1# Objx
2[](https://travis-ci.org/stretchr/objx)
3[](https://goreportcard.com/report/github.com/stretchr/objx)
4[](https://codeclimate.com/github/stretchr/objx/maintainability)
5[](https://codeclimate.com/github/stretchr/objx/test_coverage)
6[](https://sourcegraph.com/github.com/stretchr/objx)
7[](https://pkg.go.dev/github.com/stretchr/objx)
8
9Objx - Go package for dealing with maps, slices, JSON and other data.
10
11Get started:
12
13- Install Objx with [one line of code](#installation), or [update it with another](#staying-up-to-date)
14- Check out the API Documentation http://pkg.go.dev/github.com/stretchr/objx
15
16## Overview
17Objx provides the `objx.Map` type, which is a `map[string]interface{}` that exposes a powerful `Get` method (among others) that allows you to easily and quickly get access to data within the map, without having to worry too much about type assertions, missing data, default values etc.
18
19### Pattern
20Objx uses a predictable pattern to make access data from within `map[string]interface{}` easy. Call one of the `objx.` functions to create your `objx.Map` to get going:
21
22 m, err := objx.FromJSON(json)
23
24NOTE: Any methods or functions with the `Must` prefix will panic if something goes wrong, the rest will be optimistic and try to figure things out without panicking.
25
26Use `Get` to access the value you're interested in. You can use dot and array
27notation too:
28
29 m.Get("places[0].latlng")
30
31Once you have sought the `Value` you're interested in, you can use the `Is*` methods to determine its type.
32
33 if m.Get("code").IsStr() { // Your code... }
34
35Or you can just assume the type, and use one of the strong type methods to extract the real value:
36
37 m.Get("code").Int()
38
39If there's no value there (or if it's the wrong type) then a default value will be returned, or you can be explicit about the default value.
40
41 Get("code").Int(-1)
42
43If you're dealing with a slice of data as a value, Objx provides many useful methods for iterating, manipulating and selecting that data. You can find out more by exploring the index below.
44
45### Reading data
46A simple example of how to use Objx:
47
48 // Use MustFromJSON to make an objx.Map from some JSON
49 m := objx.MustFromJSON(`{"name": "Mat", "age": 30}`)
50
51 // Get the details
52 name := m.Get("name").Str()
53 age := m.Get("age").Int()
54
55 // Get their nickname (or use their name if they don't have one)
56 nickname := m.Get("nickname").Str(name)
57
58### Ranging
59Since `objx.Map` is a `map[string]interface{}` you can treat it as such. For example, to `range` the data, do what you would expect:
60
61 m := objx.MustFromJSON(json)
62 for key, value := range m {
63 // Your code...
64 }
65
66## Installation
67To install Objx, use go get:
68
69 go get github.com/stretchr/objx
70
71### Staying up to date
72To update Objx to the latest version, run:
73
74 go get -u github.com/stretchr/objx
75
76### Supported go versions
77We currently support the three recent major Go versions.
78
79## Contributing
80Please feel free to submit issues, fork the repository and send pull requests!
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