goweb/api/bind.go

85 lines
2.1 KiB
Go

package api
import (
"encoding/json"
"net/http"
"github.com/pkg/errors"
"gitlab.com/wpetit/goweb/logger"
validator "gopkg.in/go-playground/validator.v9"
)
const (
ErrCodeMalformedRequest ErrorCode = "malformed-request"
ErrCodeInvalidRequest ErrorCode = "invalid-request"
ErrCodeInvalidFieldValue ErrorCode = "invalid-field-value"
ErrCodeNotFound ErrorCode = "not-found"
ErrCodeUnknownError ErrorCode = "unknown-error"
ErrCodeUnauthorized ErrorCode = "unauthorized"
ErrCodeForbidden ErrorCode = "forbidden"
)
// Bind parses and bind the request body to the given target
// Bind wil also validates the received data with a validator instance.
// If the data does not match the target constraints, an ErrorResponse will be
// sent back.
// See gopkg.in/go-playground/validator.v9 for more informations about data
// validation.
func Bind(w http.ResponseWriter, r *http.Request, target interface{}) (ok bool) {
if err := parseBody(r, target); err != nil {
logger.Error(r.Context(), "malformed request", logger.E(errors.WithStack(err)))
ErrorResponse(
w, http.StatusBadRequest,
ErrCodeMalformedRequest,
nil,
)
return false
}
validate := validator.New()
if err := validate.Struct(target); err != nil {
handleValidateError(w, err)
return false
}
return true
}
func parseBody(r *http.Request, target interface{}) error {
decoder := json.NewDecoder(r.Body)
if err := decoder.Decode(target); err != nil {
return err
}
return nil
}
type fieldError struct {
Field string
Tag string
Param string
}
func handleValidateError(w http.ResponseWriter, err error) {
if validationErrors, ok := err.(validator.ValidationErrors); ok {
fields := make([]fieldError, 0)
for _, e := range validationErrors {
fields = append(fields, fieldError{
Field: e.Field(),
Tag: e.Tag(),
Param: e.Param(),
})
}
ErrorResponse(
w, http.StatusBadRequest,
ErrCodeInvalidFieldValue,
map[string]interface{}{
"Fields": fields,
},
)
return
}
ErrorResponse(
w, http.StatusBadRequest,
ErrCodeInvalidRequest,
nil,
)
}