101 lines
2.4 KiB
Go
101 lines
2.4 KiB
Go
// Copyright 2016 Tim Shannon. All rights reserved.
|
|
// Use of this source code is governed by the MIT license
|
|
// that can be found in the LICENSE file.
|
|
|
|
package main
|
|
|
|
import (
|
|
"encoding/json"
|
|
"io"
|
|
"io/ioutil"
|
|
"log"
|
|
"net/http"
|
|
)
|
|
|
|
const (
|
|
statusSuccess = "success"
|
|
statusError = "error"
|
|
statusFail = "fail"
|
|
)
|
|
|
|
const maxJSONSize = 1 << 20 //10MB
|
|
|
|
var errInputTooLarge = &Fail{
|
|
Message: "Input size is too large, please check your input and try again",
|
|
HTTPStatus: http.StatusRequestEntityTooLarge,
|
|
}
|
|
|
|
// JSend is the standard format for a response from townsourced
|
|
type JSend struct {
|
|
Status string `json:"status"`
|
|
Data interface{} `json:"data,omitempty"`
|
|
Message string `json:"message,omitempty"`
|
|
Failures []error `json:"failures,omitempty"`
|
|
More bool `json:"more,omitempty"` // more data exists for this request
|
|
}
|
|
|
|
//respondJsend marshalls the input into a json byte array
|
|
// and writes it to the reponse with appropriate header
|
|
func respondJsend(w http.ResponseWriter, response *JSend) {
|
|
respondJsendCode(w, response, 0)
|
|
}
|
|
|
|
// respondJsendCode is the same as respondJSend, but lets you specify a status code
|
|
func respondJsendCode(w http.ResponseWriter, response *JSend, statusCode int) {
|
|
w.Header().Set("Cache-Control", "no-cache")
|
|
w.Header().Set("Content-Type", "application/json")
|
|
|
|
if len(response.Failures) > 0 && response.Message == "" {
|
|
response.Message = "One or more item has failed. Check the individual failures for details."
|
|
}
|
|
|
|
result, err := json.MarshalIndent(response, "", " ")
|
|
if err != nil {
|
|
log.Printf("Error marshalling response: %s", err)
|
|
|
|
result, _ = json.Marshal(&JSend{
|
|
Status: statusError,
|
|
Message: "An internal error occurred, and we'll look into it.",
|
|
})
|
|
}
|
|
|
|
if statusCode <= 0 {
|
|
switch response.Status {
|
|
case statusFail:
|
|
w.WriteHeader(http.StatusBadRequest)
|
|
case statusError:
|
|
w.WriteHeader(http.StatusInternalServerError)
|
|
}
|
|
//default is status 200
|
|
} else {
|
|
w.WriteHeader(statusCode)
|
|
}
|
|
|
|
_, err = w.Write(result)
|
|
if err != nil {
|
|
log.Printf("Error writing jsend response: %s", err)
|
|
}
|
|
}
|
|
|
|
func parseInput(r *http.Request, result interface{}) error {
|
|
lr := &io.LimitedReader{R: r.Body, N: maxJSONSize + 1}
|
|
buff, err := ioutil.ReadAll(lr)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if lr.N == 0 {
|
|
return errInputTooLarge
|
|
}
|
|
|
|
if len(buff) == 0 {
|
|
return nil
|
|
}
|
|
|
|
err = json.Unmarshal(buff, result)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|