udemy-go-web-2/cmd/micro/invoice/helpers.go

87 lines
1.6 KiB
Go

package main
import (
"encoding/json"
"errors"
"io"
"net/http"
"os"
)
type JSONResponse struct {
OK bool `json:"ok"`
Message string `json:"message,omitempty"`
}
func (app *application) readJSON(w http.ResponseWriter, r *http.Request, data interface{}) error {
maxBytes := 1048576
r.Body = http.MaxBytesReader(w, r.Body, int64(maxBytes))
dec := json.NewDecoder(r.Body)
err := dec.Decode(data)
if err != nil {
return err
}
// Make sure there is only one entry.
err = dec.Decode(&struct{}{})
if err != io.EOF {
return errors.New("body must only have a single JSON value")
}
return nil
}
// writeJSON writes arbitrary data out as JSON
func (app *application) writeJSON(
w http.ResponseWriter,
status int, data interface{},
headers ...http.Header,
) error {
out, err := json.MarshalIndent(data, "", "\t")
if err != nil {
return err
}
if len(headers) > 0 {
for k, v := range headers[0] {
w.Header()[k] = v
}
}
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(status)
w.Write(out)
return nil
}
func (app *application) badRequest(w http.ResponseWriter, r *http.Request, err error) error {
var payload JSONResponse
payload.OK = false
payload.Message = err.Error()
out, err := json.MarshalIndent(payload, "", "\t")
if err != nil {
return err
}
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(http.StatusBadGateway)
w.Write(out)
return nil
}
func (app *application) CreateDirIfNotExist(path string) error {
const mode = 0755
if _, err := os.Stat(path); os.IsNotExist(err) {
err := os.Mkdir(path, mode)
if err != nil {
app.errorLog.Println(err)
return err
}
}
return nil
}