go-jreader

Safely read specific values from nested JSON objects, maps or slices. Small, zero dependency wrapper interface that allows to use optional chaining in go.

Prerequisites

Requires go1.18 (generics)

Install

go get github.com/fink-al/go-jreader

Usage Examples

// Load JSON data into a JSONElement. Source data may be of type:
//
//  []byte | string | map[string]any | []any |
//  []map[string]any | *[]byte | *string |
//  *map[string]any | *[]any | *[]map[string]any |
//  map[string]string | *map[string]string
//
data, err := jreader.Load("{\"a\": 1}")
data.Get("a").NumberValue() // returns 1, true
data.Get("b").NumberValue() // returns 0, false
data.Get("a").StringValue() // returns "1", true

data, err = jreader.Load([]byte("[{\"a\": 1}]"))
data.Get(0).Get("a").NumberValue() // returns 1, true

data, err = jreader.Load(map[string]any{"a": 1})
data.Get("a").NumberValue() // returns 1, true

data, err = jreader.Load([]any{1, 2, 3})
data.Get(1).NumberValue() // returns 2, true

data, err = jreader.Load([]map[string]any{{"a": 1}, {"b": 2}})
data.Get(1).Get("b").NumberValue() // returns 2, true
data.Get(1).StringValue()          // returns "{\"b\":2}", true

data, err = jreader.Load(createPointer([]byte("{\"nest_lvl1\": {\"nest_lvl2\": 1}}")))
data.Get("nest_lvl1").Get("nest_lvl2").NumberValue() // returns 1, true
data.Get("INVALID").Get("nest_lvl2").NumberValue()   // returns 0, false

jsonObj, _ := jreader.Load("{\"lvl1_nested_obj\": {\"lvl2_nested_list\": [{\"key_of_value\": \"value\"}]}}")
va, ok := jsonObj.Get("lvl1_nested_obj").
  Get("lvl2_nested_list").Get(0).
  Get("key_of_value").StringValue() // returns "value", true

sl, ok := jsonObj.Get("lvl1_nested_obj").
  Get("lvl2_nested_list").SliceValue() // returns []any{{\"key_of_value\": \"value\"}}