用数组解组JSON

Question

I am trying to Unmarshal the following JSON object which is generated by couchDB and returns for a cURL request in Go, the cURL request code is not mentioned here as it is out of scope of this question and I have assigned it to the variable called mail in the code section.

the JSON data structure:

{
"total_rows": 4,
"offset": 0,
"rows": [{
              "id": "36587e5d091a0d49f739c25c0b000c05",
              "key": "36587e5d091a0d49f739c25c0b000c05",
              "value": {
                          "rev": "1-92471472a3de492b8657d3103f5f6e0d"
                       }
        }]
}

and here is my code to unmarshel the above JSON object,

package main

import (
    "fmt"
    "encoding/json"
)

type Couchdb struct {
    TotalRows int `json:"total_rows"`
    Offset    int `json:"offset"`
    Rows      []struct {
        ID    string `json:"id"`
        Key   string `json:"key"`
        Value struct {
             Rev string `json:"rev"`
        } `json:"value"`
    } `json:"rows"`
}

func main() {
     mail := []byte(`{"total_rows":4,"offset":0,"rows":[{"id":"36587e5d091a0d49f739c25c0b000c05","key":"36587e5d091a0d49f739c25c0b000c05","value":{"rev":"1-92471472a3de492b8657d3103f5f6e0d"}}]}`)

     var s Couchdb
     err := json.Unmarshal(mail, &s)
     if err != nil {
         panic(err)
     }


     //fmt.Printf("%v", s.TotalRows)
     fmt.Printf("%v", s.Rows)
}

and the above code is working fine and you can access the working code here with this link in the Go Play Ground.

I need to get the 36587e5d091a0d49f739c25c0b000c05 value which is the id of rows so I am trying to do it like this

fmt.Printf("%v", s.Rows.ID)

and it returns this error prog.go:33:25: s.Rows.ID undefined (type []struct { ID string "json:\"id\""; Key string "json:\"key\""; Value struct { Rev string "json:\"rev\"" } "json:\"value\"" } has no field or method ID)

but it works for fmt.Printf("%v", s.Rows) and it returns

[{36587e5d091a0d49f739c25c0b000c05 36587e5d091a0d49f739c25c0b000c05 {1-92471472a3de492b8657d3103f5f6e0d}}]

My ultimate goal is to get 36587e5d091a0d49f739c25c0b000c05 and assign it to GO variable but stuck getting that value using GO.

Answer 1

You have to call :

fmt.Println(s.Rows[0].ID)