the raw json +result.Index // index of raw value in original json, zero means index unknown +``` + +There are a variety of handy functions that work on a result: + +```go +result.Value() interface{} +result.Int() int64 +result.Uint() uint64 +result.Float() float64 +result.String() string +result.Bool() bool +result.Array() []gjson.Result +result.Map() map[string]gjson.Result +result.Get(path string) Result +result.ForEach(iterator func(key, value Result) bool) +result.Less(token Result, caseSensitive bool) bool +``` + +The `result.Value()` function returns an `interface{}` which requires type assertion and is one of the following Go types: + + + +The `result.Array()` function returns back an array of values. +If the result represents a non-existent value, then an empty array will be returned. +If the result is not a JSON array, the return value will be an array containing one result. + +```go +boolean >> bool +number >> float64 +string >> string +null >> nil +array >> []interface{} +object >> map[string]interface{} +``` + +## Get nested array values + +Suppose you want all the last names from the following json: + +```json +{ + "programmers": [ + { + "firstName": "Janet", + "lastName": "McLaughlin", + }, { + "firstName": "Elliotte", + "lastName": "Hunter", + }, { + "firstName": "Jason", + "lastName": "Harold", + } + ] +}` +``` + +You would use the path "programmers.#.lastName" like such: + +```go +result := gjson.Get(json, "programmers.#.lastName") +for _,name := range result.Array() { + println(name.String()) +} +``` + +You can also query an object inside an array: + +```go +name := gjson.Get(json, `programmers.#[lastName="Hunter"].firstName`) +println(name.String()) // prints "Elliotte" +``` + +## Iterate through an object or array + +The `ForEach` function allows for quickly iterating through an object or array. +The key and value are passed to the iterator function for objects. +Only the value is passed for arrays. +Returning `false` from an iterator will stop iteration. + +```go +result := gjson.Get(json, "programmers") +result.ForEach(func(key, value gjson.Result) bool{ + println(value.String()) + return true // keep iterating +}) +``` + +## Simple Parse and Get + +There's a `Parse(json)` function that will do a simple parse, and `result.Get(path)` that will search a result. + +For example, all of these will return the same result: + +```go +gjson.Parse(json).Get("name").Get("last") +gjson.Get(json, "name").Get("last") +gjson.Get(json, "name.last") +``` + +## Check for the existence of a value + +Sometimes you just want to know if a value exists. + +```go +value := gjson.Get(json, "name.last") +if !value.Exists() { + println("no last name") +} else { + println(value.String()) +} + +// Or as one step +if gjson.Get(json, "name.last").Exists(){ + println("has a last name") +} +``` + +## Unmarshal to a map + +To unmarshal to a `map[string]interface{}`: + +```go +m, ok := gjson.Parse(json).Value().(map[string]interface{}) +if !ok{ + // not a map +} +``` + +## Working with Bytes + +If your JSON is contained in a `[]byte` slice, there's the [GetBytes](https://godoc.org/github.com/tidwall/gjson#GetBytes) function. This is preferred over `Get(string(data), path)`. + +```go +var json []byte = ... +result := gjson.GetBytes(json, path) +``` + +If you are using the `gjson.GetBytes(json, path)` function and you want to avoid converting `result.Raw` to a `[]byte`, then you can use this pattern: + +```go +var json []byte = ... +result := gjson.GetBytes(json, path) +var raw []byte +if result.Index > 0 { + raw = json[result.Index:result.Index+len(result.Raw)] +} else { + raw = []byte(result.Raw) +} +``` + +This is a best-effort no allocation sub slice of the original json. This method utilizes the `result.Index` field, which is the position of the raw data in the original json. It's possible that the value of `result.Index` equals zero, in which case the `result.Raw` is converted to a `[]byte`. + +## Get multiple values at once + +The `GetMany` function can be used to get multiple values at the same time, and is optimized to scan over a JSON payload once. + +```go +results := gjson.GetMany(json, "name.first", "name.last", "age") +``` + +The return value is a `[]Result`, which will always contain exactly the same number of items as the input paths. + +## Performance + +Benchmarks of GJSON alongside [encoding/json](https://golang.org/pkg/encoding/json/), +[ffjson](https://github.com/pquerna/ffjson), +[EasyJSON](https://github.com/mailru/easyjson), +and [jsonparser](https://github.com/buger/jsonparser) + +``` +BenchmarkGJSONGet-8 15000000 333 ns/op 0 B/op 0 allocs/op +BenchmarkGJSONUnmarshalMap-8 900000 4188 ns/op 1920 B/op 26 allocs/op +BenchmarkJSONUnmarshalMap-8 600000 8908 ns/op 3048 B/op 69 allocs/op +BenchmarkJSONUnmarshalStruct-8 600000 9026 ns/op 1832 B/op 69 allocs/op +BenchmarkJSONDecoder-8 300000 14339 ns/op 4224 B/op 184 allocs/op +BenchmarkFFJSONLexer-8 1500000 3156 ns/op 896 B/op 8 allocs/op +BenchmarkEasyJSONLexer-8 3000000 938 ns/op 613 B/op 6 allocs/op +BenchmarkJSONParserGet-8 3000000 442 ns/op 21 B/op 0 allocs/op +``` + +Benchmarks for the `GetMany` function: + +``` +BenchmarkGJSONGetMany4Paths-8 4000000 319 ns/op 112 B/op 0 allocs/op +BenchmarkGJSONGetMany8Paths-8 8000000 218 ns/op 56 B/op 0 allocs/op +BenchmarkGJSONGetMany16Paths-8 16000000 160 ns/op 56 B/op 0 allocs/op +BenchmarkGJSONGetMany32Paths-8 32000000 130 ns/op 64 B/op 0 allocs/op +BenchmarkGJSONGetMany64Paths-8 64000000 117 ns/op 64 B/op 0 allocs/op +BenchmarkGJSONGetMany128Paths-8 128000000 109 ns/op 64 B/op 0 allocs/op +``` + +JSON document used: + +```json +{ + "widget": { + "debug": "on", + "window": { + "title": "Sample Konfabulator Widget", + "name": "main_window", + "width": 500, + "height": 500 + }, + "image": { + "src": "Images/Sun.png", + "hOffset": 250, + "vOffset": 250, + "alignment": "center" + }, + "text": { + "data": "Click Here", + "size": 36, + "style": "bold", + "vOffset": 100, + "alignment": "center", + "onMouseUp": "sun1.opacity = (sun1.opacity / 100) * 90;" + } + } +} +``` + +Each operation was rotated though one of the following search paths: + +``` +widget.window.name +widget.image.hOffset +widget.text.onMouseUp +``` + +For the `GetMany` benchmarks these paths are used: + +``` +widget.window.name +widget.image.hOffset +widget.text.onMouseUp +widget.window.title +widget.image.alignment +widget.text.style +widget.window.height +widget.image.src +widget.text.data +widget.text.size +``` + +*These benchmarks were run on a MacBook Pro 15" 2.8 GHz Intel Core i7 using Go 1.7.* + +## Contact +Josh Baker [@tidwall](http://twitter.com/tidwall) + +## License + +GJSON source code is available under the MIT [License](/LICENSE). |