Go的新手，试图弄清楚如何处理JSON

Question

Coming from languages like Python, Ruby, and JS, I am really struggling with Go right now. It feels overly complex, but I am hoping I am just missing something.

Right now I have code that can successfully call Boston's MBTA API (using their public developer key) and return all route information.

I have dropped the code here: http://pastebin.com/PkBaP714 and here: http://pastebin.com/7mRxgrpp

Sample data returned: http://pastebin.com/M2hzMKYs

I want to return two things 1) JUST each route_type and mode_name, and 2) when route_type is called each of the route_id and route_name.

For whatever reason I am just totally lost. I've spent 16 hours staring at documentation and I feel like I am looking at a foreign language :).

It may be too much to ask for specific help, but I would LOVE IT.

Answer 1

Just map them to a new type:

func main() {
    flag.Parse()
    c := gombta.Client{APIKey: apikey, URL: apiurl}

    // get a list of routes by type
    d, err := c.GetRoutes(format)
    check(err)

    var toPrint interface{}

    if typeid == 9999 {
        type Result struct {
            RouteType string `json:"route_type"`
            ModeName  string `json:"mode_name"`
        }
        rs := []Result{}
        for _, m := range d.Mode {
            rs = append(rs, Result{
                RouteType: m.RouteType,
                ModeName:  m.ModeName,
            })
        }
        toPrint = rs
    } else {
        type Result struct {
            RouteID   string `json:"route_id"`
            RouteName string `json:"route_name"`
        }
        rs := []Result{}
        for _, m := range d.Mode {
            if fmt.Sprint(typeid) == m.RouteType {
                for _, r := range m.Route {
                    rs = append(rs, Result{
                        RouteID:   r.RouteID,
                        RouteName: r.RouteName,
                    })
                }
            }
        }
        toPrint = rs
    }

    j, err := json.MarshalIndent(toPrint, "", " ")
    fmt.Printf("RouteTypes: ")
    os.Stdout.Write(j)
}