path: root/vendor/github.com/uber/jaeger-client-go/utils/http_json.go

// Copyright (c) 2017 Uber Technologies, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package utils

import (
    "encoding/json"
    "fmt"
    "io"
    "io/ioutil"
    "net/http"
)

// GetJSON makes an HTTP call to the specified URL and parses the returned JSON into `out`.
func GetJSON(url string, out interface{}) error {
    resp, err := http.Get(url)
    if err != nil {
        return err
    }
    return ReadJSON(resp, out)
}

// ReadJSON reads JSON from http.Response and parses it into `out`
func ReadJSON(resp *http.Response, out interface{}) error {
    defer resp.Body.Close()

    if resp.StatusCode >= 400 {
        body, err := ioutil.ReadAll(resp.Body)
        if err != nil {
            return err
        }

        return fmt.Errorf("StatusCode: %d, Body: %s", resp.StatusCode, body)
    }

    if out == nil {
        io.Copy(ioutil.Discard, resp.Body)
        return nil
    }

    decoder := json.NewDecoder(resp.Body)
    return decoder.Decode(out)
}