为了解决用户输入表达式分析数据的功能，我写了一个Go的JSON表达式分析工具，希望对用Golang的同学有用。

https://github.com/elgs/gojq

gojq

JSON query in Golang.

Install

go get -u github.com/elgs/gojq

This library serves two purposes:

• enables JSON expression evaluation
• reduces the pain of type assertion parsing JSON

Query from JSON Object

package main

import (
    "fmt"
    "github.com/elgs/gojq"
)

var jsonObj = `
{
  "name": "sam",
  "gender": "m",
  "pet": null,
  "skills": [
    "Eating",
    "Sleeping",
    "Crawling"
  ]
}
`

func main() {
    parser, err := gojq.NewStringQuery(jsonObj)
    if err != nil {
        fmt.Println(err)
        return
    }
    fmt.Println(parser.Parse("name"))       // sam <nil>
    fmt.Println(parser.Parse("gender"))     // m <nil>
    fmt.Println(parser.Parse("skills.[1]")) // Sleeping <nil>
    fmt.Println(parser.Parse("hello"))      // <nil> hello does not exist.
    fmt.Println(parser.Parse("pet"))        // <nil> <nil>
}

Query from JSON Array

package main

import (
    "fmt"
    "github.com/elgs/gojq"
)

var jsonArray = `
[
  {
    "name": "elgs",
    "gender": "m",
    "skills": [
      "Golang",
      "Java",
      "C"
    ]
  },
  {
    "name": "enny",
    "gender": "f",
    "skills": [
      "IC",
      "Electric design",
      "Verification"
    ]
  },
  {
    "name": "sam",
    "gender": "m",
    "pet": null,
    "skills": [
      "Eating",
      "Sleeping",
      "Crawling"
    ]
  }
]
`

func main() {
    parser, err := gojq.NewStringQuery(jsonArray)
    if err != nil {
        fmt.Println(err)
        return
    }
    fmt.Println(parser.Parse("[0].name"))       // elgs <nil>
    fmt.Println(parser.Parse("[1].gender"))     // f <nil>
    fmt.Println(parser.Parse("[2].skills.[1]")) // Sleeping <nil>
    fmt.Println(parser.Parse("[2].hello"))      // <nil> hello does not exist.
    fmt.Println(parser.Parse("[2].pet"))        // <nil> <nil>
}

Netsted Query

package main

import (
    "fmt"
    "github.com/elgs/gojq"
)

var jsonArray = `
[
  {
    "name": "elgs",
    "gender": "m",
    "skills": [
      "Golang",
      "Java",
      "C"
    ]
  },
  {
    "name": "enny",
    "gender": "f",
    "skills": [
      "IC",
      "Electric design",
      "Verification"
    ]
  },
  {
    "name": "sam",
    "gender": "m",
    "pet": null,
    "skills": [
      "Eating",
      "Sleeping",
      "Crawling"
    ]
  }
]
`

func main() {
    parser, err := gojq.NewStringQuery(jsonArray)
    if err != nil {
        fmt.Println(err)
        return
    }
    samSkills, err := parser.Parse("[2].skills")
    fmt.Println(samSkills, err) //[Eating Sleeping Crawling] <nil>
    samSkillParser := gojq.NewQuery(samSkills)
    fmt.Println(samSkillParser.Parse("[1]")) //Sleeping <nil>
}